USAHA 129th Annual Meeting CWD TSE PrP 2025 and a Decade Review

 USAHA 129th Annual Meeting CWD TSE PrP 2025 and a Decade Review

2025 AAVLD/USAHA 129th Annual Meeting CWD TSE PrP October 30, 2025 - November 5, 2025

2025 USAHA 129th Annual Meeting

2025 AAVLD/USAHA Annual Meeting

snip… October 30, 2025 - November 5, 2025

RESOLUTION NUMBER: 21 APPROVED AS AMENDED SOURCE: COMMITTEE ON FARMED CERVIDAE

SUBJECT MATTER: Collection of Research Samples from Cervids Harvested Under Chronic Wasting Disease Herd Plans

RESOLUTION:

The United States Animal Health Association (USAHA) requests that the United States Department of Agriculture (USDA), Animal and Plant Health Inspection Service (APHIS) work with chronic wasting disease (CWD) researchers and state agencies to develop an accessible electronic database that includes a list of current research projects, sample types needed for those projects, and individuals trained to collect those samples.

For tissue and environmental samples collected from farmed cervidae depopulated or harvested under an official herd plan or USDA funded cooperative agreement, the USAHA requests that USDA:

• Urge state agencies to collect research and genetic screening samples from farmed cervids harvested and coordinate with USDA to provide those samples to researchers.

• Provide specific guidance and sampling protocols to state agencies for blood, rectoanal mucosa-associated lymphoid tissue biopsies, lymphoid tissues, deoxyribonucleic acid, and environmental samples.

USAHA further encourages coordination between USDA, state agencies, research institutions, diagnostic laboratories, cervid industry foundations, and outside stakeholders to ensure any collected samples are utilized to advance CWD research, surveillance, and disease management tools with possible funding and resource support.

BACKGROUND INFORMATION:

As part of ongoing efforts to manage and mitigate Chronic Wasting Disease (CWD) in farmed cervid populations, state animal health or wildlife agencies that oversee these populations may require the depopulation or targeted culling of animals under official herd plans. These harvested animals present critical research opportunities to improve CWD diagnostics, genetic susceptibility profiling, and other disease management strategies.2025 USAHA Resolution 21/ page 2 CWD and genetic samples—including blood, rectoanal mucosa-associated lymphoid tissue biopsies, lymphoid tissues, ear punches, and other biological materials—can support ongoing research initiatives that accelerate science-based policy development and enhance long-term disease control outcomes across both wild and farmed cervid populations.

However, many state agencies lack the personnel and capacity to collect and store samples and may be unaware of research initiatives in need of additional materials. The United States Department of Agriculture (USDA) Cervid Health Program works closely with states and CWD researchers and is often informed of planned depopulations as well as current CWD research projects. Cervid industry foundations, such as the Elk Research Foundation and the Cervid Livestock Foundation, provide funding for research that advances knowledge of CWD diagnostics and genetic susceptibility. These foundations may also be aware of individuals trained in sample collection for such research.

A collaborative effort among the USDA, state agencies, cervid industry foundations, and CWD researchers would facilitate the collection of these samples and significantly advance CWD research.

RESOLUTION NUMBER: 22 APPROVED SOURCE: COMMITTEE ON FARMED CERVIDAE

SUBJECT MATTER: Use of Antemortem Testing as a Risk Assessment Tool in Cervid Chronic Wasting Disease Trace-Forward Investigations

RESOLUTION:

The United States Animal Health Association (USAHA) urges state animal health officials and state wildlife officials to consider the appropriate, responsible use of antemortem sampling, such as rectoanal mucosa-associated lymphoid tissue biopsies, as a herd-level risk assessment tool for captive cervids in trace-forward or trace-back herds identified through chronic wasting disease epidemiological investigations. Such sampling should be used to support science-based decision making and may help avoid unnecessary herd depopulations and long-term business interruptions while maintaining animal health safeguards.

Background Information:

When a chronic wasting disease (CWD)-positive animal is identified in a farmed cervid operation, state officials conduct epidemiological investigations. These investigations often result in extended quarantines, depopulation of trace-out animals, or restrictions on herds implicated in these traces—despite having no confirmed positive animals. Such measures can last for multiple years or lead to the depopulation of animals that are ultimately found to be uninfected.

Antemortem testing offers a practical, science-based alternative to herd depopulation or indefinite movement restrictions. Current methods of antemortem sampling do have limitations, including variable sensitivity, a long incubation period for prion detection, and the risk of disease transmission via sampling equipment. However, when used alongside other herd- and animal-specific data—such as genotype, movement history, and herd status— antemortem sampling, including tissue biopsies, can support targeted, risk-based decision- making.

Recent field use by state animal health officials has demonstrated that biopsies of rectoanal mucosa-associated lymphoid tissue (RAMALT) can be an effective tool for identifying infected herds, assessing risk in trace-out herds without confirmed positives, and guiding depopulation and management decisions. Similarly, state wildlife officials have used RAMALT biopsies on elk to assess risk prior to interstate movement for relocation projects.2025 USAHA Resolution 22/ page 2 Importantly, the United States Department of Agriculture’s CWD Program Standard, Part B – Guidance on Response to CWD-Affected Herds, explicitly affirms the authority of state animal health officials to take action based on their own risk assessments. Page 44 states: “Time in quarantine may be lessened for: C. At the discretion of the State representative for a period of time as determined by a risk evaluation based on the findings of the epidemiological investigation.”

This language confirms that states have the discretion to apply, modify, or lift restrictions based on a variety of risk assessment tools, including antemortem diagnostic testing such as RAMALT biopsies. The appropriate and responsible use of these tools can enhance the precision of disease response, reduce unnecessary herd or animal depopulations, and minimize long-term business interruptions—while maintaining essential animal health safeguards.

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USAHA 128th Annual Meeting October 2024 CWD, TSE, Prion Update

https://chronic-wasting-disease.blogspot.com/2025/11/usaha-128th-annual-meeting-october-2024.html

Chronic Wasting Disease Industry/State/Federal Program Standards

September 20, 2022

Introduction

The purpose of these CWD Program Standards is to provide guidance to producers and regulatory officials on how to effectively control CWD and meet the requirements in 9 CFR parts 55 and 81. This document replaces all previous versions of the CWD Program Standards.

The CWD Herd Certification Program (HCP) provides a consistent national approach to certify deer, elk and moose herds as low risk for CWD (9 CFR 55.21-55.25). The interstate movement requirements for deer, elk and moose are designed to mitigate the risk of spreading CWD between states (9 CFR 81). The animal health community has learned much about CWD in the last 50 years. Peer reviewed science indicates the following:

(1) CWD does not affect humans.

(2) CWD does not affect animals other than cervids.

(3) CWD does not devastate wild deer and elk populations in areas where it is endemic.

(4) CWD is now endemic in wild deer and elk populations in 29 states.

(5) CWD will continue to spread in deer and elk populations despite efforts to control the disease. When the CWD control program began, the prevalence of the disease was very low in both farmed and wild deer and elk populations. Strict regulations were implemented to eradicate the disease from farmed deer and elk herds. Since then, CWD has spread rapidly across the United States in both farmed and wild deer and elk populations. Even though CWD is now endemic in at least 29 states, the regulations for farmed deer and elk herds have remained strict. These strict regulations are no longer necessary or appropriate. It is now time to broaden the regulations for control of CWD and make allowance for continuity of business.

We have reached a tipping point in the CWD control program. Considering the ever-increasing prevalence of CWD in wild deer populations, we must now reevaluate our tactics. Depopulation of infected herds should no longer be the cleanup plan of choice, especially in areas of the country where CWD is established in wild cervid populations. Movement of animals from quarantined herds should be allowed under specific conditions. Live-animal tests should be used when possible and innovative testing protocols should be incorporated into case investigations and herd cleanup plans.

Regulations in 9 CFR 55 and 9 CFR 81 were written with enough flexibility to allow all these things to be done. The CFR does not need to be changed. These Program Standards provide further guidance on how to comply with the legal requirements in 9 CFR parts 55 and 81.

Part A of these Program Standards describes the voluntary Herd Certification Program and the requirements for interstate movement of cervids.

Part B of these Program Standards provides guidance on how to respond to the finding of CWD in farmed cervid herds.Definitions

The following definitions and those in 9 CFR 55.1 and 81.1 apply to these CWD Program Standards. Cervid. All members of the family Cervidae and hybrids, including deer, elk, moose, caribou, reindeer, and related species. For the purposes of this document, the term “cervid” refers specifically to cervids naturally (not experimentally) susceptible to CWD. These are animals in the genera Odocoileus, Cervus, and Alces and their hybrids, i.e., deer, elk, and moose.

Commingled. Animals are commingled if they have direct contact with each other, have less than 10 feet of physical separation, or share equipment, pasture, or water sources. Common ownership is not a factor in determining if animals are commingled.

CWD-exposed animal. An animal that is part of a CWD-positive herd, or that has been exposed to a CWD-positive animal or contaminated premises within the previous 5 years.

CWD-exposed herd. A herd in which a CWD-positive animal has resided within 5 years prior to that animal's diagnosis as CWD-positive.

CWD-positive animal. An animal that has had a diagnosis of CWD established through official confirmatory testing conducted by the National Veterinary Services Laboratories.

CWD positive herd. A herd in which a CWD positive animal resided at the time it was diagnosed and which has not been released from quarantine.

CWD-suspect animal. An animal that has tested positive on an unofficial CWD test and the test results have not yet been confirmed at NVSL, or an animal that has clinical signs of CWD.

Certified CWD Sample Collector: An individual who has completed appropriate training and is certified by a State to perform collection, submission, and preservation of samples for CWD testing.

Herd. One or more animals that are (1) under common ownership or supervision and are grouped on one or more parts of any single premises or (2) all animals under common ownership or supervision on two or more premises which are geographically separated but on which animals have been interchanged or had direct or indirect contact with one another.

Herd Inventory: A herd owner’s written or electronic record of all the animals currently in the herd including each animal’s species, date of birth, age, sex, date of acquisition, source and all individual identification numbers. A physical herd inventory is a process where a person physically counts the animals in the herd. A physical herd inventory may include inventory reconciliation where each animal and its identification numbers are examined and compared with current inventory records.

Official CWD test. Any test for the diagnosis of CWD approved by APHIS and conducted in a laboratory approved by APHIS in accordance with 9 CFR 55.8.

Owner: An individual, partnership, company, corporation, or other legal entity that has legal or rightful title to an animal or herd of animals.

Quarantine: An order issued by a State restricting movement of animals from or onto a premises to prevent the spread of disease or pests.

Trace back herd. A herd in which a CWD-positive animal formerly resided.

Trace forward herd. A herd that received exposed animals from a CWD-positive herd within 5 years prior to the diagnosis of CWD or from the identified date of entry of CWD into the positive herd.

2Part A. Voluntary Herd Certification Program (HCP)

1. State Participation

Any state that operates a state program to certify the CWD status of cervid herds may request APHIS to designate the State program as an Approved State CWD Herd Certification Program. APHIS will approve or disapprove a state program in accordance with 9 CFR 55.23(a). An approved state must:

(a) Have the authority to restrict the intrastate movement of all CWD-positive, CWD-suspect, and CWD- exposed animals.

(b) Have the authority to require the prompt reporting of CWD test results and CWD-suspect animals.

(c) Have a signed memorandum of understanding with APHIS that delineates the respective roles of the State and APHIS in CWD Herd Certification Program implementation.

(d) Have placed all known CWD-positive, CWD-exposed, and CWD-suspect animals and herds under movement restrictions and allow movement of animals only under permit.

(e) Conduct trace back investigations of CWD-positive animals and trace forward investigations of CWD- exposed animals and notify other states when appropriate.

(f) Effectively enforce quarantines and laws and regulations for CWD.

(g) Have designated an animal health official to coordinate CWD Herd Certification Program activities.

(h) Have programs to educate those engaged in the interstate movement of cervids regarding requirements for animal identification and recordkeeping.

(i) Require and enforce identification of animals in participating herds.

(j) Maintain a database compatible with the CWD National Database and record information on premises, animals, and herd statuses.

(k) Require CWD tests on all CWD-exposed and CWD-suspect animals that die and require proper disposal of all carcasses.

2. Herd Participation

Any owner of a farmed cervid herd may apply to enroll in the CWD Herd Certification Program by sending a written request to the appropriate state agency. Herd owners must agree to maintain their herds in accordance with the requirements specified in 9 CFR 55.23(b) and allow inspections by regulatory officials to verify that the herd meets these requirements. Herd owners who enroll in the CWD Herd Certification Program agree to maintain their herds in accordance with the following conditions:

(a) Each animal in an enrolled herd must have at least two forms of identification (9 CFR 55.25). One must meet the requirements for official animal identification (9 CFR 55.1). The second must be unique for the individual animal within the herd. The means of identification may include electronic implant, flank tattoo, ear tattoo, tamper-resistant ear tag, or other means approved by APHIS. All animals in an enrolled herd must be identified before reaching 12 months of age or before leaving the herd, whichever occurs first. All animals in the herd, regardless of age, must be identified when a physical inventory is conducted that includes inventory reconciliation.

(b) The herd premises must have perimeter fencing that meets state regulations and is adequate to prevent ingress or egress of cervids.

(c) The owner must immediately report animals that escape or disappear, and all deaths (including 3animals killed on premises maintained for hunting and animals sent to slaughter) of animals in the herd aged 12 months or older. For animals that die, the owner must make the carcasses of the animals available for tissue sampling and testing.

(d) The owner must maintain herd records that include a complete inventory of animals that states the species, age, and sex of each animal, the date of acquisition and source of each animal that was not born into the herd, the date of disposal and destination of any animal removed from the herd, and all individual identification numbers (from tags, tattoos, electronic implants, etc.) associated with each animal.

(e) If an owner wishes to maintain separate herds, there must be a buffer zone of at least 30 feet between the perimeter fencing around each herd and no commingling of animals may occur. Each herd must have its own inventory, working facilities, water sources and equipment.

3. Physical inventory

Upon request from a regulatory official, the owner must allow a regulatory official or a designated accredited veterinarian access to the premises and the herd to conduct a physical inventory. The inventory may consist of a review of herd records with visual examination of an enclosed group of animals or may include inventory reconciliation where each animal and its identification numbers are examined and compared with current inventory records. A physical inventory of a herd will not be requested more frequently than once per year, unless it is determined that a herd is not in compliance with CWD Herd Certification Program requirements. A physical inventory with inventory reconciliation must be performed on each enrolled herd at least once every 36 months.

The owner is responsible for assembling, handling, and restraining the animals and for all costs incurred to present the animals for inspection. When inventory reconciliation is required, the owner must present the entire herd for inspection under conditions where the designated official can safely read all identification on the animals.

4. Herd status

(a) Progression. When a herd is first enrolled in the CWD Herd Certification Program, it will be placed in First Year status. If the herd continues to meet the requirements of the CWD Herd Certification Program, each year, on the anniversary of the enrollment date the herd status will be upgraded by 1 year; i.e., Second Year status, Third Year status, Fourth Year status, and Fifth Year status. One year from the date a herd is placed in Fifth Year status, the herd status will be changed to Certified. The herd will remain in Certified status if it continued to meet the requirements of the program.

(b) Newly formed herds. If a newly formed herd is composed solely of animals obtained from herds already enrolled in the Program, the new herd will have the same program status as the lowest status of any herd that provided animals for the new herd. The enrollment date of the new herd will be the latest enrollment date for any of the source herds.

(c) Addition of animals. Animals may be added from herds with the same or a higher CWD program status with no negative impact on the herd certification status. If animals are added from or commingled with animals from a herd with a lower program status, the herd’s status must be changed to the lower status.

(d) Semen and embryos. Additions of genetic material (germplasm) to a herd will not affect the herd’s CWD status. There is currently no scientific evidence that CWD can be transmitted in germplasm.

(e) Cancellation. The CWD program status of a herd may be cancelled if the owner does not fully comply with program requirements for animal identification, animal testing, and recordkeeping. Following cancellation, the owner may apply to have the herd reinstated to the program at First Year status level with a new enrollment date. The owner of a herd that is cancelled due to noncompliance may apply to enroll a newly formed herd, but any such herd must start at First Year status regardless of the status of the animals from which the herd is composed.

45. CWD testing requirements

Animals in farmed cervid herds that are 12 months of age and over that die or are slaughtered must be tested for CWD with an official CWD test. Tissue samples must be collected by State or APHIS officials, accredited veterinarians, or certified CWD sample collectors. Alternatively, owners may remove and submit the entire head with all attached identification devices to an approved CWD laboratory for tissue collection.

Normal sanitary precautions should be used during sample collection. Gloves should be worn, but use of extensive personal protective equipment (PPE) is not required. Formalin (10 percent neutral buffered formalin) should be handled in a well-ventilated area. If rabies is suspected, samples should not be collected and state regulatory officials should be notified.

6. Missed CWD tests

A “missed test” occurs when a test-eligible animal is lost, dies or is slaughtered and is not successfully tested for CWD. There is no guidance in 9 CFR 55 or 81 on how to handle missed CWD tests. State regulatory officials are to develop state-specific protocols for responding to missed tests. When a missed test occurs, a state representative should conduct a CWD risk assessment of the herd and determine if the herd’s program status will be affected. Risk assessments should take into consideration the status level of the herd, the amount of surveillance testing that has been performed, the length of time the herd has met surveillance requirements, and the number of tests that have been missed.

One missed test should not result in a reduction or suspension of herd status if a herd has certified status and no other CWD tests were missed in the previous 24 months. Otherwise, each missed test should result in a reduction in herd status by one level unless additional animals are tested to supplement CWD surveillance in the herd.

To supplement CWD surveillance in a herd, four (4) additional animals may be tested using live-animal tests to make up for each test that is missed. The four animals to be tested should be of the same sex and species as the untested animal, should have been housed near the untested animal, and should have resided in the herd for approximately the same length of time. Live-animal tests should be allowed for supplemental testing of cervids using rectal biopsy, tonsil biopsy, medial retropharyngeal lymph node biopsy, or other tissue as approved by the state.

Exceptions for missed tests may be made if animals die from anthrax or from another disease where necropsy is contraindicated due to public health risks or if they are lost due to an act of vandalism or natural disaster such as a tornado or flood. An exception may also be granted when multiple animals die during an epidemic disease event. Such exceptions are to be made at the discretion of state regulatory officials.

7. Official CWD tests

(a) Official CWD tests. An official CWD test is one that meets the requirements in 9 CFR 55.8 and includes (1) histopathological examination of central nervous system (CNS) tissues from the animal for characteristic microscopic lesions of CWD using test protocols provided by the National Veterinary Services Laboratories (NVSL), (2) proteinase-resistant protein analysis methods including but not limited to immunohistochemistry (IHC) and/or western blotting on CNS and/or peripheral tissue samples from a live or a dead animal, using test protocols provided by NVSL, or (3) any other test method approved by APHIS.

(b) Postmortem tests. When animals are tested postmortem, collection and submission of both the obex and a medial retropharyngeal lymph node (MRPLN) is recommended. Submission of both tissue samples is not required but it may ensure that a definitive diagnosis can be made. Although submission of both samples is recommended, the value of testing each sample type individually must not be diminished or discounted. At this point in the CWD control program, it is time to use a broader variety of tests and recognize that tests do not have to be perfect to be valuable.

5(c) Live-animal tests. It is time to incorporate and use live-animal tests whenever possible for whole-herd tests, statistical sample tests, and individual animal tests. Live-animal tests currently include the rectal biopsy (rectoanal-associated mucosa-associated lymphoid tissue (RAMALT)), the tonsil biopsy, and the MRPLN biopsy.

(d) Rejection of samples. Samples may be unsuitable for CWD testing if the wrong tissue is submitted, an insufficient amount of tissue is submitted, or the samples are severely autolyzed. If a brain stem sample is submitted and the obex is not visually apparent on histopathology, every attempt should be made to recut the sample to validate the test. When a brain stem sample is submitted and the dorsal motor vagus nucleus cannot be demonstrated on histopathology, a location issue (LOC) should be noted, but test results of should still be reported. When lymph nodes or rectal biopsy samples are submitted that contain fewer than six lymphoid follicles, an insufficient follicle issue (ISF) should be noted, but tests results should still be reported.

It is recommended that a piece of fresh (not in formalin) tissue attached to an official animal identification device be submitted with each sample that is submitted for CWD testing. When removal of a piece of the ear is problematic, a new identification tag may be affixed to the hide skin and submitted with the specimens. This practice allows APHIS to perform DNA comparison testing and genotyping if an animal tests positive for CWD. Failure to submit an identification device is not a reason to reject a sample. (e) Sensitivity and specificity. It is imperative that we know the sensitivity and specificity of each type of CWD test so that regulatory officials and producers can choose the appropriate testing method. The sensitivity and specificity for each type of CWD test is listed in the following table. (Values for sensitivity and specificity are to be added to the table by APHIS and the appropriate research scientists.)

Sensitivity and Specificity of CWD Tests

Test Type Animal Type Sensitivity Specificity Western blot – obex or MRPLN all cervids

IHC – obex all cervids

IHC – MRPLN all cervids

IHC – obex and MRPLN all cervids

IHC – RAMALT biopsy elk

IHC – RAMALT biopsy white-tailed deer

IHC – RAMALT biopsy ELISA (Bio-Rad) – obex white-tailed deer Genotype codon 96 all cervids

ELISA (Bio-Rad) – MRPLN all cervids

8. Interstate movement

(a) Deer, elk, or moose moved interstate must meet the requirements in 9 CFR 81, be accompanied by a certificate of veterinary inspection, and meet the import requirements of the receiving state.

(b) Farmed deer, elk or moose moved interstate must originate from a herd with certified status or move directly to a recognized slaughtering establishment. Federal regulations (9 CFR 81) do not restrict interstate movement of cervids based on the location of the herd of origin. Movement is not restricted from CWD-endemic areas, nor is it restricted based on proximity to CWD cases in farmed or wild cervids. With CWD now endemic in 29 states, state regulators should be encouraged to allow importation of6animals from CWD-certified herds regardless of proximity to CWD cases in farmed or wild deer.

(c) Wild deer, elk, or moose captured in one state for release in another must originate from a source population that is documented to be low risk for CWD based on a CWD surveillance program that is approved by the receiving state and by APHIS.

(d) Notwithstanding any provision in this part, interstate movement of farmed or wild deer, elk, and moose may be allowed under permit on a case-by-case basis when the receiving state and APHIS determine that adequate survey and mitigation procedures are in place to prevent dissemination of CWD. Under this provision, interstate movement of animals that originate from CWD-exposed herds, CWD-positive herds, or herds with less than certified status could be allowed, especially if animals move to destinations where CWD is already endemic.

Part B. Guidance on Responding to Cases of CWD

States that participate in the voluntary CWD herd certification program are required to place all known CWD-positive, CWD-exposed, and CWD-suspect animals and herds under movement restrictions and allow movement of animals from such herds only under permit (9 CFR 55.23). Movement of animals from CWD-positive or CWD-exposed herds is not prohibited. It is only to be restricted as determined by the affected state and allowed only under a state issued permit.

Participating states are required to conduct trace back investigations of CWD-positive animals and trace forward investigations of CWD-exposed animals from CWD-positive herds. They are required to notify other states that may have received trace animals. They are required to have the authority to effectively enforce quarantines.

CWD is now endemic in 29 states and will continue to spread in wild deer and elk populations regardless of how cases of CWD in farmed deer and elk herds are handled. It is time to change the response to cases of CWD in farmed herds. Live-animal tests should be used whenever possible. Movement of animals from herds that are not infected with CWD should not be restricted. New methods to clean up CWD-positive herds other than depopulation should be used. Movement of animals from CWD-positive herds to areas where CWD is already endemic in wild deer should be considered. Deer and elk farmers should not be put out of business unnecessarily. Creative new ways should be developed contol CWD.

1. CWD Case Investigations

CWD case investigations are conducted under state authority. The purpose of a CWD case investigation is to identify CWD-exposed animals and place movement restrictions on them until it is determined if such animals are infected with CWD. During an investigation, the following guidelines should be followed. (a) CWD-positive herd. All animals in a CWD-positive herd are considered CWD-exposed animals. It is imperative that such animals be tested using live-animal tests as quickly as possible to determine their CWD status and remove CWD-positive animals from the herd. Rapid identification of additional CWD- positive animals will also help to identify additional trace back herds.

(b) Trace forward herds. Trace forward herds are those that have received animals from a CWD-positive herd within 5 years prior to the positive diagnosis or from the identified date of entry of CWD into the herd. Animals received from a positive herd are considered CWD-exposed animals. The most probable date of entry of CWD into the positive herd may be less than five years, especially in cases where a CWD certified herd with a good surveillance history becomes infected or the positive animal is less than five years of age. In such cases, only animals that left the positive herd after the probable date of infection should be designated as CWD-exposed animals. It is imperative that such animals be tested using live- animal tests as quickly as possible to determine their CWD status and remove restrictions on the trace forward herd. It is not necessary to euthanize these animals to determine CWD status.

(c) Trace back herds. A trace back herd is one where a CWD-positive animal resided within five years prior to that animal’s positive diagnosis. All animals in a trace back herd are considered CWD-exposed 7animals. It is imperative that such herds be tested using live-animal tests as quickly as possible to determine the CWD status of the herd. It is not necessary to euthanize the animals in these herds to determine CWD status. It is not appropriate to trace animals forward from a trace back herd unless a CWD-positive animal was very recently (within the previous six months) in the herd.

2. Herd plans

A herd plan is not a quarantine. States are required to effectively monitor and enforce quarantines (9 CFR 55.23), but the authority to issue and administer quarantines belongs exclusively to the states.

A herd plan is required under two very specific circumstances. A herd plan is required as part of an agreement to depopulate a herd when federal indemnity is to be paid (9 CFR 55.7). A herd plan is also required to reinstate a herd’s certification status when it is designated as CWD-positive or CWD-exposed (9 CFR 55.22) or when its status is lost or suspended (9 CFR 55.24)

A herd plan is written agreement developed to control the spread of CWD from a CWD-positive herd or to determine the CWD status of a trace back or a trace forward herd. A valid herd plan must be signed by APHIS, a state representative, and the herd owner. A herd plan may include specific requirements for movement of animals, CWD testing animals (using live-animal or postmortem tests), selective culling of animals, or depopulation of the herd.

A herd plan for a CWD-positive herd that is depopulated may also include requirements for (1) placement of animals back on the premises, (2) maintenance of fencing, (3) sharing and moving equipment, and (4) premises cleaning and disinfection.

3. Herd Cleanup

Participating states may consider releasing CWD quarantines by any of the following methods. Live- animal tests should be used in all cases except for depopulation.

(a) Test exposed animals. The quarantine on a trace forward herd must be released immediately if all exposed animals in the herd are tested and CWD is not detected. The quarantine on a trace back herd must be released immediately following a whole-herd test if CWD is not detected.

(b) Test and removal. Whole-herd tests may be conducted on CWD-positive herds every 12 months and CWD-positive animals may be removed from the herd. The quarantine on a CWD-positive herd must be released immediately following two consecutive annual whole-herd tests if no CWD is detected.

(c) Test for 60 months. If all animals 12 months of age or older that die or are slaughtered are tested with an official CWD test for a period of 60 months following the last possible exposure and CWD is not detected, the quarantine must be released

(d) Depopulation. Depopulation of a herd should be used as a last resort. To release a quarantine by depopulation, all cervids in the herd must be euthanized and tested with an official CWD test. Quarantines on CWD-exposed herds must be released immediately following depopulation if no CWD- positive animals are identified. Quarantines on CWD-positive herds must be released 60 months following depopulation and cleaning and disinfection.

(e) Other procedures. Quarantines may be released by other methods approved by state authorities.

5. Carcass disposal

Unless prohibited by state laws, cervid carcasses may be burned, buried, digested by alkaline hydrolysis or disposed of at approved landfills. The prions that cause CWD are not a danger to human health or to animals other than cervids. Prions that cause CWD are like the prions that cause scrapie in sheep and are not a danger to the environment. CWD prions are currently widespread in the environment of at least 29 states. As CWD continues to spread in wildlife populations, the distribution of CWD in the environment will continue to expand.

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AAVLD 69TH / USAHA 130TH ANNUAL MEETING

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USAHA 128th Annual Meeting October 2024 CWD, TSE, Prion Update

PROCEEDINGS ONE HUNDRED AND TWENTY EIGHTH ANNUAL MEETING of the UNITED STATES ANIMAL HEALTH ASSOCIATION

Gaylord Opryland Hotel Nashville, Tennessee

October 10-16, 2024

Presentations and Reports

Cervid Section Summary USDA-APHIS-VS Cervid Health Program Tracy Nichols, USDA-APHIS, Veterinary Services (VS) FY2024 Chronic Wasting Disease (CWD) Detections in Farmed Cervids:

There were 26 new CWD positive farmed cervid herds in FY2024 (20 white-tailed deer, 5 elk, 1 mixed species herds). Sixteen of the herds were not participants in the Federal Herd Certification Program (HCP), three were enrolled, but not certified in the HCP, and seven were certified in the HCP.

158

FARMED CERVIDAE

Fifteen of the 26 newly identified herds were in areas where CWD has been found within 20 miles in wild cervid populations.

CWD Cooperative Agreements:

APHIS-VS funded 30 CWD Cooperative agreements in 2024, and the opportunity for farmed cervids totaled approximately $6 million dollars.

Snip…

Elk Genome Update

Christopher M. Seabury, Texas A&M University

Using an Illumina next-generation sequencing approach, we generated genome sequences for more than 300 farmed elk (Cervus canadensis) distributed across North America; thus, revealing millions of naturally occurring genetic variants. These naturally occurring genetic variants were used to engineer a custom 200,000 genetic marker genotyping array. The array was then used to produce preliminary heritability estimates for differential susceptibility to chronic wasting disease (CWD) in farmed elk from North America, and to conduct a preliminary genome-wide association analysis. Preliminary elk heritability estimates were high, and similar to those published for farmed white-tailed deer, while the initial elk genome-wide association analysis produced overt evidence for polygenic inheritance. Preliminary efforts to assess the accuracy of blinded genomic predictions for CWD status (i.e., postmortem IHC) in farmed elk from CWD positive farms were promising; with similar accuracy to those published for farmed white- tailed deer.

Oklahoma Chronic Wasting Disease (CWD) Genetic Improvement Plan Rod Hall, Oklahoma Department of Agriculture, Food and Forestry During the 2024 legislative session, the Oklahoma legislature passed HB 3462, titled the Chronic Wasting Disease Genetic Improvement Act. This law requires the Oklahoma Department of Wildlife Conservation to test 1,000 native white-tailed deer over the next two years to establish a baseline average of genetic codon markers and genomic breeding values for our native white-tailed herd. Oklahoma Department of Agriculture, Food, and Forestry will develop a program to monitor the genetic codon markers and Genomic Estimated Breeding Value (GEBVs) in participating deer, and to allow deer that have the SS allele at codon 96 and GEBVs at or below - 0.0560 to be released into the wild deer population. Chronic Wasting Disease (CWD) Blood Test Update Gary Pusateri, Dream Genomics, Inc.

An introduction to Dream Genomics and the progress in the use of gene expression technology for the development of a sensitive, early diagnostic for CWD in blood from live deer.

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What Does Science Tell Us About Chronic Wasting Disease (CWD) Incubation in Whitetail Deer?

Christopher M. Seabury, Texas A&M University

With the advent of the USDA Herd Certification Program (HCP) as well as other state CWD surveillance programs that require postmortem IHC testing of all age-eligible deer mortalities for CWD, the real question becomes, how long does it take (post-exposure) to test positive for CWD, and does dose matter? Notably, none of the CWD surveillance programs are geared toward waiting for clinical signs of CWD before initiating any surveillance activities, and some state surveillance programs even require antemortem testing before movement. Nevertheless, using published and unpublished data, we show that white-tailed deer will test positive for CWD (i.e., post exposure with the minimum infective dose) in less than three years, while many will also develop clinical signs requiring euthanasia within that same time period.

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RESOLUTION NUMBER: 21 APPROVED

SOURCE: COMMITTEE ON WILDLIFE

SUBJECT MATTER: CONTROLLED STUDY TO EVALUATE GENETIC INFLUENCE ON CHRONIC WASTING DISEASE IN WHITE-TAILED DEER

BACKGROUND INFORMATION:

Understanding the influence of white-tailed deer genetics on chronic wasting disease (CWD) infection susceptibility and disease progression is an important area of research. Variation in CWD susceptibility of white-tailed deer based on genetics has been documented, but further characterization of variable infection dynamics during controlled studies is needed. Results of such a study are needed for state and federal agencies to make informed decisions when considering policy changes. Further, such information will provide clarity and financial justification for genetic-based herd management decisions. Controlled experiments demonstrate that certain alleles within the prion protein (PrP) gene influence CWD infection and disease (e.g., extending incubation period) and potentially CWD prion strain adaptation/emergence. In addition to the PrP gene, recent studies suggest other genes across the white- tailed deer genome contribute to variation in susceptibility to CWD infection and ongoing efforts utilize Genomic Estimated Breeding Value (GEBV) scores to estimate how susceptible a deer is to infection with CWD. With the goal of lowering CWD risk, development of programs to research and/or implement the use of GEBV for managing farmed white-tailed deer operations is ongoing by state and federal agricultural agencies, universities, and facility owners. In this system, deer with GEBV at or below -0.0560 are promoted as breeding stock, whereas deer with higher GEBV may be recommended for removal.

The use of GEBV scores to manage farmed herds appears to be increasing and state legislation has been passed to create a pathway for the release of farmed deer into the wild with the goal of reducing genetic susceptibility in wild populations. However, the efficacy and implications resulting from this predictive genomic approach to manage farmed herds have not been fully evaluated. Published longitudinal studies on farmed deer operations reveal correlations between GEBV score and CWD status in farmed deer but controlled experimental exposures will provide additional data to more completely evaluate this approach. Such information will provide important additive information for regulatory and animal health agencies considering use of GEBV in CWD prevention and management programs in farmed deer.

Although traditional experimental infection trials may be limited by small numbers of study subjects, such studies are foundationally important in infectious disease research and have greatly enhanced our understanding of

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applied CWD epidemiology and pathobiology that inform current prevention and management programs. Of particular interest are parameters that are readily measurable during controlled CWD exposures, specifically: 1) incubation period, 2) duration, extent, and routes of prion shedding (pre-clinical and clinical), 3) variation in infection outcome (such as prion distribution within lymphoid and nervous tissues), and 4) the influence of GEBV on CWD detection using prion diagnostic assays (antemortem and postmortem).

RESOLUTION:

The United States Animal Health Association requests the United States Department of Agriculture (USDA), Animal and Plant Health Inspection Service, Wildlife Services, National Wildlife Research Center and/or USDA, Agricultural Research Service, Virus and Prion Research Unit, conduct a controlled chronic wasting disease prion experimental exposure of white-tailed deer to compare infection dynamics and outcomes between animals with favorable vs. unfavorable genomic estimated breeding value scores.

*****

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Lessons Learned, Elk Feedgrounds in Wyoming

Samantha Allen, Wyoming Game and Fish Department (WGFD) In 2018, the WGFD’s Commission directed the WGFD to develop a statewide chronic wasting disease (CWD) Plan. During this process it became apparent that the elk feedground system was too complex to tackle and incorporate into the CWD plan. After the CWD plan was approved in 2020, the WGFD Commission directed the Department to develop a new plan/process which would be specific to feedgrounds, called “Elk Feedgrounds: A Challenge We Can Take On”. The process was collaborative in nature, consisting of a steering team of internal Department personnel, and a large-scale public/stakeholder group all facilitated by a third-party. The goal was to consider all biological, social, economic and political issues, along with wildlife diseases, to achieve a durable long-term feedground management plan informed by a public-process for the Department-operated feedgrounds. The Wyoming Elk Feedground Management Plan was approved, in 2024, by the WGFD Commission. For more information on the plan and the process please see:

https://wgfd.wyo.gov/get-involved/public-working-groups/elk-feedgrounds

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CATTLE AND BISON

SUBCOMMITTEE ON CATTLE DISEASE TRACEABILITY

Presentations and Reports

USDA Animal Disease Traceability (ADT) Updates Alex Turner, USDA-APHIS, Veterinary Services (VS)

Dr. Alex Turner opened the presentations by discussing traceability and gave examples of National Western Stock Show (NWSS), the bovine spongiform encephalopathy (BSE) ‘cow that stole Christmas’, U.K. foot-and- mouth disease (FMD) outbreaks, animal disease traceability (ADT) changes that go into effect November 5, 2024…

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• Scrapie Genotyping: https://doi.org/10.1371/journal.pone.0254998

Additional Reports and Info briefs can be found at: https://www.aphis.usda.gov/livestock-poultry-disease/nahms/goat#:~:text=NAHMS%20Goat%20Studies.%20Last%20Modified:%20February%2029,%202024.NAHMS Goat Studies (usda.gov). There are additional publications and reports that will be published soon.

NAHMS studies are generally carried out every 8-10 years. With industry support, the next NAHMS Goat study may occur as early as 2029, with a Needs Assessment in 2027.

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REPORT OF THE COMMITTEE

SUBCOMMITTEE ON SCRAPIE AND IDENTIFICATION

Chair: Keith Forbes, NV

Vice Chair: Cindy Wolf, MN

Heather Damico; Joan Dean Rowe; Rose Digianantonio; Keith Forbes; Larry Forgey; Kaylie Fritts; Garrett Girk; Chelsea Good; Gillian Gwartz; Dan Hadacek; Britney Hagood; Rod Hall; Alex Hamberg; Amy Hendrickson; Janemarie Hennebelle; Heather Hirst; Julie Hurley; Beth Johnson; Jeffrey Kaisand; Diane Kitchen; Kimberly Lehman; Scott Leibsle; Kaitlynn Levine; Rick Linscott; Mary Jane Lis; Jim Logan; Erin Luley; Dave McElhaney; Cheryl Miller; Mike Neault; Cheryl Nelson; Amar Patil; Elisabeth Patton; Olivia Perkins; Patty Scharko; David Schneider; Ryan Scholz; Ben Smith; Gary Stone; Dennis Summers; Diane Sutton; Tyler Thacker; Beth Thompson; Hannah Varnell; Marcus Webster; Cindy Wolf; Ryan Wolker.

The Subcommittee on Scrapie and Identification met during the 2024 Annual Meeting in Nashville, Tennessee on October 13. There were 11 subcommittee members and 36 guests in attendance. At the beginning of the meeting housekeeping issues, mission statement, attendance recording options, and subcommittee member announcements were mentioned. There were no previous resolutions to update, but we did receive one proposed resolution which would be discussed during the business section of the meeting.

Presentations and Reports

National Scrapie Eradication Program Update

Diane Sutton, USDA-APHIS, Veterinary Services (VS)

Over the last two decades, the National Scrapie Eradication Program has been very successful in reducing the prevalence of classical scrapie. No classical scrapie positive animals have been identified since January 2021. Forty-seven states have not had a case of classical scrapie detected in the last seven years. Despite the significant progress in eliminating scrapie, additional classical cases may still exist. The last two cases (2019 and 2021) could not be traced to their herds of origin. These untraceable cases illustrate the need for full compliance with the identification and recordkeeping regulations and for continued surveillance.

The national scrapie surveillance goal is to collect at least 30,000 samples annually, a reduction from 40,000 in previous years. Over the last few years several factors including Covid and the highly pathogenic avian influenza (HPAI) outbreak have impacted our ability to meet this goal. During FY2024 additional efforts were made by APHIS to work with State and industry partners to obtain more samples at slaughter, dealer feedlots, markets, farms, veterinary diagnostic laboratories, and through veterinary referrals which had us on target to meet 30,000 before the emergence of HPAI in dairy cattle reduced sampling. Approximately 25,000 animals were

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sampled for FY2024 and about 80 percent of the states have met or exceeded their sampling minimums.

The United States is now allowing the import of semen and embryos from some scrapie affected countries. To prevent the introduction of scrapie, USDA has established import requirements including an import permit, health certificate from exporting country, receiving flock/herd must have a flock identification (ID) and premises ID or the germplasm storage facility must have a Premises ID recorded in the National Scrapie Database. Post-entry requirements include notification to APHIS confirming receipt and further distribution of the germplasm to flocks only in the National Scrapie Database and official identification of and movement records for all offspring derived from imported germplasm to allow the germplasm and animals derived from it to be located if scrapie is identified in an animal derived from or exposed to the germplasm.

Scrapie Research Update from the Animal Research Unit – Pullman, WA – Assays to Differentiate CWD From Scrapie Prions in Tissues of Small Ruminants

Chungwon Chung, Research, Education, and Economics (REE), Agricultural Research Service (ARS)

Researchers at the Animal Disease Research Unit (ADRU) have made progress in developing assays that can differentiate the presence of chronic wasting disease (CWD) prions from scrapie prions in tissues of sheep and goats. While there are no known cases of natural transmission of CWD from cervid species to small ruminants, limited published data does show that some sheep and a goat could support an infection when CWD was directly injected into the brain. This report will review a dual transgenic mouse bioassay that could differentiate the presence of CWD prions from classical scrapie prions in experimentally infected sheep, and the progress we’ve since made to move from this costly and time-consuming assay to two forms of benchtop assays which can be completed within a week. These benchtop assays detect an essential quality of infectious prions, that is, templated conversion of the normal prion protein to a misfolded form that aggregates. To date, we’ve optimized conditions and reagents used in serial protein cyclic misfolding assay (sPMCA) and in the real-time quaking-induced (RT-QuIC) assay to differentiate CWD prions and classical scrapie prions when present in tissues of the natural hosts. In collaboration with the Canadian Food Inspection Agency (CFIA), these benchtop assays will soon be applied to tissues from sheep and goats experimentally inoculated with CWD from naturally infected elk.

The National Scrapie Eradication Program has Provided Multiple On- Farm Benefits for Sheep and Goat Producers in the U.S. Cindy Wolf, American Association of Small Ruminant Practitioners There have been multiple benefits to producers on farm of the National Scrapie Eradication Program (NSEP). First, the concept and use of individual

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animal identification has been adopted by producers. The initial program devices were visual-based unique individual animal ear tags. Over time USDA APHIS approved additional devices as urged by producers. These include registration tattoos, microchips, Radio Frequency Identification (RFID) eartags and tamper resistant neck collars with attached RFID tags. Commercial and purebred producers alike have been using production records that are only able to be generated because the data that individual animal ID generates. Also, some producers have adopted labor savings technology that combines RFID ear tags, software, and sorting and weighing systems. These systems didn’t exist prior to the NSEP.

The NSEP educated producers regarding genetic-based selection breeding programs that enhance scrapie resistance. The program, some states, regulations, and sheep producers have increased demand for resistant sheep, especially rams. Now producers have expanded their use of genetic selection for other diseases such as ovine progressive pneumonia (OPP).

Lastly there is greater consumer confidence and market access domestically and expanded internationally for breeding stock and germplasm, meat, and dairy and fiber products.

Producers should be proud of their efforts in improving the health of U.S. sheep and goat populations and creating a higher level of sheep and goat traceability than existing prior to the evolution of the current NSEP.

Approaching the Scrapie Finish Line

Amy Hendrickson, American Sheep Industry Association After nearly 80 years, the U.S. is approaching the finish line in its fight to eradicate scrapie from the national sheep flock. A strong partnership between the industry, Animal and Plant Health Inspection Service (APHIS), and the states has been key to this achievement and a strong commitment is needed to finish the fight. It is important to look back at what the industry has endured during that 80-year period to understand why the next three years are the most critical of all.

Until the 1980’s the scrapie control program primarily consisted of laboratory confirmation of clinical scrapie, quarantine and slaughter of all animals in an infected flock, tracing, if possible, and the slaughter of all exposed animals and progeny. The control program didn’t work. Producers still found scrapie in their sheep and the cost when they did was staggering. They, and anyone they worked with, stood to lose their entire flocks when a positive scrapie case was identified. It discouraged reporting.

In the 1980s, some changes to the control program were made. Most notably was the move away from total depopulation. Unfortunately, cases were still missed and by the 1990s it was clear the industry had to make a decision; either continue in what was increasingly felt to be a lost cause or double down and make a true push for eradication of the disease. Bovine spongiform encephalopathy (BSE) in the U.K. played a role in convincing the industry that a serious effort was needed. Having decided to go all in on

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eradication, industry, the states and USDA came together to figuring out how to do it. It was very difficult, but in the end a path forward was forged. In 2001, the Accelerated Scrapie Program was rolled out, and featured three main components:

- Individual animal identification (ID) – not just with affected and associated flocks but all animals upon change of ownership and moving in interstate commerce, with some exceptions.

- Ovine Slaughter Surveillance, and

- Research

The new program worked. The ability to identify cases and to trace animals back to their origin allowed the U.S. to go from 1 in 379 sheep being positive for scrapie to 1 in 50,000 when the last case of scrapie was found in 2021. It cannot be understated the role that research played in this fight. Seedstock producers of breeds that were most susceptible to scrapie changed their flock genetics to develop a natural resistance to scrapie in their sheep. Now, according to USDA, approximately 72% of the US sheep flock is now scrapie resistant.

Producers must be encouraged to remain diligent in the effort to finish the fight. The American Sheep Industry Association (ASI), with help from USDA, has worked to develop materials that remind producers of the importance of the scrapie eradication program. As an example, ASI developed a video on scrapie identification, which was shown to the committee.

It is also important to prepare for the transition to a scrapie-free nation. What will “Scrapie Free” look like in the regulatory scheme of things? Does it mean that the entire program with all its infrastructure is dismantled, with the exception of a minimal surveillance program? Should any components remain intact so that USDA has the ability to manage an unexpected case of scrapie without the nation losing its freedom status? What is needed to do that? These questions and others need to be considered as we look to the future. We cannot wait until the day the US is officially declared scrapie free to have this conversation. ASI, in partnership with the National Institute of Animal Agriculture (NIAA), will host an open meeting in April 2025 to begin those discussions.

To achieve the ultimate goal, the nation must remain vigilant for three more years. It is essential that USDA, the states, and industry continue their commitment to the eradication program. We must not play the role of the hare in the famous Aesop’s fable, The Tortoise and the Hare. Remember, he is so confident that he will win the race that when he sees the finish line he stops to nap, while the Tortoise continues steadily and wins the race. Like the tortoise, we must continue steadfastly to the task at hand and cross this most important finish line.

Committee Business:

A resolution proposal, addressing funding for the National Scrapie Eradication Program to ensure sampling can continue at acceptable levels to

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obtain scrapie-free status, was brought to the floor and a motion was submitted, and seconded, to open discussion regarding the resolution. Discussion ensued and another motion was submitted to amend the proposed resolution which was seconded. Discussion determined the appropriate verbiage to add to the resolution and a motion was seconded to approve the amendment and another motion/second voiced to approve the updated resolution for a vote. A vote was conducted, (quorum present) and a majority approved the amended proposal to advance to the parent Committee on Sheep, Goat and Camelids, and the approved resolution was forwarded to the committee chair for distribution to committee members for review.

No other comments or business remained so the meeting was adjourned.

https://usaha.org/wp-content/uploads/2025/10/2024-Proceedings-of-USAHA_print-9Oct25.pdf

“Dr. Alex Turner opened the presentations by discussing traceability and gave examples of National Western Stock Show (NWSS), the bovine spongiform encephalopathy (BSE) ‘cow that stole Christmas’…” …hold that thought…terry

FARMED CERVIDAE

Presentations and Reports

2022 USAHA Cervid Section Summary USDA-APHIS-VS Cervid Health Program Tracy Nichols, USDA-Animal and Plant Health Inspection Service (APHIS) FY2022 CWD Detections in Farmed Cervids:

There were 23 new chronic wasting disease (CWD) positive farmed cervid herds in FY22 (18 white-tailed deer, 3 elk, 2 mixed species herds).

Fifteen of the herds were not participants in the Federal Herd Certification Program (HCP), two were enrolled, but not certified in the HCP, and six were certified in the HCP. Nineteen of the 23 newly identified herds were in areas where CWD has been found within 20 miles in wild cervid populations.

https://usaha.org/upload/Proceedings/Proceedings_FINAL_2022.pdf

2021 USAHA Cervid Section Summary USDA-APHIS-VS Cervid Health Program

Tracy Nichols, USDA, Animal and Plant Health Inspection Service (APHIS) FY2021 CWD Detections in Farmed Cervids: There were 35 new chronic wasting disease (CWD) positive farmed cervid herds in FY21 (31 white-tailed deer, 1 elk, 3 mixed species herds).

Twenty-three of the herds were not participants in the Federal Herd Certification Program (HCP), four were enrolled, but not certified, in the HCP, and eight were certified in the HCP.

Twenty-one of the 35 newly identified herds were in areas where CWD has been found within 20 miles in wild cervid populations.

https://usaha.org/upload/Committee/2021_USAHA_Proceedings_FINAL_.pdf

Changes in chronic wasting disease ecology in elk at Rocky Mountain National Park

Jenny G. Powers, National Park Service, Biological Resources Division Nathan L. Galloway, National Park Service, Biological Resources Division, Ryan J. Monello, National Park Service, Inventory and Monitoring Program, Pacific Island Network, Margaret A. Wild, Washington State University, Department of Veterinary Microbiology and Pathology

We conducted two key studies at Rocky Mountain National Park, Colorado, to investigate the population-level effects of chronic wasting disease (CWD) in elk with historically high densities (up to 110 elk/km2 on portions of the winter range). CWD was first detected in this population in 1981 and by the early 2000s half of the adult elk found dead tested positive for CWD. We estimated disease prevalence of ~13% (8-19%; n=136) in adult females in 2008. Additionally, we estimated that the population growth rate in female elk was flat (λ~1.0) and that CWD can reduce adult female survival and decrease population growth of elk (Monello et al. Journal of Wildlife Management, 2014). In a subsequent study, we are investigating disease dynamics in the elk population and monitoring changes in disease transmission pressure associated with locally specific reduced elk density and increased elk dispersion. We have a preliminary estimate of prevalence for 2012-2016 of ~8.5% (4.6-13.3%; n=138). Results corroborate that CWD reduces adult female elk survival and this increased mortality decreases the population growth rate. Concurrent with our study, elk are re-distributing to lower elevations outside of the park, where CWD prevalence has always been lower, resulting in much lower densities within the park. The effects of this on CWD prevalence are unclear; movement may simply spatially dilute disease across the landscape or lower densities may reduce disease transmission.

https://usaha.org/upload/Proceedings/2019_Proceedings_FINAL.pdf

“CWD was first detected in this population in 1981 and by the early 2000s half of the adult elk found dead tested positive for CWD.”

https://usaha.org/proceedings/

USAHA 128th Meeting Resolution CWD and Scrapie

The use of GEBV scores to manage farmed herds appears to be increasing and state legislation has been passed to create a pathway for the release of farmed deer into the wild with the goal of reducing genetic susceptibility in wild populations.

https://usaha.org/wp-content/uploads/2024/12/2024-USAHA-Resolutions-21.pdf

If slower disease progression results in longer-lived, infected deer with longer periods of infectiousness, resistance may lead to increased disease transmission rates, higher prion concentrations in the environment, and increased prevalence, as has been observed in some captive deer herds (Miller et al., 2006; Keane et al., 2008a).

http://web.archive.org/web/20121114223603/http://forest.wisc.edu/files/pdfs/samuel/2009%20blanchong%20et%20al%20genetic%20susceptibility%20chronic%20wasting.pdf

***> PROCEEDINGS ONE HUNDRED AND Nineteenth ANNUAL MEETING of the USAHA BSE, CWD, SCRAPIE, PORCINE TSE PRION October 2228, 2015

FY2015 CWD Detections in Farmed Cervids

In FY2015, CWD was identified in eight farmed cervid herds: one whitetailed deer breeding herd in Pennsylvania, one elk breeding herd in Utah (traced back from a hunting facility in Utah), one white-tailed deer (WTD) breeding herd and one WTD hunting preserve in Ohio (owned by the same producer), two WTD breeding herds in Wisconsin, one WTD and elk herd in Texas, and a second WTD herd in Texas (traced from the first positive herd in Texas). The positive animals in Utah, Ohio, and Texas represented the first reported cases of CWD in captive cervids in all three of these States. White-Tailed Deer Breeding Herd, Pennsylvania

On October 6, 2014, the National Veterinary Services Laboratories (NVSL) confirmed CWD in a 6-year-old doe from a captive WTD breeding facility in Reynoldsville, Pennsylvania. The doe was euthanized and tested because she was classified as a CWD-exposed animal that had previously resided in two trace back exposed herds. This herd was assembled in 2013 through the purchase of 16 animals from other HCP-certified herds in Pennsylvania, and had been under quarantine for receiving exposed animals from a trace back exposed herd. The remaining herd of eight WTD was depopulated with Federal indemnity on February 18, 2015, and no additional positive animals were detected. USDA collected samples for research purposes.

Elk Breeding Herd, Utah

On December 23, 2014, NVSL confirmed CWD in 3-year-old captive elk. The elk had been at a hunting park located in northern Utah, where he had resided for approximately 3 weeks prior to being hunter killed. All hunter-killed animals at the hunt park are required to be tested for CWD, and this animal

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was sampled through routine surveillance. The elk was traced back to its herd of origin, and that facility was quarantined. The herd was assembled in 1999 with bulls, and later elk cows, that originated from Colorado. Historical testing records for the herd were unavailable. The remaining 70 elk were depopulated using Federal indemnity funds on March 3, 2015, and an additional 25 elk were confirmed as CWD-positive. USDA collected samples for research purposes. White-Tailed Deer Hunting Preserve, Ohio

On October 22, 2014, NVSL confirmed CWD in a buck taken from a captive WTD deer hunting preserve in Ohio. This was the first time that CWD had been detected in Ohio. The preserve was tested as part of Ohio’s CWD monitoring program. The herd had been under quarantine since April 2014 because it was a trace-forward herd associated with a CWD-exposed herd in Pennsylvania. The positive animal was traced to its herd of origin, a captive WTD breeding herd in Pennsylvania, through DNA identity testing. On November 26, 2014, the Ohio State Veterinarian issued an Order of Destruction for animals on the hunting preserve. The State executed this Order on April 27-30, 2015. The herd of 224 WTD was depopulated and no other positives were detected. USDA did not provide Federal indemnity.

White-Tailed Deer Breeding Herd, Ohio

On March 31, 2015, NVSL confirmed CWD infection in a 5-year-old WTD doe from a captive breeding herd in Holmesville, Ohio. The index animal was received from a Wisconsin WTD farm in January 2013. The CWD-positive herd was owned by the same individual as the Ohio hunt preserve that was found to be CWD positive in October 2014. On May 22, 2015, NVSL confirmed a second positive case in the same herd - a yearling WTD doe that was a natural addition in the same breeding herd. The herd had been under quarantine since April 1, 2014 due to epidemiological linkages with two WTD herds in Pennsylvania – one a positive herd and the other a traceback exposed herd. USDA provided Federal indemnity and depopulated this herd on June 15 and 16, 2015. USDA collected samples for research purposes. NVSL confirmed CWD in 16 additional animals in the herd. Of the 16 positives, one was natural addition and the rest were purchased additions. The positive animals were purchased from February 26, 2013 through September 24, 2013, except for one purchased in 2012. Eleven purchased additions traced-back to three herds in Pennsylvania and four purchased additions traced to three other herds in Ohio.

White-Tailed Deer Breeding Herd, Wisconsin

On October 6, 2014, NVSL confirmed CWD in a 2-year-old doe born in June of 2012 that died on a Richland County farm. The facility is within the CWD management zone in Wisconsin. The remaining 51 deer were euthanized on November 20, 2014, and seven additional positives (all males born in 2012) were found. Two of these seven were purchased additions with the last added to the herd in January 2013. All sales from this herd were to shooting preserves. This premise was double fenced and had been compliant in a herd certification program for over ten years.

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On June 19, 2015, NVSL confirmed CWD in a seven-year-old female WTD from a breeding facility in Eau Claire County. The doe was a natural addition to this breeding herd. This is the first positive CWD case, captive or wild, in this county. The doe was found dead and was showing no clinical signs of CWD at the time of death. Since 2003, this herd has tested 391 animals for CWD and all had “not detected” results. In addition, 317 animals have tested “not detected” from the associated hunting preserve over the same time period. A second positive natural addition doe from this herd was confirmed positive by NVSL on September 10, 2015. Several escape episodes have occurred from this herd. The herd is currently under quarantine and plans are underway for depopulation with State indemnity.

White-Tailed Deer and Elk Breeding Herd, Texas

On June 30, 2015, NVSL confirmed CWD in a 2-year-old WTD buck from a captive WTD and elk breeding herd in Medina County, Texas, approximately 500 miles from previously reported positive free-ranging mule deer in far West Texas. This was the first time that the disease had been detected in farmed cervids in the State. The index buck was born on the premises and found dead on June 18, 2015. Over 40 high-risk deer (i.e., pen mates, dam, others) were euthanized and tested after the index case was found. The NVSL confirmed CWD infection in two of those deer. Interestingly, all three of the positive deer identified to date on this premises have the same AI sire. However, the significance of this finding is unclear. In the past five years, records indicate that 130 WTD from 33 facilities moved into the positive herd and 838 WTD moved out of the positive herd to 147 different herds. One positive WTD was found in one of these trace-out herds (see herd description below). Additionally, 23 elk were also moved from this herd to another herd in TX in 2014. All trace-outs have been intrastate except for movements to two premises in Mexico. Premises that have received deer from the index herd are under movement restrictions. VS is collaborating with animal health authorities in Mexico. VS paid indemnity and depopulated this herd on September 30, 2015, and no additional positive animals were detected. USDA collected samples for research purposes.

White-Tailed Deer Herd, Texas

On September 14, 2015 NVSL confirmed CWD from tissues from a WTD in Lavaca County, Texas. This animal was a traceout from the first CWD positive herd from June 30, 2015. Additional epidemiology is ongoing.

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Chronic Wasting Disease Risk Perception: Why Can’t We All Just Get Along?

Krysten Schuler, Animal Health Diagnostic Center, Cornell University, College of Veterinary Medicine

Additional authors: Alyssa Wetterau, Elizabeth M. Bunting, and Hussni Mohammed

Chronic wasting disease (CWD) is a disease of concern to agencies, sportsmen, and businesses dependent on cervid species. However, disease risk perceptions may vary considerably between groups on wildlife and agriculture sides. We administered an online survey using Qualtrics survey software to the state wildlife agency (n=20), state agriculture agency (n=20), federal (United States Geological Survey (USGS), USDA) and other state agencies (n=9), academics (n=5), sportsmen (n=45), and captive cervid farmers (n=13) between March 2013 and 2014 to gauge attitudes toward potential hazards for CWD transmission to wild white-tailed deer or captive cervids. Of 15 hazards, the high-ranking risks were CWD existing undetected in the wild >1 year, decreased testing without subsidies, high wild deer densities, fence line contact, intrastate movement and importation of captive deer. State wildlife and agriculture officials ranked risks higher than other groups, with captive cervid farmers 50% below the average. Of six identified

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hazard pathways, importation of live cervids and escaped cervids was the highest risk for the wildlife agency (72% probability of CWD introduction), other agency and academic professionals (45%), and sportsmen (43%,) while the agriculture agency was most concerned by wild deer migration with high deer densities (46%). Captive cervid operators were threatened by importation of wild deer parts and then infected carcasses or parts left on the landscape (29%). Professional groups ranked generalized risks similarly, particularly for wild deer, but varied on the most likely disease pathway scenario. These regulating agencies also ranked risks higher than those in the captive cervid industry. Recommendations from this study include reaching agreement that CWD is a problem and strive for prevention and containment. Adequate funding by state and federal agencies for wildlife health programs and stakeholder education, as well as improved wild deer surveillance, would decrease CWD risks. The captive cervid industry could investigate selfregulation or insurance options, in addition to the USDA program. This information could be used to further investigate risk management and communication strategies.

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PROCEEDINGS ONE HUNDRED AND Nineteenth ANNUAL MEETING of the USAHA BSE, CWD, SCRAPIE, PORCINE TSE PRION October 22 28, 2015

https://chronic-wasting-disease.blogspot.com/2016/08/proceedings-one-hundred-and-nineteenth.html

USAHA Report of the Subcommittee on Farmed Cervidae CWD TSE Prion Herds 2015 to 2023

Reports

Report of the Subcommittee on Farmed Cervidae

The Subcommittee on Farmed Cervidae met on October 26, 2015.

http://www.usaha.org/upload/Committee/captive/report-cwal-2015.pdf

REPORT OF THE COMMITTEE ON CAPTIVE WILDLIFE AND ALTERNATIVE LIVESTOCK CWD 2016

http://www.usaha.org/upload/Committee/2016Reports/Captive_Wildlife_Report_2016.pdf

REPORT OF THE COMMITTEE ON CAPTIVE WILDLIFE AND ALTERNATIVE LIVESTOCK CWD 2017

snip...

Update on CWD Ante-mortem Testing-Texas and Wisconsin

Scott Bugai, Private Practitioner

Dr. Bugai’s presentation explained there are four ante-mortem diagnostic tests for transmissible spongiform encephalopathies (TSEs) prion diseases: 1) Nictitating membrane, or “third eyelid,” biopsy; 2) Palatine tonsillar lymphoid tissue biopsy (tonsil biopsy); 3) Rectoanal mucosa-associated lymphoid tissue (RAMALT) biopsy (rectal biopsy) and 4) Medial Retropharyngeal Lymph Node Biopsy.

IHC in tonsillar lymphoid tissue. Sensitivity = 97.3% and Specificity = 100%

Total CWD Testing in Texas Since Finding CWD in 2012:

• TPWD Tests: 36,215 and Other/Private Tests: 82,222= Total Tests: 118,437 (This includes postmortem and live testing).

• Total Live Testing in Texas Since Rule Implementation: TPWD Live Tests: 178 and Other/Private Tests: 24,255= Total Tests: 24,433

Total CWD Positives in Texas: Free Range: 18 and Captive Cervid: 33= Total Positives: 51

• Total CWD Tests Since Finding Disease: Total Tests: 118,437

• Estimated CWD Prevalence: .04%

Cervid Health Update-Status of Updated CWD Standards, TB/Brucellosis Rule

https://www.usaha.org/upload/Committee/2017Reports/Farmed_Cervidae_Report_2017_FINA.docx

REPORT OF THE COMMITTEE ON CAPTIVE WILDLIFE AND ALTERNATIVE LIVESTOCK CWD 2018

https://www.usaha.org/upload/Committee/2018Reports/2018_Farmed_Cervidae_KLJbdr.docx

REPORT OF THE COMMITTEE ON CAPTIVE WILDLIFE AND ALTERNATIVE LIVESTOCK CWD 2019

Cervid Health Update- Status of Updated CWD Standards, TB/Brucellosis Rule, Overview of CWD Nationwide

Dr. Tracy Nichols, USDA-APHIS VS

Dr. Nichols provided an overview of the voluntary Chronic Wasting Disease Herd Certification Program. The revised CWD Standards was published in May 2019 and now in effect. There are 28 states participating in the Chronic Wasting Disease Herd Certification Program, which includes 2,100 enrolled cervid herds with over 1,700 currently certified. 17 new cervid herds were identified with CWD in FY 2019.

https://www.usaha.org/upload/Committee/Farmed%20Cervidae/Farmed_Cervidae_Report_2019.pdf

REPORT OF THE COMMITTEE ON CAPTIVE WILDLIFE AND ALTERNATIVE LIVESTOCK CWD 2020

Presentations and Reports

USDA-APHIS-VS Annual Update from the Cervid Health Team

Tracy Nichols, Animal and Plant Health Inspection Service (APHIS), Veterinary Services (VS)

Fiscal Year (FY) 2020

Voluntary Chronic Wasting Disease Herd Certification Program (HCP)

The APHIS HCP was implemented in 2014. It is a voluntary Federal-State-industry cooperative program administered by APHIS and implemented by participating States. The program provides uniform national herd certification standards that minimize the risk of spreading chronic wasting disease (CWD) in farmed cervid populations. Participating States and herd owners must comply with requirements for animal identification, fencing, recordkeeping, inspections/inventories, as well as animal mortality testing and response to any CWD-exposed, suspect, and positive herds. APHIS monitors the Approved State HCPs to ensure consistency with Federal standards through annual reporting by the States.

The current Cervid Health Program staff officers are as follows: Mark Lyons, Jennifer Siembieda, and Tracy Nichols

Voluntary Herd Certification Participation Summary

 Currently, 28 States participate in the voluntary CWD Herd Certification Program, encompassing 2,145 enrolled herds, of which, 1,723 had the certified status in the program.

 1,616 enrolled deer herds, of which, 1,297 were certified

 371 enrolled elk herds, of which, 328 were certified

 147 enrolled mixed species herds, of which, 98 were certified

CWD in Farmed Cervids

 There were 22 newly identified CWD positive herds in FY20

 13 of these herds were not participants in the Federal HCP

 2 herds were considered enrolled in the HCP

 7 herds were certified in the HCP

 Half of the herds were located within 20 miles of identified CWD in the wild, half were not

CWD Herds by State

Pennsylvania: Eight new CWD positive herds

 Breeding herd of 33 WTD, HCP certified, depopulated with Federal indemnity

 Breeding herd of 6 WTD, not in HCP, depopulated with Federal indemnity

 Breeding herd of 15 WTD, not in HCP, depopulated by owner

 Hunt preserve of 58 WTD, not in HCP, populated and under quarantine

 Breeding herd of 75 WTD, not in HCP, populated and under quarantine

 Breeding herd of WTD, not in HCP, populated and under quarantine

 Breeding herd of 90 WTD, not in HCP, populated and under quarantine

 Breeding herd of 4 WTD, not in HCP, populated and under quarantine

Iowa: Two new CWD positive herds

 Breeding herd of 23 WTD, HCP certified, depopulated with Federal indemnity

 Breeding herd of 13 WTD, HCP certified, depopulated with Federal indemnity

Minnesota: Two new CWD positive herds

 Breeding herd of 3 WTD, enrolled in HCP, not certified, depopulated by owner

 Breeding herd of 6 WTD, enrolled in HCP, not certified, depopulated with Federal indemnity

Colorado: Two new CWD positive herds

 Breeding herd/hunt preserve of 9 elk, HCP certified, depopulated by owner

 Breeding herd of 8 elk, HCP certified, populated and under quarantine

Utah: Two new CWD positive herds

 Breeding herd of 465 elk, not in HCP, partial depopulation with Federal indemnity removed purchased animals, populated-quarantine

 Breeding herd of 103 elk, not in HCP, partial depopulation with Federal indemnity removed purchased animals, populated-quarantine

Michigan: One new CWD positive herd

 Hunt preserve of >600 WTD, not in HCP, populated and under quarantine

Montana: One new CWD positive herd

 Breeding herd of 3 elk, not in HCP, populated and under quarantine

Texas: one new CWD positive herd

 Breeding herd of 59 WTD, not in HCP, depopulated with Federal indemnity

Kansas: One new CWD positive herd

 Breeding herd of 20 elk, HCP certified, depopulated with Federal indemnity

Ohio: Eight new CWD positive herd

 Breeding herd of 138 WTD, HCP certified, depopulated with Federal indemnity

Research

 Whole genome study investigating the association of genetics with CWD susceptibility has been published.

 Blinded validation of the genetic predicative model is almost complete.

 A standardized protocol has been developed, in partnership with Agricultural Research Service (ARS), United States Geological Survey (USGS), University of Wisconsin, and National Institutes of Health (NIH) for tissue sample testing using real-time quaking-induced conversion (RT-QuIC).

 A study is starting shortly to determine the sensitivity and specify of RT-QuIC utilizing the standardized protocol.

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https://www.usaha.org/upload/Committee/2020Reports/Farmed_Cervidae_Report_2020.pdf

REPORT OF THE COMMITTEE ON CAPTIVE WILDLIFE AND ALTERNATIVE LIVESTOCK CWD 2021

Presentations and Reports

2021 USAHA Cervid Section Summary USDA-APHIS-VS Cervid Health Program

Tracy Nichols, USDA, Animal and Plant Health Inspection Service (APHIS)

FY2021 CWD Detections in Farmed Cervids: There were 35 new chronic wasting disease (CWD) positive farmed cervid herds in FY21 (31 white-tailed deer, 1 elk, 3 mixed species herds). Twenty-three of the herds were not participants in the Federal Herd Certification Program (HCP), four were enrolled, but not certified, in the HCP, and eight were certified in the HCP. Twenty-one of the 35 newly identified herds were in areas where CWD has been found within 20 miles in wild cervid populations.

***> While resistant alleles have been identified in cervids, a PRNP variant that completely prevents CWD has not yet been identified.

Thus, control of the disease in farmed herds traditionally relies on quarantine and depopulation.

https://www.usaha.org/upload/Committee/2021Reports/2021_Farmed_Cervidae.docx

REPORT OF THE COMMITTEE ON CAPTIVE WILDLIFE AND ALTERNATIVE LIVESTOCK CWD 2022

Three presentations were given during the October 10, 2022 meeting. The following presentation summaries were given starting in order at number one:

1. Dr. Tracy Nichols, PhD, USDA /APHIS Fort Collins, CO

2022 USAHA Cervid Section Summary USDA APHIS VS Cervid Health Program

FY2022 CWD Detections in Farmed Cervids: There were 23 new CWD positive farmed cervid herds in FY 22 (18 white-tailed deer, 3 elk, 2 mixed species herds). Fifteen of the herds were not participants in the Federal Herd Certification Program (HCP), two were enrolled, but not certified, in the HCP, and six were certified in the HCP. Nineteen of the 23 newly identified herds were in areas where CWD has been found within 20 miles in wild cervid populations.

https://www.usaha.org/upload/Committee/2022Reports/2022_Farmed_Cervidae.docx

https://www.usaha.org/farmed-cervidae

''Dr. Anderson presented a draft rewrite of the CWD Program Standards that supports the requirements specified in 9 CFR 55 and 81 and outlines a program to control CWD in farmed cervid herds without causing unnecessary harm to cervid producers.''

SUNDAY, JANUARY 12, 2020 2019

USAHA-AAVLD Annual Meeting October 24-30, 2019 Transmissible Spongiform Encephalopathy TSE Prion CWD, Scrapie UPDATE

https://chronic-wasting-disease.blogspot.com/2020/01/2019-usaha-aavld-annual-meeting-october.html

TUESDAY, MARCH 26, 2019

USDA ARS 2018 USAHA RESOLUTIONS Investigation of the Role of the Prion Protein Gene in CWD Resistance and Transmission of Disease

https://chronic-wasting-disease.blogspot.com/2019/03/usda-ars-2018-usaha-resolutions.html

RESOLUTION NUMBER: 16, 23, and 40 Combined APPROVED

SOURCE: COMMITTEE ON SCRAPIE

COMMITTEE ON LIVESTOCK IDENTIFICATION

COMMITTEE ON SHEEP AND GOATS

SUBJECT MATTER: Continued United States Department of Agriculture Provision of Plastic Scrapie Program Ear Tags for Sheep and Goats Producers

BACKGROUND INFORMATION:

While the National Scrapie Eradication Program (NSEP) has succeeded in decreasing the prevalence of scrapie in the United States, the NSEP has not eradicated scrapie in sheep or goats. The NSEP must make continued improvements in traceability and surveillance is needed, not just to achieve the eradication of scrapie, but also to advance animal disease traceability (ADT) efforts.

Much of the success of the NSEP is attributable to the U.S. Department of Agriculture (USDA), Animal and Plant Health Inspection Service’s work with producers to find identification (ID) devices with good retention and that lend themselves to improving animal care and management. Currently, USDA provides small metal tags or more visible plastic ear tags to producers, sales yards, fairs, veterinarians, and veterinary clinics. The plastic tags have a larger profile and lend themselves to management systems where tag numbers are read and recorded. The metal tags are too small to be used as visible ID for management purposes, and they are more likely to lead to infections in goats than the plastic tags.

The publication of the NSEP final rule is expected in 2017 and will include new requirements for official identification and traceability for certain classes of goats and sheep previously excluded from mandatory official ID. In addition to the increasing numbers of new sheep and goat producers entering the program on a continuing basis, longtime producers of low-risk goats and sheep, who were previously exempted, will have mandatory ID requirements for the first time. A change in tag-provision policy at this critical time jeopardizes the ability of veterinarians and scrapie program officials to facilitate compliance by these herd owners. Elimination of USDA-provided tags that provide visible ID will compromise accurate recording of ID and compliance with recordkeeping requirements for both traceability and the scrapie program.

10

USAHA/2016

Resolution 16, 23, 40

USDA should explore alternative sources of funds and cost saving options to support the USDA provided plastic ear tags. Benefits of the USDA-provided plastic tags outweigh the savings that could be achieved by cutting the funding for this item. The success in ADT attributable to the NSEP and the wide adoption of sheep and goat plastic ear tags demonstrate the value of providing ID options that benefit both producers and traceability.

RESOLUTION:

The U.S. Animal Health Association urges the U.S. Department of Agriculture (USDA), Animal and Plant Health Inspection Service to continue to provide plastic ear tags for the National Scrapie Eradication Program (NSEP) in the most economical and case appropriate manner. These USDAprovided tags are critical to successful identification and traceability of sheep and goats for NSEP and animal disease traceability.

FINAL RESPONSE:

The U.S. Department of Agriculture, Animal and Plant Health Inspection Service (APHIS), Veterinary Services recognizes the concerns of the U.S. Animal Health Association and appreciates the opportunity to respond. APHIS does not expect to receive an increase in funding in the Equine, Cervid, and Small Ruminant line item in fiscal year (FY) 2018. Further, we have exhausted the no-year funding that was used to provide official eartags to producers in recent years. As a result, APHIS is looking at ways to reduce tag costs to preserve other scrapie program activities under our expected FY 2018 budget. APHIS is considering several options that may be implemented alone or in combination, including providing only metal eartags, providing a limited number of plastic tags to any one entity, not providing tag applicators, and/or changing the way metal tags are distributed. APHIS recognizes that reducing or eliminating the availability of USDAprovided official plastic tags may adversely impact ID compliance and thereby traceability; however, other options for cutting costs, such as reducing scrapie surveillance, would likely have greater negative impacts on the program. APHIS has not made a final decision at this time.

11

RESOLUTION NUMBER: 17 and 41 Combined APPROVED

SOURCE: COMMITTEE ON SCRAPIE

COMMITTEE ON SHEEP AND GOATS

SUBJECT MATTER: Goat Scrapie Genetic Resistance

BACKGROUND INFORMATION:

Genotype selection for scrapie resistance in sheep has proven to be a great asset in efforts to eradicate scrapie in sheep. The availability of genetic tools for goats should have similar benefits. Based on the information presented by the U.S. Department of Agriculture, Agricultural Research Service researchers, sufficient data exists to support further efforts toward testing for goat scrapie genotype resistance and development of field applications in the National Scrapie Eradication Program.

RESOLUTION:

The U.S. Animal Health Association (USAHA) urges the U.S. Department of Agriculture (USDA), Animal and Plant Health Inspection Service to pursue efforts to develop pilot projects to explore the use of goat scrapie genotype testing in the National Scrapie Eradication Program. USAHA also requests that USDA-Agricultural Research Service conduct surveys to assess the frequency of resistant genotypes in U.S. goats and identify methods to expand the availability of resistant genotypes to U.S. goat producers.

FINAL RESPONSE:

The U.S. Department of Agriculture, Animal and Plant Health Inspection Service (APHIS), Veterinary Services recognizes the concerns of the U.S. Animal Health Association and appreciates the opportunity to respond. We understand the importance of better characterization of genetic resistance to scrapie in goats to assist producers in breeding for resistance and to reduce the number of animals depopulated in a herd when scrapie is detected. However, genetic resistance to scrapie is more difficult to characterize in goats compared to sheep because of a wider number and variety of genotypes associated with resistance and fewer cases of scrapie in goats in the United States, resulting in less research. APHIS continues to prioritize the importance of this research with our partners at the Agricultural Research Service (ARS) and will develop genetic-based flock plans for scrapie infected goatherds, as appropriate.

***In July 2017, APHIS provided ARS with 43 scrapie exposed goats when an infected herd was depopulated

12

RESOLUTION NUMBER: 18 APPROVED

SOURCE: COMMITTEE ON SCRAPIE

SUBJECT MATTER: Identifying Non-Traditional Sheep and Goat Marketing and Slaughter Channels

BACKGROUND INFORMATION:

While the National Scrapie Eradication Program (NSEP) has been successful in decreasing the prevalence of scrapie in the United States, the NSEP has not yet achieved eradication of the disease. With all disease eradication programs, as prevalence of the disease declines, the ability to identify the remaining cases becomes an ever greater challenge.

There is evidence that increasing numbers of sheep and goats are marketed and slaughtered outside of the traditional marketing system and may not be available for scrapie surveillance, the impact of which may prolong the time until eradication is achieved. It is also likely that the demand for nontraditionally marketed animals will continue to rise, resulting in negative ramifications for the program.

RESOLUTION:

The U.S. Animal Health Association urges the U.S. Department of Agriculture, Animal and Plant Health Inspection Service, Veterinary Services to actively pursue identification of nontraditional sheep and goat marketing and slaughter channels and to create a program to obtain samples from these channels.

FINAL RESPONSE:

The U.S. Department of Agriculture, Animal and Plant Health Inspection Service, Veterinary Services (VS) recognizes the concerns of the U.S. Animal Health Association and appreciates the opportunity to respond. VS agrees with the importance of identifying nontraditional sheep and goat marketing and slaughter channels to improve the coverage of scrapie surveillance across all segments of the sheep and goat populations. VS has provided support to collect and test samples from sheep and goats offered for sale at live-bird markets in Texas and New York. VS will continue to encourage efforts to identify and collect and test samples from nontraditional outlets for selling and slaughtering sheep and goats, as funding is available.

http://www.usaha.org/upload/Resolution/2016/APHIS_VS_2017_Final_Resolutions_.pdf

FRIDAY, OCTOBER 20, 2017

USAHA Live Animal Testing for Chronic Wasting Disease CWD TSE Prion

http://chronic-wasting-disease.blogspot.com/2017/10/usaha-live-animal-testing-for-chronic.html

RESOLUTION NUMBER: 30 APPROVED

SOURCE: COMMITTEE ON CAPTIVE WILDLIFE AND ALTERNATIVE LIVESTOCK

SUBJECT MATTER: Live Animal Testing for Chronic Wasting Disease

BACKGROUND INFORMATION: Detection of Chronic Wasting Disease (CWD) in live animals is an important component of CWD Prevention and Control Programs.

With the funding decrease for CWD indemnification, the need for a successful live animal test option, with a high rate of sensitivity and specificity, is critical in both a trace-forward / trace-back scenario, as well as in herd management plans.

There have been numerous studies evaluating the sensitivity and specificity of tonsillar biopsies in cervids. Similar to scrapie, PrP(CWD) in deer accumulates in the retropharyngeal lymph nodes and tonsillar follicles before central nervous system involvement or clinical symptoms (Sigurdson et al., 1999; Spraker et al., 2002b; O’Rourke et al., 2003). Antemortem testing of these tissues by immunohistochemistry provides a reliable preclinical diagnosis in deer (Wild et al., 2002; Wolfe et al., 2002).

RESOLUTION: The United States Animal Health Association urges the United States Department of Agriculture, Animal and Plant Health Inspection Service, Veterinary Services to expedite evaluation and approval of tonsillar biopsies into the Chronic Wasting Disease (CWD) Program Standards, providing for rapid implementation and deployment as a viable, accurate, and reliable means of live animal testing for CWD in cervids.

===

RESOLUTION NUMBER: 32 APPROVED

SOURCE: COMMITTEE ON CAPTIVE WILDLIFE & ALTERNATIVE LIVESTOCK

SUBJECT MATTER: Chronic Wasting Disease Testing Protocol for Wild Cervidae

BACKGROUND INFORMATION: Over the last 15 years the United States Department of Agriculture (USDA), Animal and Plant Health Inspection Service (APHIS), Veterinary Services (VS) and state regulatory officials have worked to control and prevent the spread of Chronic Wasting Disease (CWD). Producers raising CWD susceptible species can only move their animals interstate if they are in compliance with the CWD program set forth in Title 9 Code of Federal Regulations (CFR) Parts 55 & 81 that state animals must originate from herds with at least five years of CWD monitored status.

State wildlife agencies that plan and execute elk restoration projects from one state to another are moving CWD susceptible species interstate without following minimum interstate movement requirements for farmed cervidae. Instead, Title 9 CFR Part 81.3 states the source population be considered “low risk” by the receiving state and USDA APHIS.

To date, over two dozen herds of wild elk have been captured and transported to other states across the nation that follow no CWD protocol set forth in the CWD Program Standards.

The movement of CWD susceptible cervid species with unknown CWD status by state wildlife agencies can undermine the success of CWD control programs that have been in place in many states for more than 15 years. CWD has been found in 23 states. Eight of the 23 states have detected CWD in the free-ranging deer populations but not in the farmed cervid herds.

The USAHA Committee on Wildlife Diseases approved a resolution at the 2015 annual conference that requested USDA Veterinary Services to develop a guidance document for captive deer, elk, or moose captured from a wild population for interstate movement and release.

USAHA/2016 Resolution 32

APHIS has finalized and released VS Guidance Document 8000.1 “Surveillance and Testing Requirements for Interstate Transport of Wild Caught Cervids” in October 2016 but the requirement of an ante-mortem test, such as the rectal biopsy, is only optional.

Exact language is as follows:

“Optionally, a whole-herd rectal biopsy or other mutually agreed-on method of antemortem CWD test with concurrent genotyping may be performed on the assembled herd. Laboratory results must be “not detected” on all animals. Animals with untestable or incorrect location samples (i.e., samples that are autolyzed or of the wrong tissue type) may be retested.”

RESOLUTION:

The United States Animal Health Association urges the United States Department of Agriculture, Animal and Plant Health Inspection Service, Veterinary Services (VS) to amend the language in VS Guidance Document 8000.1 “Surveillance and Testing Requirements for Interstate Transport of Wild Caught Cervids”, the Chronic Wasting Disease Program Standards, and Title 9 Code of Federal Regulations (CFR) Part 81.3, (b) Animals captured for interstate movement and release, to indicate that any wild cervid of a Chronic Wasting Disease (CWD) susceptible species captured and transported interstate for release shall require:

1) A rectal biopsy or other mutually agreed-on method of antemortem CWD test with concurrent genotyping performed on the assembled herd; and

2) Documentation of a sampling scheme sufficient to detect CWD at 1 percent prevalence with 95 percent confidence in wild cervids within the defined source population from which the animals are being moved and conducted within the most recent three-year period. Such sampling scheme shall include both passive (hunter harvest and found dead) and targeted surveillance for CWD.

===

http://www.usaha.org/Portals/6/Resolutions/2016/2016%20Resolutions%20All.pdf

THURSDAY, AUGUST 18, 2016 

PROCEEDINGS ONE HUNDRED AND Nineteenth ANNUAL MEETING of the USAHA BSE, CWD, SCRAPIE, PORCINE TSE PRION October 22 28, 2015 PROCEEDINGS ONE HUNDRED AND Nineteenth ANNUAL MEETING of the UNITED STATES ANIMAL HEALTH ASSOCIATION Rhode Island Convention Center Providence, Rhode Island October 22 28, 2015

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II. C. USAHA JOINT SCIENTIFIC SESSION ABSTRACTS AND POSTERS

46

MANAGING CWD IN FARMED CERVIDS

Nicholas J. Haley

Diagnostic Medicine and Pathobiology, Kansas State University, Manhattan, KS

Chronic wasting disease (CWD) is an efficiently transmitted spongiform encephalopathy of cervids (e.g. deer, elk, and moose), and is the only known prion disease affecting both free-ranging wildlife and captive animals. The management of CWD in farmed cervids will require three avenues of research: 1) the development of a sensitive live animal test, 2) the discovery and implementation of a safe and effective vaccine strategy, and 3) with or without a vaccine, the identification and cultivation of CWD-resistant cervids. The antemortem detection of CWD and other prion diseases has proven difficult, due in part to difficulties in identifying an appropriate peripheral tissue specimen and complications with conventional test sensitivity. At present, biopsies of the recto-anal mucosalassociated lymphoid tissues (RAMALT) have shown promising sensitivity in various assays and are not impractical to collect in live animals. Nasal brush collections have likewise proven both sensitive and practical for identification of prion infections in humans, though in cervids both rectal biopsy and nasal brush collection sensitivity is critically dependent on stage of infection and genetic background. A blood test would be ideal; however rudimentary assays currently in development have yet to be evaluated blindly on naturally occurring populations or on a large scale. Vaccine development is currently underway at several institutions, though an effectively protective strategy has yet to be identified. Ultimately, genetic resistance to CWD may be a critical corner piece in the management of CWD in farmed cervids – an approach which has been used effectively to reduce the incidence of scrapie in sheep worldwide. By exploiting resistant PrP alleles in currently available white-tail and elk genetic pools, and searching various isolated populations for evidence of additional resistance mechanisms, a suitable approach to improving CWD resistance in farmed cervids may be identified. Our research has specifically sought to develop an antemortem test for CWD using amplification-based assays on collections from recent CWD depopulations, while additionally using these assays to model CWD resistance in cervid populations. Our findings from this research represent the early stages in the management and ultimately eradication of CWD in farmed deer and elk.

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REPORT OF THE COMMITTEE ON CAPTIVE WILDLIFE AND

ALTERNATIVE LIVESTOCK

Chair: Peregrine Wolff, NV

Vice Chair: Julie Napier, NE

Thomas Albert, VA; Paul Anderson, MN; James Averill, MI; Kay Backues, OK; Bill Barton, ID; Scott Bender, AZ; Warren Bluntzer, TX; Tom Bragg, NE; Rhonda Brakke, IA; Deborah Brennan, MS; Sarah Cannizzo, OR; Beth Carlson, ND; Susan Culp, TX; Donald Davis, TX; Barbara Determan, IA; Mark Drew, ID; John Fischer, GA; Nancy Frank, MI; Richard French, NH; Tam Garland, TX; Robert Gerlach, AK; Paul Gibbs, FL; Colin Gillin, OR; Michael Gilsdorf, MD; Chester Gipson, MD; Paul Grosdidier, KS; Keith Haffer, SD; Greg Hawkins, TX; Bill Hawks, DC; Kristi Henderson, IL; Terry Hensley, TX; Michael Herrin, OK; Linda Hickam, MO; Robert Hilsenroth, FL; David Hunter, MT; John Huntley, WA; Russell Iselt, TX; Donald Janssen, CA; Diane Kitchen, FL; Patrice Klein, MD; Todd Landt, IA; John Lawrence, ME; Charles Lewis, IA; Travis Lowe, MN; Mark Luedtke, MN; Bret Marsh, IN; David Marshall, NC; Chuck Massengill, MO; Robert Meyer, CO; Eric Mohlman, NE; Yvonne Nadler, IL; Jeffrey Nelson, IA; Sandra Norman, IN; Dustin Oedekoven, SD; Mitchell Palmer, IA; Janet Payeur, IA; William Pittenger, MO; Jewell Plumley, WV; Justin Roach, OK; Jonathan Roberts, LA; Keith Roehr, CO; Susan Rollo, TX; Shawn Schafer, OH; David Schmitt, IA; Dennis Schmitt, MO; Marc Schwabenlander, MN; Andy Schwartz, TX; Charly Seale, TX; Laurie Seale, WI; Daryl Simon, MN; Jonathan Sleeman, WI; David Smith, NY; Diane Stacy, LA; Kelly Straka, MO; Manoel Tamassia, NJ; Robert Temple, OH; Lee Ann Thomas, MD; Brad Thurston, IN; Jeff Turner, TX; Kathleen Turner, FL; Rick Wahlert, CO; Curt Waldvogel, OH; Ray Waters, IA; Steve Weber, CO; Skip West, OK; Ellen Wiedner, FL; Margaret Wild, CO; Kyle Wilson, TN; Nora Wineland, MO; Richard Winters, Jr., TX; Mary Wood, WY; Glen Zebarth, MN.

The Committee met on October 27, 2015, at the Rhode Island Convention Center in Providence, Rhode Island from 8:00 a.m. to 12:35 p.m. There were 39 members and 40 guests present. The one previous resolution from 2014 was addressed in the Annual update for the Cervid Health Team, Fiscal year (FY) 2015.

Charly Seale presented the report of the Subcommittee on Farmed Cervidae. The full report is found at the end of this report.

Presentations

Evaluation of a Novel Recombinant Protein Fusion Vaccine for CWD in Elk – Preliminary Data

Mary Wood, Wyoming Game and Fish Department

Chronic wasting disease (CWD) is a fatal neurologic disease of cervids which threatens both free-ranging and captive populations. Currently there are minimal management options for limiting spread of CWD. We evaluated a novel recombinant protein fusion vaccine developed by Pan-Provincial Vaccine

CAPTIVE WILDLIFE AND ALTERNATIVE LIVESTOCK

135

Enterprises (PREVENT), in elk. Thirty-eight female elk calves (Cervus elaphus) were captured on the South Park Feedground in Western Wyoming and transported to the Thorne-Williams Wildlife Research Center (TWRC). Calves were divided randomly into two groups, control (n=19) and vaccine (n=19). All elk were genotyped to determine Prnp codon 132 polymorphisms. Primary and booster vaccines were given intramuscularly six weeks apart approximately 2-3 weeks after arrival at the TWRC and yearly thereafter. Elk were challenged via natural environmental exposure to CWD at the facility. Elk were monitored daily for behavioral and physical signs of clinical CWD and were evaluated for CWD infection via rectal biopsy. All elk with clinical CWD were humanely euthanized and infection was confirmed via ELISA and immunohistochemistry. Both vaccinates and controls developed clinical CWD, with vaccinates showing a shorter survival time (p=0.014). This research is ongoing and further results are necessary before final conclusions are made.

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CAPTIVE WILDLIFE AND ALTERNATIVE LIVESTOCK

137

Rectal Biopsy as an Ante Mortem Assay for CWD: Diagnostic and Regulatory Considerations

Tracy Nichols, USDA Wildlife Services, National Wildlife Research Center

Summary:

 A considerable amount of research has been done in both deer and elk regarding rectal biopsy

 High quality rectal biopsies are needed to have reliable results

 Route and dose of CWD exposure likely influences disease incubation period

 Rectal biopsy has high specificity and moderate sensitivity that is dependent upon disease progression and genotype

 Disease progression and subsequent detection in the rectal mucosa is influenced by genetics at codon 96 in WTD and at codon 132 in elk

 CWD proliferates and trafficks faster in codon 96 GG WTD than in GS or SS animals, making detection by rectal biopsy less reliable in GS or SS deer

 Deer and elk with CWD prions present only in the retropharyngeal lymph nodes often do not have positive rectal biopsies

Annual Update for the Cervid Health Team, Fiscal Year (FY) 2015

Randy Pritchard, US Department of Agriculture, Animal and Plant Health Inspection Service, (APHIS) Veterinary Services (VS)

Voluntary Chronic Wasting Disease (CWD) Herd Certification Program The APHIS National CWD Herd Certification Program (HCP) was implemented in 2014. It is a voluntary Federal-State-industry cooperative program administered by APHIS and implemented by participating States. The program provides uniform national herd certification standards that minimize the risk of spreading CWD in farmed cervid populations. Participating States and herd owners must comply with requirements for animal identification, fencing, recordkeeping, inspections/inventories, as well as animal mortality testing and response to any CWD-exposed, suspect, and positive herds. APHIS monitors the Approved State HCPs to ensure consistency with Federal standards through annual reporting by the States. With each year of successful surveillance, participating herds will advance in status until reaching five years with no evidence of CWD, at which time herds are certified as being low-risk for CWD. Only captive cervids from enrolled herds certified as low risk for CWD may move interstate. Currently, 30 States participate in the voluntary CWD Herd Certification Program; 29 have Approved HCPs and one has Provisional Approved status. VS is working with the remaining State to transition it to Approved status. FY2015 marks the second year that Approved States have submitted their CWD HCP annual reports to APHIS. APHIS is currently reviewing these reports.

Review of CWD Program Standards

The CWD Program Standards provide clarification and guidance on how to meet CWD Herd Certification Program and interstate movement requirements.

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VS committed to an annual review of the Program Standards by representatives of the cervid industry and appropriate State and Federal agencies. VS planned to perform a review in FY2015; however, this did not occur due to the response to highly pathogenic avian influenza (HPAI). VS expects to conduct a review in FY2016.

CWD in Farmed and Wild Cervids

Retrospective Epidemiology of CWD in Farmed Cervids

In response to a 2014 USAHA Resolution, VS asked States to include a retrospective summary of the epidemiology of all positive herds with their annual HCP reports for FY2015. Unfortunately, the response to HPAI delayed completion of this summary. Five States reported information to date. A few States indicated that they did not have the resources to devote to this request. VS will continue to gather this data and to collect more comprehensive data in the future.

Summary of CWD detections

As of September 30, 2015, CWD has been confirmed in wild deer and elk in 21 US States, and in farmed cervids in 16 States. In total, 23 States have identified CWD in wild and/or farmed cervids. CWD has been reported in 70 farmed cervid herds in the United States. Confirmation of the disease in three free-ranging, wild white-tailed deer in Michigan in 2015 marked the first report of CWD in the wild cervid population in this State.

FY2015 CWD Detections in Farmed Cervids

In FY2015, CWD was identified in eight farmed cervid herds: one whitetailed deer breeding herd in Pennsylvania, one elk breeding herd in Utah (traced back from a hunting facility in Utah), one white-tailed deer (WTD) breeding herd and one WTD hunting preserve in Ohio (owned by the same producer), two WTD breeding herds in Wisconsin, one WTD and elk herd in Texas, and a second WTD herd in Texas (traced from the first positive herd in Texas). The positive animals in Utah, Ohio, and Texas represented the first reported cases of CWD in captive cervids in all three of these States. White-Tailed Deer Breeding Herd, Pennsylvania

On October 6, 2014, the National Veterinary Services Laboratories (NVSL) confirmed CWD in a 6-year-old doe from a captive WTD breeding facility in Reynoldsville, Pennsylvania. The doe was euthanized and tested because she was classified as a CWD-exposed animal that had previously resided in two trace back exposed herds. This herd was assembled in 2013 through the purchase of 16 animals from other HCP-certified herds in Pennsylvania, and had been under quarantine for receiving exposed animals from a trace back exposed herd. The remaining herd of eight WTD was depopulated with Federal indemnity on February 18, 2015, and no additional positive animals were detected. USDA collected samples for research purposes.

Elk Breeding Herd, Utah

On December 23, 2014, NVSL confirmed CWD in 3-year-old captive elk. The elk had been at a hunting park located in northern Utah, where he had resided for approximately 3 weeks prior to being hunter killed. All hunter-killed animals at the hunt park are required to be tested for CWD, and this animal

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was sampled through routine surveillance. The elk was traced back to its herd of origin, and that facility was quarantined. The herd was assembled in 1999 with bulls, and later elk cows, that originated from Colorado. Historical testing records for the herd were unavailable. The remaining 70 elk were depopulated using Federal indemnity funds on March 3, 2015, and an additional 25 elk were confirmed as CWD-positive. USDA collected samples for research purposes. White-Tailed Deer Hunting Preserve, Ohio

On October 22, 2014, NVSL confirmed CWD in a buck taken from a captive WTD deer hunting preserve in Ohio. This was the first time that CWD had been detected in Ohio. The preserve was tested as part of Ohio’s CWD monitoring program. The herd had been under quarantine since April 2014 because it was a trace-forward herd associated with a CWD-exposed herd in Pennsylvania. The positive animal was traced to its herd of origin, a captive WTD breeding herd in Pennsylvania, through DNA identity testing. On November 26, 2014, the Ohio State Veterinarian issued an Order of Destruction for animals on the hunting preserve. The State executed this Order on April 27-30, 2015. The herd of 224 WTD was depopulated and no other positives were detected. USDA did not provide Federal indemnity.

White-Tailed Deer Breeding Herd, Ohio

On March 31, 2015, NVSL confirmed CWD infection in a 5-year-old WTD doe from a captive breeding herd in Holmesville, Ohio. The index animal was received from a Wisconsin WTD farm in January 2013. The CWD-positive herd was owned by the same individual as the Ohio hunt preserve that was found to be CWD positive in October 2014. On May 22, 2015, NVSL confirmed a second positive case in the same herd - a yearling WTD doe that was a natural addition in the same breeding herd. The herd had been under quarantine since April 1, 2014 due to epidemiological linkages with two WTD herds in Pennsylvania – one a positive herd and the other a traceback exposed herd. USDA provided Federal indemnity and depopulated this herd on June 15 and 16, 2015. USDA collected samples for research purposes. NVSL confirmed CWD in 16 additional animals in the herd. Of the 16 positives, one was natural addition and the rest were purchased additions. The positive animals were purchased from February 26, 2013 through September 24, 2013, except for one purchased in 2012. Eleven purchased additions traced-back to three herds in Pennsylvania and four purchased additions traced to three other herds in Ohio.

White-Tailed Deer Breeding Herd, Wisconsin

On October 6, 2014, NVSL confirmed CWD in a 2-year-old doe born in June of 2012 that died on a Richland County farm. The facility is within the CWD management zone in Wisconsin. The remaining 51 deer were euthanized on November 20, 2014, and seven additional positives (all males born in 2012) were found. Two of these seven were purchased additions with the last added to the herd in January 2013. All sales from this herd were to shooting preserves. This premise was double fenced and had been compliant in a herd certification program for over ten years.

White-Tailed Deer Breeding Herd, Wisconsin

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On June 19, 2015, NVSL confirmed CWD in a seven-year-old female WTD from a breeding facility in Eau Claire County. The doe was a natural addition to this breeding herd. This is the first positive CWD case, captive or wild, in this county. The doe was found dead and was showing no clinical signs of CWD at the time of death. Since 2003, this herd has tested 391 animals for CWD and all had “not detected” results. In addition, 317 animals have tested “not detected” from the associated hunting preserve over the same time period. A second positive natural addition doe from this herd was confirmed positive by NVSL on September 10, 2015. Several escape episodes have occurred from this herd. The herd is currently under quarantine and plans are underway for depopulation with State indemnity.

White-Tailed Deer and Elk Breeding Herd, Texas

On June 30, 2015, NVSL confirmed CWD in a 2-year-old WTD buck from a captive WTD and elk breeding herd in Medina County, Texas, approximately 500 miles from previously reported positive free-ranging mule deer in far West Texas. This was the first time that the disease had been detected in farmed cervids in the State. The index buck was born on the premises and found dead on June 18, 2015. Over 40 high-risk deer (i.e., pen mates, dam, others) were euthanized and tested after the index case was found. The NVSL confirmed CWD infection in two of those deer. Interestingly, all three of the positive deer identified to date on this premises have the same AI sire. However, the significance of this finding is unclear. In the past five years, records indicate that 130 WTD from 33 facilities moved into the positive herd and 838 WTD moved out of the positive herd to 147 different herds. One positive WTD was found in one of these trace-out herds (see herd description below). Additionally, 23 elk were also moved from this herd to another herd in TX in 2014. All trace-outs have been intrastate except for movements to two premises in Mexico. Premises that have received deer from the index herd are under movement restrictions. VS is collaborating with animal health authorities in Mexico. VS paid indemnity and depopulated this herd on September 30, 2015, and no additional positive animals were detected. USDA collected samples for research purposes.

White-Tailed Deer Herd, Texas

On September 14, 2015 NVSL confirmed CWD from tissues from a WTD in Lavaca County, Texas. This animal was a traceout from the first CWD positive herd from June 30, 2015. Additional epidemiology is ongoing.

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Chronic Wasting Disease Risk Perception: Why Can’t We All Just Get Along?

Krysten Schuler, Animal Health Diagnostic Center, Cornell University, College of Veterinary Medicine

Additional authors: Alyssa Wetterau, Elizabeth M. Bunting, and Hussni Mohammed

Chronic wasting disease (CWD) is a disease of concern to agencies, sportsmen, and businesses dependent on cervid species. However, disease risk perceptions may vary considerably between groups on wildlife and agriculture sides. We administered an online survey using Qualtrics survey software to the state wildlife agency (n=20), state agriculture agency (n=20), federal (United States Geological Survey (USGS), USDA) and other state agencies (n=9), academics (n=5), sportsmen (n=45), and captive cervid farmers (n=13) between March 2013 and 2014 to gauge attitudes toward potential hazards for CWD transmission to wild white-tailed deer or captive cervids. Of 15 hazards, the high-ranking risks were CWD existing undetected in the wild >1 year, decreased testing without subsidies, high wild deer densities, fence line contact, intrastate movement and importation of captive deer. State wildlife and agriculture officials ranked risks higher than other groups, with captive cervid farmers 50% below the average. Of six identified

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hazard pathways, importation of live cervids and escaped cervids was the highest risk for the wildlife agency (72% probability of CWD introduction), other agency and academic professionals (45%), and sportsmen (43%,) while the agriculture agency was most concerned by wild deer migration with high deer densities (46%). Captive cervid operators were threatened by importation of wild deer parts and then infected carcasses or parts left on the landscape (29%). Professional groups ranked generalized risks similarly, particularly for wild deer, but varied on the most likely disease pathway scenario. These regulating agencies also ranked risks higher than those in the captive cervid industry. Recommendations from this study include reaching agreement that CWD is a problem and strive for prevention and containment. Adequate funding by state and federal agencies for wildlife health programs and stakeholder education, as well as improved wild deer surveillance, would decrease CWD risks. The captive cervid industry could investigate selfregulation or insurance options, in addition to the USDA program. This information could be used to further investigate risk management and communication strategies.

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Modeling CWD Resistance in Vitro

Nicholas Haley, Department of Microbiology and Immunology, Midwestern University

A review of the current science involving in vitro amplification assays which can help predict transmissible spongiform encephalopathies (TSE) resistance and how this modeling strategy may be utilized to manage CWD through host resistance.

Committee Business:

The Committee received, discussed and voted on the following five resolutions. The first four were approved and forwarded to the Committee on Resolutions. The fifth did not pass.

1. Live Animal Testing for Chronic Wasting Disease

2. Chronic Wasting Disease Program Standards - Guidance on Responding to CWD Positive Herds

3. Chronic Wasting Disease Testing Protocol for Wild Cervidae

4. Tuberculosis Testing Protocol for Farmed cervidae

5. External Review of APHIS-VS CWD Program (not approved).

There was not further business, and the meeting was adjourned.

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REPORT OF THE SUBCOMMITTEE ON FARMED CERVIDAE

Co-chairs: Charly Seale, Exotic Wildlife Association Brett Marsh, Indiana Board of Animal Health Paul Anderson, Minnesota Board of Animal Health The Subcommittee on Farmed Cervidae met on October 26, 2015 at the Rhode Island Convention Center in Providence, Rhode Island. The following committee members were present: Shawn Schafer, ND; Eric Mohlman, NE; John Fischer, GA; David Hunter, MT; Collin Gillin, OR; and Glen Zebarth, MN. Warren Bluntzer, TX and Robert Meyer, WY were not able to attend. There were a total of 80 people in attendance at the meeting.

Reports

Dr. Tracy Nichols, USDA-Animal Plant Health Inspection Service (APHIS), Wildlife Services (WS), National Wildlife Research Center (NWRC) presented new information on Ante Mortem Testing for Chronic Wasting Disease (CWD).

Dr. Nathan Shotts, Veterinary Reproduction and Genetics PLLC and Tom Van Kleef, VERGE, presented on the Verge surgical procedure for Ante Mortem CWD-Testing-Options and Implementation.

Dr. Walt Cook, Texas A&M University, presented the results of his research on drug residues in white tailed deer.

Dr. Alecia Naugle and Dr. Randy Pritchard, USDA-APHIS-Veterinary Services (VS), presented on recent cases of CWD in the United States, issues surrounding the CWD Program Standards, protocols for dealing with CWD positive herds including trace forward and trace back, current status of developing an approved live test for CWD, and issues surrounding the use of the Dual Path Platform (DPP) tuberculosis test in cervidae.

Four resolutions were drafted, discussed, voted upon and passed out of the Subcommittee on Farmed Cervidae for subsequent consideration and possible action by the full USAHA Committee on Captive Wildlife and Alternative Livestock. These resolutions are as follows:

1. Live Animal Testing for Chronic Wasting Disease

2. Chronic Wasting Disease Program Standards - Guidance on Responding to CWD positive Herds

3. Chronic Wasting Disease Testing Protocol for Wild Cervidae

4. Tuberculosis testing protocol for farmed cervidae

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287 potent and efficacious for animals is imperative for quality patient care. This includes ketamine, which is used for animal immobilization, sedation and pain management. In some areas, ketamine is the only analgesic/anesthetic agent available to the veterinary profession and additional restrictions on its use would have a significant negative impact on animal health and welfare on a global scale.

RESOLUTION:

The United States Animal Health Association (USAHA) opposes international and domestic regulatory action, specifically changes in scheduling, that would result in ketamine becoming more difficult, if not impossible, to obtain within the United States by licensed veterinarians for the authorized treatment of animals. The USAHA also requests that the Food and Drug Administration consider this resolution as they develop their comments to the World Health Organization Expert Committee.

*****

RESOLUTION NUMBER: 9 APPROVED

SOURCE: COMMITTEE ON CAPTIVE WILDLIFE AND ALTERNATIVE LIVESTOCK

SUBJECT MATTER: CHRONIC WASTING DISEASE PROGRAM STANDARDS - GUIDANCE ON RESPONDING TO CHRONIC WASTING DISEASE POSITIVE HERDS

BACKGROUND INFORMATION:

There is a need to review, revise and update the protocols for how the cervidae industry and state and federal agencies respond to chronic wasting disease (CWD) positive herds, trace back herds and trace forward herds. There is also a need to update and revise the protocols for how to release movement restrictions and reinstate herds to the appropriate herd certification program status. In order to (1) complete CWD investigations more quickly, (2) avoid unnecessary depopulation of farmed cervidae herds, and (3) avoid unnecessarily long quarantine periods, these protocols must include the use of live animal tests for CWD such as the rectal biopsy (rectoanal mucosa-associated lymphoid tissue (RAMALT)).

RESOLUTION:

The United States Animal Health Association urges the United States Department of Agriculture, Animal and Plant Health Inspection Service, Veterinary Services to amend the Chronic Wasting Disease (CWD) Program Standards by deleting all language in Part B, “Guidance on Responding to CWD Affected Herds” and rewrite Part B under the guidance of a working group of state and federal regulatory officials and representatives from the farmed cervidae industry.

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RESOLUTION NUMBER: 10 APPROVED SOURCE: COMMITTEE ON CAPTIVE WILDLIFE AND ALTERNATIVE LIVESTOCK

SUBJECT MATTER: CHRONIC WASTING DISEASE TESTING PROTOCOL FOR WILD CERVIDAE

BACKGROUND INFORMATION:

Over the last 15 years the United States Department of Agriculture (USDA), Animal and Plant Health Inspection Service (APHIS), Veterinary Services (VS) and state regulatory officials have worked to prevent and control the spread of Chronic Wasting Disease (CWD).

Producers farming CWD susceptible species can only move their animals interstate if they are in compliance with the CWD program set forth in 9 Code of Federal Regulations (CFR) Parts 55 and 81 that states animals must originate from herds with five years of CWD monitored status. State Wildlife agencies that plan and execute elk restoration projects from one state to another are moving CWD susceptible species interstate without following minimum interstate movement requirements set for farmed cervidae. Instead, CFR 81.3 states the source population be considered “low risk” by the receiving state and USDA-APHIS.

To date, over two dozen herds of wild elk have been captured and transported to other states across the nation without following the Chronic Wasting Disease protocol set forth in the CWD program for farmed cervidae. The movement of CWD susceptible cervid species with unknown CWD status by state wildlife agencies can undermine the success of CWD control programs that have been in place in many states for more than a decade. CWD has been found in 23 states. Eight of the 23 states have detected CWD in the free-ranging deer populations but not in the farmed cervid herds.

RESOLUTION:

The United States Animal Health Association urges the United States Department of Agriculture, Animal and Plant Health Inspection Service, Veterinary Services to work with stakeholders to develop a guidance document on determining chronic wasting disease risk levels of source herds for interstate cervid restoration projects.

*****

RESOLUTION NUMBER: 11 APPROVED

SOURCE: COMMITTEE ON CAPTIVE WILDLIFE AND ALTERNATIVE LIVESTOCK

SUBJECT MATTER: Live Animal Testing For Chronic Wasting Disease BACKGROUND INFORMATION:

Detection of Chronic Wasting Disease (CWD) in live animals remains an important component of CWD Prevention and Control Programs. The United

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States Animal Health Association (USAHA) and the United States Department of Agriculture (USDA) recognize this and have stated such for several years (see USAHA resolutions 14 (2011), 16 (2011), 20 (2012), 13 and 23 combined (2012), 24 (2012), and 28 (2015), with associated USDA replies).

Notwithstanding the development and evaluation of the rectoanal mucosa-associated lymphoid tissue (RAMALT) test, CWD program regulatory analysis and actions continue to rely on post-mortem tissue collections, with Immunohistochemistry (IHC) testing in the laboratory, in accordance with current USDA CWD Program Standards.

This continues to impose significant adverse impacts on the industry, the economies of local communities, and the regulatory agencies involved. Postmortem testing also limits the data and information that can be gathered and used to improve management and control of CWD.

The need for a successful live test option, with the accuracy and sensitivity equal to current post-mortem testing, is critical. A rational deployment of such a solution will require regulatory updates and guidelines to account for live testing of white-tailed deer, in both a trace-forward / traceback scenario, as well as in CWD Herd Certification and/or Management Programs.

A group of veterinarians with specific white-tailed deer experience, led by VERGE PLLC, has successfully developed an ante-mortem procedure to collect the tissues required for IHC testing, as well as enzyme linked immunosorbent assay and other approved test protocols. This solution, the VERGE procedure, provides the same medial retropharyngeal lymph node (MRPLNs) tissues with negligible morbidity or mortality, for the same regulatory lab tests as are currently in use, thus virtually eliminating the concerns for sensitivity and accuracy associated with live tests using other tissues or lab protocols.

Preliminary regulatory reviews indicate that the VERGE procedure may be employed under 9 Code of Federal Regulations 55.8, as implemented by USDA CWD Program Standards (May 2014). The VERGE group has done preliminary work on implementation guidelines for an effective live test to allow integration of the live test option into existing programs and standards for both trace-forward/trace-back and herd certification and management programs, as well as refinement and development work for rapid training and wide-spread deployment to Industry.

RESOLUTION:

The United States Animal Health Association (USAHA) urges the United States Department of Agriculture (USDA), Animal and Plant Health Inspection Service (APHIS), Veterinary Services (VS) as well as state animal health officials to continue and to expedite discussions and evaluation of ante-mortem collection procedures for medial retropharyngeal lymph node (MRPLN) tissues for the live testing for chronic wasting disease (CWD) in white-tailed deer. USAHA also urges USDA-APHIS-VS to issue a VS

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Guidance Document stating that ante-mortem collection procedures for MRPLN tissues are acceptable and authorized in accordance with current federal regulations (9 Code of Federal Regulations (CFR) 55 and 9 CFR 81) and existing federal CWD Program Standards (MAY 2014).

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Chronic Wasting Disease Research and Updates in Colorado Michael Miller, Colorado Division of Parks and Wildlife

Dr. Michael Miller, Colorado Division of Parks and Wildlife, led a brief discussion on the implications of a recent study on chronic wasting disease (CWD) host range. The Case Western study results, presented at an international prion conference in May 2015, complement other efforts to assess human susceptibility to chronic wasting disease that have been ongoing since the mid-1990s. Findings from a variety of experimental and epidemiological studies support messaging since the mid-1990s that human illness resulting from CWD exposure appears unlikely. The new study’s results are consistent with other previous and contemporary data suggesting a low probability of human prion disease resulting from CWD exposure. Dr. Miller noted that even though human illness seems unlikely, minimizing the occurrence of CWD and encouraging other precautions for minimizing human exposure to CWD may be prudent. Trends observed in Colorado since 2002 suggest increasing infection rates in affected mule deer and elk herds, with the exception of one population unit intensively managed through harvest in the early 2000s. Controlling CWD will likely need to rely on hunting in order to remain politically, socially, and fiscally sustainable. Consequently, early intervention, while infection rates are still low, may offer the best opportunity to both suppress epidemics and minimize the likelihood of hunters harvesting infected animals. Dr. Miller suggested that the timing and approaches to CWD control may deserve more attention and reconsideration than given in recent years.

Summary of Recent Chronic Wasting Disease Events in Texas Mitch Lockwood, Texas Parks and Wildlife Department

Other contributing authors: Bob Ditmar Texas Parks and Wildlife Department, Andy Schwartz, Texas Animal Health Commission

Introduction:

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 3.9 million free-ranging white-tailed deer

 700K white-tailed deer hunters

 600K white-tailed deer harvested annually

 $3.6 billion economic output for all hunting

 $2.1 billion for deer hunting

 1,300 deer breeding facilities

 > 110,000 deer in breeding facilities

 > 2,200 free-ranging deer moved annually through various permits

Texas Parks and Wildlife Department (TPWD) has been conducting chronic wasting disease (CWD) surveillance throughout the state since 2002.

Biologists have collected more than 26,000 samples from hunter-harvested deer, and others have collected more than 21,000 samples in order to meet TPWD permitting requirements, totaling almost 48,000 samples. Additionally, Texas Animal Health Commission (TAHC) has maintained a Voluntary CWD Herd Certification Program since 1995.

In 2012, CWD was discovered in two mule deer samples from far West Texas (Hueco Mountains) as a result of a targeted surveillance effort. This area is directly adjacent to a region in New Mexico with documented CWD occurrence. To date, five more positive samples have been obtained from this population through hunter harvested mule deer, indicating a disease prevalence of 10%.

Mule deer and white-tailed deer are regulated by TPWD, while other susceptible species (including elk) are regulated by the TAHC. This has generated the need for enhanced coordination and communication between these two agencies.

The TPWD/TAHC CWD Management Plan was developed by both agencies in consultation with the state’s CWD Task Force. The Task Force is comprised of wildlife biologists, deer and elk breeders, veterinarians and other animal-health experts from TPWD, TAHC, Texas Veterinary Medical Diagnostic Laboratory, Texas Department of State Health Services, Texas A&M College of Veterinary Medicine, and USDA. The plan includes mandatory check stations for susceptible species taken inside the CWD Containment Zone, which covers portions of Hudspeth, Culberson, and El Paso counties. Artificial movement of deer is prohibited in the CWD Containment Zone.

On June 30, 2015 a sample from a Medina County (area on border of southern Edwards Plateau and northern South Texas Plains ecoregions) deer breeding facility was confirmed positive for CWD. The index breeding facility participated in TAHC’s voluntary CWD Herd Certification Program, and had tested 62 of 65 mortalities prior to June 2015 (60 not detected, two location results) since permitted in 2006. There were a total of 136 adult deer in the inventory on June 30, 2015, and the herd was considered to be relatively young.

During the previous five years, 107 deer were transferred from 30 deer breeding facilities into the index facility. During that same period, 835 were transferred from the index facility to 147 different facilities including 96 deer

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breeding facilities, 46 release sites, three Deer Management Permit (DMP) sites, and two sites in Mexico.

TPWD and TAHC immediately placed a temporary moratorium on movements of all captive deer in the state, and TAHC placed a Hold Order on the 177 “Tier 1” facilities. Since then, TPWD and TAHC worked with the CWD Task Force and industry stakeholders to develop a plan to lift the moratorium on deer transfers, which includes additional CWD testing requirements in deer breeding facilities or on registered release sites. Additionally, TAHC has removed the Hold Order for 120 facilities, leaving a total 57 facilities remaining under a Hold Order as of October 16, 2015. Most deer breeding facilities were authorized to transfer deer by August 24, 2015.

Depopulation at the index facility was initiated in July 28 and completed on September 30, 2015. CWD was detected in a total of 4 (out of 136 adults) white-tailed deer in the index facility, all of which were 2-year-old bucks that were natural additions.

On September 15, 2015, CWD was confirmed in one of the trace-forward facilities, from which 84 deer had transferred out to nine different facilities (five deer breeding facilities, three release sites, and one nursing facility) since it received deer from the index herd. This resulted in seven additional Hold Orders being issued by TAHC, four of which have since been released. The CWD-positive at the trace-forward facility was also a 2-year-old buck that was born in the index facility.

In summary, CWD has been detected in a total of five captive white-tailed deer in Texas, four of which were located in the index facility, and one was located in a trace-forward facility. There are 36 deer from the 2-year-old cohort originating in the index facility that are reported to be alive in seven deer breeding facilities, and possibly as many as six deer from that cohort still alive on release sites. Additionally, there are 33 deer that traced through the index facility that are still alive in 15 deer breeding facilities, and possibly as many as 51 trace-through deer are still alive on 24 different release sites,

***and two tracethrough deer may still be alive in Mexico.

TPWD has intensified the statewide CWD surveillance efforts, with a goal to collect samples from more than 8,000 hunter-harvested deer, including 300 samples within a 5-mile radius of the index facility. TAHC will continue to pursue indemnity on exposed deer located in trace-forward facilities in an attempt to conduct a more thorough epidemiological investigation. TPWD and TAHC have committed to reevaluate movement qualification standards that apply to deer breeding facilities and release sites following the 2015-16 hunting season. Both agencies are exploring ante-mortem testing protocols, and will continue to seek guidance from experts in the field.

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Epidemiology of Recent CWD Cases in Ohio

Susan Skorupski, USDA-APHIS-VS

Background

Ohio has had a voluntary Chronic Wasting Disease (CWD) Herd Certification Program for all cervidae for at least 12 years. Ohio has 331 cervidae herds in the CWD monitoring program with 256 at Certified level. In October 2012, Ohio White Tail Deer rule became effective. It includes several categories of white tail deer operations. Monitored herds cannot sell or give away animals and includes hunting preserves. Under this rule, hunting preserves cannot move live animals from the premises and must annually sample 30 animals or 30% of harvested deer, based on the number of deer harvested during the previous year. Herds with Status are herds enrolled in the CWD Certification Program but not yet at certified level. Certified Status Herds are enrolled in the CWD monitoring program and have reached certified status. Ohio has 135 Monitored Herds, including 24 hunting preserves, 75 Herds with Status, and 256 Certified Status herds.

Ohio’s approach to infected animals and associated animals and herds Infected herd – herd where a CWD infected animal resided when the test positive sample was collected. Herd quarantined.

Exposed herd – any herd where an animal that tested CWD positive has resided within the five years before the CWD diagnosis. Whole herd quarantined

Herd that contains an exposed animal – whole herd quarantined unless epidemiology information suggests the animal is of lower risk of spreading CWD.

Exposed animal – animal that was exposed to the CWD infected animal any time during the five years prior to when the animal died or was euthanized and sampled/tested positive for CWD.

Recent CWD History in Ohio

a. Pennsylvania traces

In the spring of 2014, Ohio received information on traces associated with CWD positive cases in Pennsylvania. Three Ohio herds were designated as Exposed herds because positive deer from infected herds in Pennsylvania had been in the Ohio herds during the previous five years. Fifty Ohio herds received 256 exposed deer from the five Pennsylvania herds and three Ohio exposed herds. Eighty-five of those animals were tested with Not Detected results in Ohio herds. Sixty-six animals were traced to Out of State herds. That leaves 101 animals either standing in quarantined herds or not tested when they died or were harvested. Eighteen herds/preserves remain under quarantine.

b. First CWD positive found in Ohio

On October 22, 2014, National Veterinary Services Laboratory (NVSL) confirmed a CWD positive result for a 2.5-year-old buck killed at a hunting preserve in Holmes County Ohio on October 2, 2014. The hunting preserve had been under quarantine since April 1, 2014 because of Pennsylvania traces and was required to do 100% sampling of harvested deer. The positive animal

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had official identification tracing the animal to a CWD certified Pennsylvania herd. Records including a Certificate of Veterinary Inspection (CVI) indicate the animal moved to Ohio March 13, 2013. Genetic testing was conducted to support the accuracy of the trace to the Pennsylvania herd. This herd was depopulated without indemnity April 27-29, 2015. Two hundred twenty-four animals were depopulated at owner expense and sampled for CWD. All tests had Not Detected results for CWD. The premises was evaluated as a minimally contaminated facility. No cervidae have been added to the premises at this time.

The owner of the hunting preserve business also owns or is associated with breeding herds at other locations in Holmes County.

c. Second positive premises in Ohio

A white tail deer breeding herd owned by the same person who owned the CWD positive hunting preserve was designated as a positive herd in the spring of 2015. A CWD positive animal was sampled on March 12, 2015 and reported on March 25, 2015. The animal was a five-year-old whitetail doe purchased from a Wisconsin herd in February 2013. A second CWD positive animal was reported from this herd on May 22, 2015. This animal was a 1.5- year-old natural addition doe.

This herd was initially established in the fall of 2012 with the purchase of a CWD certified herd from the estate of a deceased owner. In the spring and fall of 2013, additional animals were added from at least nine Ohio herds, one Wisconsin herd, 17 Pennsylvania herds, and three Indiana herds. This herd had been quarantined since April 1, 2014 because of traces from several CWD exposed or positive herds in Pennsylvania, including the herd that was the source of the CWD positive deer in the Ohio hunting preserve. It had received over 120 animals from these herds.

On June 15 and 16, this herd was depopulated with federal indemnity. Samples were collected for research purposes. Two hundred forty-one animals including 44 fawns were euthanized, sampled and tested. Sixteen additional positive were identified. They originated from five Ohio CWD certified herds and four Pennsylvania CWD certified herds. One of the Ohio herds was the herd that was used to initially establish this herd. One positive animal was over 60 months of age so that Ohio herd was not designated as an exposed herd. The other three Ohio herds were quarantined as exposed herds.

Records reviews identified 334 exposed animals associated with Ohio exposed herds. Forty-two Ohio herds containing these animals were quarantined. They have remained under quarantine until the quarantined animal(s) are euthanized and tested Not Detected for CWD or 60 months have passed since animals entered the herd. From Ohio Exposed Herd 1, 56 animals moved to 21 Ohio herds and 83 animals moved out of state. Twentyseven animals were either already dead and tested with CWD Not Detected results or have since been tested with CWD Not Detected results. From Ohio Exposed Herd 2, 76 animals moved to 16 Ohio herds and 94 animals moved out of state. Twenty-five animals were either already dead and tested with

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CWD Not Detected results or have since been tested with CWD Not Detected results. From Oho Exposed Herd 3, 21 animals moved to five Ohio herds and four animals moved out of state. Seven animals were either already dead and tested with CWD Not Detected results or have since been tested with CWD Not Detected results. Ohio received two exposed animals from the exposed herd in Pennsylvania associated with this case. In summary, 334 exposed animals were identified and traced to 40 Ohio herds. Fifty-nine of those in Ohio have been tested with Not Detected CWD results. One hundred eighty-one have been traced out of state and 94 are still standing in 26 quarantined herds/hunting preserves.

Ohio Exposed Herd 1 has been in the CWD Certification Program since September 2003 and has an inventory as of 48 head over one-year-old. Ohio Exposed Herd 2 has been in the CWD Certification Program since October 2003 and has an inventory of 93 animals. Ohio Exposed Herd 3 has been in the CWD Certification Program since February 2009 but started with a status date of May 2001 and has an inventory of 17 deer.

In addition, Ohio received reports of 72 exposed deer from out of state (OOS) Exposed herds traced to 18 Ohio herds. Eighteen of those animals had moved to out of state herds. Thirty animals were tested in Ohio with Not Detected results. Twelve animals remain in Seven quarantined herds. The summary of all traces associated with positive cases in Ohio and Pennsylvania in 2014 – 2015 are:

 Total exposed animals traced to Ohio: 661

 Total tested Not Detected: 176

 Total animals traced to Out of State Premises: 265

 Total premises initially quarantined: 87

 Total premises remaining quarantined: 40

 Total Hunting Preserves quarantined: 10

USDA Cervid Health Program Updates

Randy Pritchard, USDA-APHIS, Veterinary Services (VS)

Voluntary Chronic Wasting Disease (CWD) Herd Certification Program

The APHIS National CWD Herd Certification Program (HCP) was implemented in 2014. It is a voluntary Federal-State-industry cooperative program administered by APHIS and implemented by participating States. The program provides uniform national herd certification standards that minimize the risk of spreading CWD in farmed cervid populations. Participating States and herd owners must comply with requirements for animal identification, fencing, recordkeeping, inspections/inventories, as well as animal mortality testing and response to any CWD-exposed, suspect, and positive herds. APHIS monitors the Approved State HCPs to ensure consistency with Federal standards through annual reporting by the States. With each year of successful surveillance, participating herds will advance in status until reaching five years with no evidence of CWD, at which time herds are certified as being low-risk for CWD. Only captive cervids from enrolled herds certified as low risk for CWD may move interstate. Currently, 30 States participate in the voluntary CWD

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Herd Certification Program; 29 have Approved HCPs and one has Provisional Approved status. VS is working with the remaining State to transition it to Approved status. FY2015 marks the second year that Approved States have submitted their CWD HCP annual reports to APHIS. APHIS is currently reviewing these reports.

Review of CWD Program Standards

The CWD Program Standards provide clarification and guidance on how to meet CWD Herd Certification Program and interstate movement requirements. VS committed to an annual review of the Program Standards by representatives of the cervid industry and appropriate State and Federal agencies. VS planned to perform a review in FY2015; however, this did not occur due to the response to highly pathogenic avian influenza (HPAI). VS expects to conduct a review in FY2016.

CWD in Farmed and Wild Cervids

Retrospective Epidemiology of CWD in Farmed Cervids: In response to a 2014 USAHA Resolution, VS asked States to include a retrospective summary of the epidemiology of all positive herds with their annual HCP reports for FY2015. Unfortunately, the response to HPAI delayed completion of this summary. Five States reported information to date. A few States indicated that they did not have the resources to devote to this request. VS will continue to gather this data and to collect more comprehensive data in the future. Summary of CWD detections. As of September 30, 2015, CWD has been confirmed in wild deer and elk in 21 US States, and in farmed cervids in 16 States. In total, 23 States have identified CWD in wild and/or farmed cervids.

CWD has been reported in 70 farmed cervid herds in the United States.

Confirmation of the disease in three free-ranging, wild white-tailed deer in Michigan in 2015 marked the first report of CWD in the wild cervid population in this State.

FY2015 CWD Detections in Farmed Cervids: In FY2015, CWD was identified in eight farmed cervid herds: one white-tailed deer breeding herd in Pennsylvania, one elk breeding herd in Utah (traced back from a hunting facility in Utah), one white-tailed deer (WTD) breeding herd and one WTD hunting preserve in Ohio (owned by the same producer), two WTD breeding herds in Wisconsin, one WTD and elk herd in Texas, and a second WTD herd in Texas (traced from the first positive herd in Texas). The positive animals in Utah, Ohio, and Texas represented the first reported cases of CWD in captive cervids in all three of these States.

White-Tailed Deer Breeding Herd, Pennsylvania: On October 6, 2014, the National Veterinary Services Laboratories (NVSL) confirmed CWD in a 6- year-old doe from a captive WTD breeding facility in Reynoldsville, Pennsylvania. The doe was euthanized and tested because she was classified as a CWD-exposed animal that had previously resided in two trace back exposed herds. This herd was assembled in 2013 through the purchase of 16 animals from other HCP-certified herds in Pennsylvania, and had been under quarantine for receiving exposed animals from a trace back exposed herd. The remaining herd of eight WTD was depopulated with Federal indemnity on

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February 18, 2015, and no additional positive animals were detected. USDA collected samples for research purposes.

Elk Breeding Herd, Utah: On December 23, 2014, NVSL confirmed CWD in 3-year-old captive elk. The elk had been at a hunting park located in northern Utah, where he had resided for approximately three weeks prior to being hunter killed. All hunter-killed animals at the hunt park are required to be tested for CWD, and this animal was sampled through routine surveillance. The elk was traced back to its herd of origin, and that facility was quarantined. The herd was assembled in 1999 with bulls, and later elk cows, that originated from Colorado. Historical testing records for the herd were unavailable. The remaining 70 elk were depopulated using Federal indemnity funds on March 3, 2015, and an additional 25 elk were confirmed as CWD-positive. USDA collected samples for research purposes.

White-Tailed Deer Hunting Preserve, Ohio: On October 22, 2014, NVSL confirmed CWD in a buck taken from a captive WTD deer hunting preserve in Ohio. This was the first time that CWD had been detected in Ohio. The preserve was tested as part of Ohio’s CWD monitoring program. The herd had been under quarantine since April 2014 because it was a trace-forward herd associated with a CWD-exposed herd in Pennsylvania. The positive animal was traced to its herd of origin, a captive WTD breeding herd in Pennsylvania, through DNA identity testing. On November 26, 2014, the Ohio State Veterinarian issued an Order of Destruction for animals on the hunting preserve. The State executed this Order on April 27-30, 2015. The herd of 224 WTD was depopulated and no other positives were detected. USDA did not provide Federal indemnity.

White-Tailed Deer Breeding Herd, Ohio: On March 31, 2015, NVSL confirmed CWD infection in a 5-year-old WTD doe from a captive breeding herd in Holmesville, Ohio. The index animal was received from a Wisconsin WTD farm in January 2013. The CWD-positive herd was owned by the same individual as the Ohio hunt preserve that was found to be CWD positive in October 2014. On May 22, 2015, NVSL confirmed a second positive case in the same herd -- a yearling WTD doe that was a natural addition in the same breeding herd. The herd had been under quarantine since April 1, 2014 due to epidemiological linkages with two WTD herds in Pennsylvania – one a positive herd and the other a traceback exposed herd. USDA provided Federal indemnity and depopulated this herd on June 15 and 16, 2015. USDA collected samples for research purposes. NVSL confirmed CWD in 16 additional animals in the herd. Of the 16 positives, one was natural addition and the rest were purchased additions. The positive animals were purchased from February 26, 2013 through September 24, 2013, except for one purchased in 2012. Eleven purchased additions traced-back to three herds in Pennsylvania and four purchased additions traced to three other herds in Ohio.

White-Tailed Deer Breeding Herd, Wisconsin:

On October 6, 2014, NVSL confirmed CWD in a 2-year-old doe born in June of 2012 that died on a Richland County farm. The facility is within the CWD management zone in Wisconsin. The remaining 51 deer were euthanized on November 20, 2014,

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and seven additional positives (all males born in 2012) were found. Two of these seven were purchased additions with the last added to the herd in January 2013. All sales from this herd were to shooting preserves. This premises was double fenced and had been compliant in a herd certification program for over ten years.

White-Tailed Deer Breeding Herd, Wisconsin: On June 19, 2015, NVSL confirmed CWD in a 7-year-old female WTD from a breeding facility in Eau Claire County. The doe was a natural addition to this breeding herd. This is the first positive CWD case, captive or wild, in this county. The doe was found dead and was showing no clinical signs of CWD at the time of death. Since 2003, this herd has tested 391 animals for CWD and all had “not detected” results. In addition, 317 animals have tested “not detected” from the associated hunting preserve over the same time period. A second positive natural addition doe from this herd was confirmed positive by NVSL on September 10, 2015. Several escape episodes have occurred from this herd. The herd is currently under quarantine and plans are underway for depopulation with State indemnity.

White-Tailed Deer and Elk Breeding Herd, Texas:

On June 30, 2015, NVSL confirmed CWD in a 2-year-old WTD buck from a captive WTD and elk breeding herd in Medina County, Texas, approximately 500 miles from previously reported positive free-ranging mule deer in far West Texas. This was the first time that the disease had been detected in farmed cervids in the State. The index buck was born on the premises and found dead on June 18, 2015. Over 40 high-risk deer (i.e., pen mates, dam, others) were euthanized and tested after the index case was found. The NVSL confirmed CWD infection in two of those deer. Interestingly, all three of the positive deer identified to date on this premises have the same AI sire. However, the significance of this finding is unclear. In the past five years, records indicate that 130 WTD from 33 facilities moved into the positive herd and 838 WTD moved out of the positive herd to 147 different herds. One positive WTD was found in one of these traceout herds (see herd description below). Additionally, 23 elk were also moved from this herd to another herd in Texas in 2014. All trace-outs have been intrastate except for movements to two premises in Mexico. Premises that have received deer from the index herd are under movement restrictions. VS is collaborating with animal health authorities in Mexico. VS paid indemnity and depopulated this herd on September 30, 2015, and no additional positive animals were detected. USDA collected samples for research purposes. White-Tailed Deer Herd, Texas: On September 14, 2015 NVSL confirmed CWD from tissues from a WTD in Lavaca County, Texas. This animal was a traceout from the first CWD positive herd from June 30, 2015. Additional epidemiology is ongoing.

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Cervid Health Program Budget

The Cervid Health Program includes the CWD herd certification program and the cervid TB program. It is funded through the Equine, Cervid, and Small Ruminant Line Item. In FY2015, the Cervid Health Program was appropriated $3.0 million by Congress for cervid health activities. This funding was allocated as follows:

 Indemnity − $1.1 million for CWD and cervid TB (an additional $230,000 was provided to support herd depopulation activities in Texas).

 CWD Research − $200,000 to support USDA Wildlife Services (WS) research for development of CWD live animal diagnostic testing.

 Cervid Health Program − $1.2 million for general program support (primarily field activities).

APHIS anticipates the FY2016 Cervid Health Program funding will remain at FY2015 levels.

Committee Business:

One resolution was proposed by a committee member titled Chronic Wasting Disease Testing Protocol for Wild Cervidae proposing the United States Animal Health Association (USAHA) urge the USDA to amend CFR 81.3 (b); proposing wild cervids captured for interstate movement and release, have two forms of identification, one of which that is official identification, must be PrP genotyped for chronic wasting disease resistance, tested for chronic wasting disease using a rectal biopsy test. The committee discussed and debated the terms and science related to this resolution proposal including that currently there is no science indicating there are “genotype resistant” cervids to acquiring the CWD prion. The term “resistant” is miss-leading. There are only different cervid genotypes that acquire the infectious prions at different rates and show clinical signs at variable rates, some at prolonged periods after acquiring the prion or they are slow to accumulate detectable levels. Since all infected animals would be presumed to be capable of shedding the prions into the environment, genotypes with clinical “resistance” or prolonged indication of clinical presentation of the disease, may well potentially be considered prolonged shedders of the prion. Additionally, there was discussion put forth by several committee members concerning the lack of regulatory validation of the rectal biopsy test. Also, the test can only be used on young animals and there is significant test sensitivity and specificity variability between cervid species when using this test. A new motion to the proposed resolution was to table this resolution, reword the resolution potentially to be a recommendation for USDA to provide a guidance document to the states for surveillance of CWD on interstate translocations of wild cervids. It was proposed that this new resolution/recommendation be discussed during the Farmed Cervid Subcommittee and forward then to the Committee on Captive Wildlife and

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Alternative Livestock. The motion was proposed by member Charlie Seale and seconded by member Sean Shaffer which was passed by committee. The Committee on Wildlife Diseases adjourned at 5:15 p.m.

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NOMINATIONS AND RESOLUTIONS 291

RESOLUTION NUMBER: 13 APPROVED SOURCE: COMMITTEE ON SCRAPIE SUBJECT MATTER: SCRAPIE RULE BACKGROUND INFORMATION:

While the Scrapie Eradication Program has been very successful in decreasing the prevalence of scrapie in the United States, eradication has not yet been achieved in sheep or goats. Improved traceability and surveillance are needed to detect the last remaining cases of scrapie, proving to our trading partners that the United States is scrapie-free thus adding approximately $50 million in export value. Mandatory identification of sheep has allowed slaughter surveillance to be the key in reducing the prevalence of scrapie in sheep by 85%. Slaughter surveillance of goats has been problematic because currently only 50% of mature goats are officially identified at slaughter, making it impossible to conduct effective surveillance. A proposed rule to amend 9 Code of Federal Regulations Parts 54 and 79 has been published. This proposed rule addresses new standards for official identification and traceability for goats as well as other gaps in the regulation. To succeed in the eradication of scrapie, it is imperative that this rule be promptly finalized after appropriate review and consideration of comments.

RESOLUTION:

The United States Animal Health Association urges the United States Secretary of Agriculture to publish a final scrapie rule in early 2016. The proposed rule, which provides for improved traceability for goats and addresses other gaps in the current regulation, is a critically important element needed to achieve scrapie eradication in the United States.

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REPORT OF THE COMMITTEE ON SCRAPIE

Chair: Kristine Petrini, MN Vice Chair: Cheryl Miller, IN James Averill, MI; Scott Bender, AZ; Deborah Brennan, MS; Minden Buswell, WA; Beth Carlson, ND; John Clifford, DC; Walter Cook, TX; Stephen Crawford, NH; Susan Culp, TX; Ignacio dela Cruz, MP; William Edmiston, TX; Anita Edmondson, CA; Dee Ellis, TX; Keith Forbes, NV; Larry Forgey, MO; Michael Gilsdorf, MD; William Hartmann, MN; Carl Heckendorf, CO; Amy Hendrickson, WY; Russell Iselt, TX; Paul Jones, AL; Susan Keller, ND; Eileen Kuhlmann, MN; James Leafstedt, SD; Mary Lis, CT; Jim Logan, WY; Shirley McKenzie, NC; Ronald Miller, PA; Elisabeth Patton, WI; Jewell Plumley, WV; Justin Roach, OK; Suelee Robbe-Austerman, IA; Paul Rodgers, WV; Susan Rollo, TX; Joan Dean Rowe, CA; Ben Smith, WA; Scott Stuart, CO; Diane Sutton, MD; Manoel Tamassia, NJ; Jeff Turner, TX; Stephen White, WA; Nora Wineland, MO; David Winters, TX; Cindy Wolf, MN.

The Committee met on October 27, 2015 in Room 553 of the Rhode Island Convention Center in Providence, Rhode Island from 9:00 a.m. to 12:06 p.m. There were 18 members and 20 guests present.

Time-Specific Paper

Dr. Diane Sutton, presented a time-specific paper on the Newly Published Proposed Revisions to Scrapie Rules 9 CFR, parts 54 and 79. Dr. Sutton summarized the changes and explained the process for submitting comments. The Committee discussed some of the highlights of the proposed changes. A full summary is included at the end of this report.

Presentations and Reports

USDA-APHIS Scrapie Program Update and Scrapie Surveillance Projects Diane Sutton, USDA-APHIS, Veterinary Services (VS)

Scrapie Eradication Program Results

 The National Scrapie Eradication Program continued to make progress in FY2015.

 At the end of FY2014, the percent of cull sheep found positive at slaughter and adjusted for face color was 0.018 percent and is currently at 0.004 percent for FY 2015. This measure has decreased by 80 percent compared to FY2014 and by 98 percent compared to FY2003.

 Three source flocks and three infected flocks were designated in FY2014. One infected and three source flocks have been designated in FY2015, a decrease of 30 percent.

 In November 2014, the first positive goat found through regulatory scrapie slaughter surveillance (RSSS) was identified. Based on the goats sampled at slaughter to date, the prevalence of scrapie in US cull goats (2003 –

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2015) was 0.0037 percent with an upper 95 percent confidence limit of 0.0097 percent.

 In FY2015 there was a decrease in the number of States meeting their sampling minimums for sheep and goats. This was likely due in part to the impact of highly pathogenic avian influenza (HPAI) response on resources.

Slaughter Surveillance

As of September 30, 2015, 40,862 animals were sampled for scrapie testing in FY2015:

• 38,671 RSSS samples and 2,191 on-farm samples;

• Of which 33,698 were sheep and 7,164 were goats.

Scrapie Surveillance Plan

 Implementation FY2016

o States with RSSS collection sites will continue to sample all targeted sheep and goats.

o The annual State-of-origin sampling minimum for sheep is 20 percent of the number required to detect a scrapie prevalence of 0.1 percent with 95 percent confidence or 1 percent of the breeding flock in the State, whichever is less. The objective is to sample sufficient sheep in a 5-year period to detect a scrapie prevalence of 0.1 percent with 95 percent confidence or 5 percent of the breeding flock in the State, whichever is less.

o The annual State-of-origin sampling minimum for goats is determined based on the States’ goat scrapie case incidence.

o If a State has not had a goat scrapie case in the previous ten years, its annual goat sampling minimum is its prorated share of 3,000 samples, based on its proportion of the US goat population as determined by the National Agricultural Statistics Service (NASS) Sheep and Goat annual report.

o If a State has had a goat scrapie case in the previous ten years, its annual goat sampling minimum is determined using the same method as is used for determining its annual sheep sampling minimum.

Note: These are minimums. Plan is to continue to collect samples from the maximum number of targeted animals given the available budget.

ID Compliance:

 All scrapie positive animals in FY2015 were traced back to their flock of origin.

Proposed Rules Planned for Publication:

 VS published revisions to nine Code of Federal Regulations (CFR) parts 54 and 79. The proposed changes are intended to improving the effectiveness and cost efficiency of surveillance and to increase animal identification compliance by addressing gaps in identification and by requiring States to meet reasonable surveillance targets to remain consistent States. States must meet these targets for VS to demonstrate geographically appropriate surveillance to meet the criteria for freedom and have confidence that all of the remaining cases have been found.

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 The rule would propose to:

o Give the APHIS Administrator authority to relieve requirements for sheep and goats exposed to scrapie types, such as Nor98-like, that do not pose a significant risk of transmission;

o Increase flexibility in how investigations can be conducted and allow the epidemiology in a specific flock to be given more consideration in determining flock and animal status;

o Add a genetic-based approach to regulation;

o Make goat identification requirements similar to those for sheep to support ongoing slaughter surveillance in goats (no changes will be made in the consistent State requirements regarding identification of goats in intrastate commerce);

o Tighten the definition of slaughter channels;

o Expand the individual identification requirement to all sexually intact animals unless moving as a group/lot (allows mixed-source groups moving in slaughter channels at under 18 months);

o Limit the use of tattoos and implants to animals not moving through markets and not in slaughter channels; and

o Reduce recordkeeping requirements by making them similar to the current uniform methods and rules compliance guidance.

 APHIS is also revising its scrapie import regulations to bring them more in line with the OIE scrapie chapter. This will ensure that we meet OIE criteria for free status and prevent the reintroduction of scrapie after free status is achieved.

Scrapie Flock Certification Program (SFCP)

 Implementation of the revised Scrapie Flock Certification Program (SFCP) in FY 2014 has increased the efficacy of the program while reducing program costs.

 At the end of FY2015 there were 441 producers enrolled in the program.

TSE: An Update

Linda Detwiler, Department of Pathobiology and Population Medicine, Mississippi State University, College of Veterinary Medicine Dr. Detwiler reviewed and discussed recent transmissible spongiform encephalopathy research relevant to scrapie.

Update on Scrapie Research from the Animal Disease Research Unit David Schneider, Animal Disease Research Unit, Agricultural Research Service (ARS), USDA

The USDA-ARS unit in Pullman, Washington, conducts an integrated research program involving studies on scrapie diagnostics, the role of prion protein (PRNP) genetics, and modes of transmission in domestic sheep and goats. In this update, we report on a comparison between sheep and goats on factors that affect the diagnostic quality of rectal biopsy; progress on determination of the role of PRNP genetics on the susceptibility, disease progression, and impact on diagnostics in goats inoculated with classical

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scrapie; progress in evaluating potential modes of transmission for atypical (Nor98-like) scrapie in sheep and classical scrapie via goat’s milk; and use of mouse models to discriminate sheep and goats with classical scrapie versus experimental chronic wasting disease.

Biopsy of the rectal mucosa is a sensitive and safe technique used worldwide in the live-animal diagnosis of classical scrapie infection in sheep and goats, but which is sometimes limited when biopsy samples contain insufficient follicles. Reported rates of biopsies with insufficient follicles have ranged from 3% to 33%, with a significantly higher rate reported in goats and indicating the number of follicles may depend on both procedural and animal factors. Using live-animal biopsies obtained from a cohort of research sheep and goats, we determined that laboratory handling had a minor effect on the number of the follicles observed in each section. The most important factor was the animal’s age at the time of biopsy, decreasing at a steady rate of 13 percent per year during the first four years of the animal’s life. There was no left versus right side difference in the age-related decline in follicle number and the findings were the same between sheep and goats.

Regarding prion protein genetics, we continue to monitor goats of different genotypes orally inoculated at birth with classical scrapie prions derived from naturally infected goats. Goats with the highly susceptible genotype all developed clinical disease within 24 months. Goats with the less susceptible or long incubation genetics (S146 or K222) have remained clinically normal with no evidence of prions in rectal biopsy tissues. These goats will be monitored for the duration of the natural lifespan. In addition, a related study was completed which demonstrates a doubly prolonged incubation period in inoculated goats bearing the GS127 polymorphism.

Regarding our studies on modes of prion transmission, we very recently completed and are finalizing analyses for a 7-year study on Nor98-like scrapie in breeding ewes. Ewes were experimentally inoculated with brain homogenate obtained from a US sheep with clinical Nor98-like scrapie. Recipient ewes were bred annually to examine the placenta for evidence of a transmissible agent. One recipient ewe developed an unrelated disease in her fifth year of scrapie incubation. At postmortem examination, a Nor98-like pattern of misfolded prion protein, PrP-Sc, accumulation was observed. Similar findings were recently confirmed through postmortem examination of the other three ewes in the seventh year of scrapie incubation. These results confirm that inoculation of these ewes was successful. Not all placental tissue analyses have yet been completed, but there has been no evidence of placental accumulation of PrP-Sc out to the sixth year of infection.

We have recently confirmed that the classical scrapie prions which accumulate in the placenta of goats are infectious to sheep. Similarly, transmission to sheep has also occurred via the milk of infected goats. Thus, both the placenta and milk of infected goats are significant transmission risks to sheep.

Finally, we are nearing the completion of a study to determine if transgenic mice can be used to differentiate the origin of prions in new cases of scrapie

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disease in sheep and goats raised in regions with endemic chronic wasting disease (CWD) in cervids. The results show that transgenic mice bearing a susceptible prion protein are readily susceptible to classical scrapie prions derived from naturally infected sheep and goats but not to CWD prions derived from naturally infected cervids. The converse was true for transgenic mice bearing a susceptible cervid prion protein. Both types of mice were only intermediately susceptible to CWD prions derived from experimentally infected sheep. Thus, to date, the results suggest this bioassay model can discriminate between these sources of prions in new cases of prion disease in small ruminants from regions in which CWD is endemic in cervid populations.

Committee Business:

The Committee reviewed its mission statement and no alterations were suggested. There was a discussion about whether the Committee on Scrapie and the Committee on Sheep and Goats should be combined. The Committee members indicated that at this time the two committees should remain separate.

The Committee reviewed its 2014 Resolution that urged the Secretary of Agriculture to quickly publish and finalize the proposed rule amending 9 CFR Parts 54 and 79. This proposed rule is now published and open for public comment. The Committee passed a new resolution urging the Secretary of Agriculture to promptly publish a final scrapie rule in early 2016 following the appropriate review and comment period.

Note: Prior to the Committee on Scrapie meeting the following presentation was given by Dr. Diane Sutton as part of the National Scrapie Oversight Board meeting. A summary is included below supplemental to the Committee Report.

SFCP Participation

 As of September 30, 2015 there were 441 participating flocks in the SFCP.

o 277 Select Monitored

o 142 Export Monitored

o 22 Export Certified

 In FY2015 four Export Monitored flocks advanced to Export Certified.

 48 sheep breeds and 17 goat breeds are represented in the SFCP.

 As of September 30, 2015 there are active State SFCP boards in nine States.

Canada’s Import Requirements

 APHIS still anticipates a change in Canada’s import requirements, exact timeline of publication of new requirements not yet determined.

 The change will be an increase in the minimum time in status in the Export Category for eligibility to import US sheep or Goats into Canada.

Export Monitored Flock FY 2015 Review

 Export Monitored flocks in Standard or Alternative two sampling protocols must meet sampling thresholds to reach six years of status (Standard=15; Alternative 2=at least 50% foundation flock). In June 2015 Export

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Monitored flocks with six or more years of status were reviewed. Ninety-six flocks were reviewed, and of these:

o APHIS identified 28 flocks with six or more years of status that had not met the sampling threshold;

o The status dates for these flocks were reset to five years; and

o Notification letters were sent to producers explaining their new status dates and steps they can take to regain six years of status by January 1, 2016.

 APHIS will continue to monitor flocks that are approaching six years. They must meet threshold and notify those that need to take action to maintain their status date.

Select Category

 Participation in the Select category was lower in FY2015 than in FY2014.

 APHIS’ goal in FY2016 is to increase participation in this category, thereby increasing the SFCP contribution to scrapie on-farm surveillance.

 APHIS will also review Select Monitored flocks in FY2016 for compliance with sampling requirements.

SFCP Standards

In FY2015, APHIS revised the SFCP Standards. The revised standards are currently in clearance and are expected to be published in FY2016.

Updates to the SFCP Standards included the following items:

 In the Select category, animals collected through Regulatory Scrapie Slaughter Surveillance (RSSS) will count toward the sampling requirement if at least ten animals are collected through RSSS in the same sampling period.

 Sampling requirements in genetically resistant Export Monitored flocks following the Standard sampling protocol: if there are no genetically susceptible animals in the flock (i.e. the flock is composed entirely of QR/RR ewes, RR rams, and no goats), the annual, 6-year, and 7-year sampling requirements are waived (assuming all other sampling requirements are met).

 Criteria for exempting lambs born in genetically resistant flocks from genotyping for Standard and Alternative 1 sampling protocol: if there are no genetically susceptible animals in the flock and the owner only has mature RR rams on the premises from that point forward lambs do not need to be genotyped. Note: these conditions will be confirmed at each subsequent annual inspection, and if an inspector believes at any time that one or more of the animals in the flock may be a QQ animal, the inspector will require that the animal(s) be officially genotyped.

 How to treat “Lost to Inventory” animals in Export Monitored flocks following the Alternative 1 sampling protocol:

o The flock owner may elect to switch to the standard sampling protocol, and the flock’s status date will be reset to the lesser of the flock’s current status date or 12 months of status for each test eligible animal sampled and must meet the additional sampling

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requirements of the standard sampling protocol to retain more than five years in status; or

o The flock owner may elect to stay in the Alternative 1 category, and the flock’s status date will be reset to the date the VS office was notified (or the lost to inventory animal became known to the VS office) that the animal was lost to inventory.

 Animals from Inconsistent States not in slaughter channels must be from either an Export Monitored/Export Certified flock or from a Select Monitored flock in which it was born. There are no changes for animals in slaughter channels.

 Retesting animals to meet the annual sampling requirement:

o If a flock following the Standard sampling protocol has live-animal tested all genetically susceptible test eligible animals at least once and must test an additional animal to meet the annual sampling requirement, previously tested animals can be repeat live-animal tested.

o If all genetically susceptible animals in the flock have been live animal tested four times, the annual sampling requirement is waived.

 Export category flocks must report the use of milk/colostrum from a lower status flock.

 Animals tested within 12 months of another animal being “Lost to Inventory” can meet the lost to inventory sampling requirement in Export Certified flocks if the flock had already tested 30 animals (this does not apply to “Found Dead” animals).

 How to treat previously live-animal tested “Found Dead” and “Lost to Inventory” animals in Export Monitored flocks:

o Lost to inventory – if the animal had been tested in the previous 12 months, no change in status and no additional animals need to be tested (and if the flock is following the Alternative 1 sampling protocol it does not have to switch to the Standard sampling protocol).

o Found dead – APHIS will determine if the animal reasonably could have been sampled. If so, the animal will be treated as any other found dead. If not the animal is considered lost to inventory and will treated the same as other lost to inventory animals.

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REVIEW AND DISCUSSION OF NEWLY PUBLISHED REVISIONS TO SCRAPIE RULES 9 CFR, PARTS 54 AND 7

Diane Sutton

USDA-APHIS-Veterinary Services (VS)

Overview

The US Department of Agriculture’s (USDA) Animal and Plant Health Inspection Service (APHIS) is proposing changes to its existing scrapie regulations. Scrapie is a degenerative and eventually fatal prion disease of sheep and goats, and APHIS regulations help prevent its spread and support its eventual eradication.

This is a synopsis of the proposed rule and should not be considered definitive. Please read the entire proposed rule

http://www.regulations.gov/#!docketDetail;D=APHIS-2007-0127

to review all the proposed changes as well as APHIS’ reasons for the proposed changes. Also, please read the draft “Scrapie Program Standards, Volume 1: National Scrapie Eradication Program” which is also posted at the link above. The rule proposes to:

1. Remove the low-risk commercial goat exemption and treat sheep and goats the same with respect to official identification requirements, the only differences are the allowed state exemptions which have not been changed.

2. Simplify the way the identification and movement requirements are presented and clarify the requirements. Also, adds tag replacement and use requirements from the ADT rule. Recommend reading proposed §79.2 and 79.3 in their entirety.

3. Add “Free” to “Scrapie Flock Certification Program” to read “Scrapie Free Flock Certification Program”

4. Change the noncompliant definition so that it now reads: Noncompliant flock. (1) Any source, infected, or exposed flock or flock under investigation whose owner declines to enter into a flock plan or post-exposure management and monitoring plan agreement within 30 days of being so designated, or whose owner is not in compliance with either agreement;

(2) Any exposed flock or flock under investigation whose owner fails to make animals available for testing within 60 days of notification, or as mutually agreed, or whose owner fails to submit required postmortem samples;

(3) Any flock whose owner has misrepresented, or who employs a person who has misrepresented, the scrapie status of an animal or any other information on a certificate, permit, owner statement, or other official document within the last 5 years; or

(4) Any flock whose owner or manager has moved, or who employs a person who has moved, an animal in violation of this chapter within the last 5 years.

5. Remove concept of “separate contemporary lambing group”.

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6. Change certificate to Interstate Certificate of Veterinary Inspection (ICVI). See proposed § 79.5 for ICVI requirements. Adds requirement for breeding animals that official genotype be included on the ICVI if known.

7. Change definition of flock sire to read: Flock sire. A sexually intact male animal that has produced offspring in the preceding 12 months or that was used for breeding during the current breeding cycle.

8. Change definition of scrapie positive animal to add ELISA Scrapie-positive animal. An animal for which a diagnosis of scrapie has been made by the National Veterinary Services Laboratories or another laboratory authorized by the Administrator to conduct scrapie tests in accordance with this chapter, through:

(1) Histopathological examination of central nervous system (CNS) tissues from the animal for characteristic microscopic lesions of scrapie;

(2) The use of proteinase-resistant protein analysis methods including but not limited to immunohistochemistry, and/or ELISA, and/or western blotting on CNS and/or peripheral tissue samples from a live or a dead animal for which a given method or combination of methods has been approved by the Administrator for use on that tissue;

(3) Bioassay;

(4) Scrapie associated fibrils (SAF) detected by electron microscopy; or

(5) Any other test method approved by the Administrator in accordance with §54.10 of this chapter.

9. Add the concept of “classification or reclassification investigation” and moves details for conducting them to the APHIS website in the program standards. See proposed § 79.4 and the draft program standards for more information.

Classification or reclassification investigation. An epidemiological investigation conducted or directed by a DSE for the purpose of designating or redesignating the status of a flock or animal. In conducting such an investigation, the DSE will evaluate the available records for flocks and individual animals and conduct or direct any testing needed to assess the status of a flock or animal. The status of an animal or flock will be determined based on the applicable definitions in this section and, when needed to make a designation under § 79.4 of this chapter, official genotype test results, exposure risk, scrapie type involved, and/or results of official scrapie testing on live or dead animals

10. Changes definition of destroy, removes slaughter option for indemnified animals

Destroyed. Euthanized and the carcass disposed of by means authorized by the Administrator that will prevent its use as feed or food,

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or moved to a quarantined research facility if the movement has been approved by the Administrator.

11. Change exposed animal definition:

a. Adds embryo explicitly

b. Sets criteria for setting date of infection

c. Adds concept of further designation based on genotype and exposure risk.

Exposed animal. Any animal or embryo that: (1) Has been in a flock or in an enclosure off the premises of the flock with a scrapie-positive female animal, (2) resides in a noncompliant flock, or (3) has resided on the premises of a flock before or while it was designated an infected or source flock and before a flock plan was completed. An animal shall not be designated an exposed animal if it only resided on the premises before the date that infection was most likely introduced to the premises as determined by a Federal or State representative. If the probable date of infection cannot be determined based on the epidemiologic investigation, a date 2 years before the birth of the oldest scrapie-positive animal(s) will be used. If the actual birth date is unknown, the date of birth will be estimated based on examination of the teeth and any available records. If an age estimate cannot be made, the animal will be assumed to have been 48 months of age on the date samples were collected for scrapie diagnosis. Exposed animals will be further designated as genetically resistant exposed sheep, genetically less susceptible exposed sheep, genetically susceptible exposed animals, or low-risk exposed animals. An animal will no longer be an exposed animal if it is redesignated in accordance with § 79.4.

12. Redefine exposed flock (divides old definition into Flock Under Investigation and Exposed Flock and references redesignation section: Exposed flock. (1) Any flock that was designated an infected or source flock that has completed a flock plan and that retained a female genetically susceptible exposed animal; (2) Any flock under investigation that retains a female genetically susceptible exposed animal or a suspect animal, or whose owner declines to complete genotyping and live-animal and/or post-mortem scrapie testing required by the APHIS or State representative investigating the flock; or (3) Any noncompliant flock or any flock for which a PEMMP is required that is not in compliance with the conditions of the PEMMP. A flock will no longer be an exposed flock if it is redesignated in accordance with § 79.4 of this chapter.

Flock under investigation. Any flock in which an APHIS or State representative has determined that a scrapie-suspect animal, high-risk animal, or scrapie-positive animal resides or may have resided. A flock will no longer be a flock under investigation if it is redesignated in accordance with § 79.4 of this chapter.

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13. Add definitions for genetically less susceptible exposed sheep, genetically resistant exposed sheep, genetically resistant sheep, genetically susceptible animal, and genetically susceptible exposed animal.

Genetically less susceptible exposed sheep. Any sheep or sheep embryo that is:

(1) An exposed sheep or sheep embryo of genotype AA QR, unless it is epidemiologically linked to a scrapie-positive RR or AA QR sheep or to a scrapie type to which AA QR sheep are not less susceptible where Q represents any genotype other than R at codon 171; or

(2) An exposed sheep or sheep embryo of genotype AV QR, unless it is epidemiologically linked to a scrapie-positive RR or QR sheep, to a flock that the DSE has determined may be affected by valine associated scrapie (based on an evaluation of the genotypes of the scrapie-positive animals linked to the flock), or to another scrapie type to which AV QR sheep are not less susceptible where Q represents any genotype other than R at codon 171 and V represents any genotype other than A at codon 136; or

(3) An exposed sheep or sheep embryo of a genotype that has been exposed to a scrapie type to which the Administrator has determined that genotype is less susceptible.

Genetically resistant exposed sheep. Any exposed sheep or sheep embryo of genotype RR unless it is epidemiologically linked to a scrapie-positive RR sheep or to a scrapie type to which RR sheep are not resistant.

Genetically resistant sheep. Any sheep or sheep embryo of genotype RR unless it is epidemiologically linked to a scrapie-positive RR sheep or to a scrapie type that affects RR sheep.

Genetically susceptible animal. Any goat or goat embryo, sheep or sheep embryo of a genotype other than RR or QR, or sheep or sheep embryo of undetermined genotype where Q represents any genotype other than R at codon 171.

Genetically susceptible exposed animal. Excluding low-risk exposed animals, any exposed animal or embryo that is also: (1) A genetically susceptible animal.

(2) A sheep or sheep embryo of genotype AV QR that is epidemiologically linked to a scrapie-positive RR or QR sheep, to a flock that the DSE has determined may be affected by valine associated scrapie (based on an evaluation of the genotypes of the scrapie-positive animals linked to the flock), or to a scrapie type to which AV QR sheep are susceptible where Q represents any genotype other than R at codon 171 and V represents any genotype other than A at codon 136.

(3) A sheep or sheep embryo of genotype AA QR that is epidemiologically linked to a scrapie-positive RR or AA QR sheep or to

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a scrapie type to which AA QR sheep are susceptible where Q represents any genotype other than R at codon 171; or

(4) A sheep or sheep embryo of genotype RR that is epidemiologically linked to a scrapie-positive RR sheep or to a scrapie type to which RR sheep are susceptible.

14. High-risk animal redefined as. The female offspring or embryo of a scrapie-positive female animal, or any suspect animal, or a female genetically susceptible exposed animal, or any exposed animal that the Administrator determines to be a potential risk based on the scrapie type, the epidemiology of the flock or flocks with which it is epidemiologically linked, including genetics of the positive sheep, the prevalence of scrapie in the flock, any history of recurrent infection, and other flock characteristics. An animal will no longer be a high-risk animal if it is redesignated in accordance with § 79.4 of this chapter. This in concert with the new low-risk exposed animal definition below gives a lot of flexibility in handling infected/source flocks and exposed animals minimizing the need to revise the regulations as scientific knowledge increases. It also allows APHIS to not restrict animals exposed to Nor98-like scrapie and to at some point if warranted by new scientific evidence establish a genetic based approach for goats. Low-risk exposed animal. Any exposed animal to which the DSE has determined one or more of the following applies:

(1) The positive animal that was the source of exposure was not born in the flock and did not lamb in the flock or in an enclosure where the exposed animal resided;

(2) The Administrator and State representative concur that the animal is unlikely to be infected due to factors such as, but not limited to, where the animal resided or the time period the animal resided in the flock;

(3) The exposed animal is male and was not born in an infected or source flock;

(4) The exposed animal is a castrated male;

(5) The exposed animal is an embryo of a genetically resistant exposed sheep or a genetically less susceptible exposed sheep unless placed in a recipient that was a genetically susceptible exposed animal; or,

(6) The animal was exposed to a scrapie type and/or is of a genotype that the Administrator has determined poses low risk of scrapie transmission.

15. Change the first paragraph of the suspect animal definition to read:

(1) A mature sheep or goat as evidenced by eruption of the first incisor that has been condemned by FSIS or a State inspection authority for central nervous system (CNS) signs, or that exhibits any of the following clinical signs of scrapie and has been determined to be suspicious for scrapie by an accredited veterinarian or a State or USDA representative, based on one or more of the following signs and

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the severity of the signs: (i) Weakness of any kind including, but not limited to, stumbling, falling down, or having difficulty rising, not including those with visible traumatic injuries and no other signs of scrapie; (ii) behavioral abnormalities; (iii) significant weight loss despite retention of appetite or in an animal with adequate dentition; (iv) increased sensitivity to noise and sudden movement; (v) tremors; (vi) star gazing; (vii) head pressing; (viii) bilateral gait abnormalities such as but not limited to incoordination, ataxia, high stepping gait of forelimbs, bunny-hop movement of rear legs, or swaying of back end, but not including abnormalities involving only one leg or one front and one back leg; (ix) repeated intense rubbing with bare areas or damaged wool in similar locations on both sides of the animal’s body or, if on the head, both sides of the poll; (x) abraded, rough, thickened, or hyperpigmented areas of skin in areas of wool/hair loss in similar locations on both sides of the animal’s body or, if on the head, both sides of the poll; or (xi) other signs of CNS disease. An animal will no longer be a suspect animal if it is redesignated in accordance with §

79.4 of this chapter.

16. Add definition of tamper-resistant sampling kit and changes definition of Official genotype test to allow sampling using an APHIS approved tamper evident eartag for official genotyping. Note: APHIS is not aware of tamper-evident versions of these devices being commercially available.

17. Add definition of owner/hauler statement in place of previous owner statement.

Owner/hauler statement. A signed written statement by the owner or hauler that includes:

(1) The name, address, and phone number of the owner and, if different, the hauler;

(2) The date the animals were moved;

(3) The flock identification number or PIN assigned to the flock or premises of the animals;

(4) If moving individually unidentified animals, the group/lot identification number and any information required to officially identify the animals;

(5) The number of animals;

(6) The species, breed, and class of animals. If breed is unknown, for sheep the face color and for goats the type (milk, fiber, or meat) must be recorded instead; and

(7) The name and address of point of origin, if different from the owner’s address, and the destination.

18. Add definition:

Restricted animal sale or restricted livestock facility. A sale where any animals in slaughter channels are maintained separate from other animals not in slaughter channels and are sold in lots that consist entirely of animals sold for slaughter only or a livestock facility at which

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all animals are in slaughter channels and where the sale or facility manager maintains a copy of, or maintains a record of, the information from, the owner/hauler statement for all animals entering and leaving the sale or facility. A restricted animal sale may be held at a livestock facility that is not restricted.

19. Tighten up slaughter channels through revised definition and requirement for an owner hauler statement and addition of §79.3(g).

Slaughter channels. Animals in slaughter channels include any animal that is sold, transferred, or moved either directly to or through a restricted animal sale or restricted livestock facility to a slaughter establishment that is under continuous inspection by the Food Safety and Inspection Service or under State inspection that the Food Safety and Inspection Service has recognized as at least equal to Federal inspection or to a custom exempt slaughter establishment as defined by FSIS for immediate slaughter or to an individual for immediate slaughter for personal use or to a terminal feedlot. Any animal sold at an unrestricted sale is not in slaughter channels. Animals in slaughter channels must be accompanied by an owner/hauler statement completed in accordance with § 79.3(g) of this chapter. Animals in slaughter channels may not be held in the same enclosure with sexually intact animals from another flock of origin that are not in slaughter channels. When selling animals that do not meet the requirements to move as breeding animals, owners must note on the bill of sale that the animals are sold only for slaughter.

79.3(g) Animals moved to slaughter. Once an animal enters slaughter channels the animal may not be removed from slaughter channels. An animal is in slaughter channels if it was sold through a restricted animal sale, resided in a terminal feedlot, was sold with a bill of sale marked for slaughter only, was identified with an identification device or tattoo marked “slaughter only” or “MEAT” or was moved in a manner not permitted for other classes of animals. Animals in slaughter channels may move either directly to a slaughter establishment that is under continuous inspection by the Food Safety and Inspection Service or under State inspection that the Food Safety and Inspection Service has recognized as at least equal to Federal inspection or to a custom exempt slaughter establishment as defined by FSIS for immediate slaughter or to an individual for immediate slaughter for personal use, to a terminal feedlot, or may move indirectly to such a destination through a restricted animal sale or restricted livestock facility. Once an animal has entered slaughter channels it may only be officially identified with an official blue eartag marked with the words “Meat” or “Slaughter Only" or an ear tattoo reading "Meat." Animals in slaughter channels must be accompanied by an owner/hauler statement indicating the owner’s name and address; the name and address of the person or livestock facility from which and where they were acquired, if different from the owner; the slaughter establishment,

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restricted animal sale, restricted livestock facility or terminal feedlot to which they are being moved, and a statement that the animals are in slaughter channels. A copy of the owner/hauler statement must be provided to the slaughter establishment, restricted animal sale, restricted livestock facility or terminal feedlot to which the animals are moved. Any bill of sale regarding the animals must indicate that the animals were sold for slaughter only.

20. Revises Terminal feedlot definition by revising paragraph 1 to include removal of organic material before use by other sheep or goats, by adding paragraph 2, and revising paragraph 3 (now 4) to increase the record retention requirement to 5 years and reiterate that the owner hauler statement or the information contained therein must be retained: Terminal feedlot. (1) A dry lot approved by a State or APHIS representative or an accredited veterinarian who is authorized to perform this function where animals in the terminal feedlot are separated from all other animals by at least 30 feet at all times or are separated by a solid wall through, over, or under which fluids cannot pass and contact cannot occur and must be cleaned of all organic material prior to being used to contain sheep or goats that are not in slaughter channels, where only castrated males are maintained with female animals and from which animals are moved only to another terminal feedlot or directly to slaughter; or

(2) A dry lot approved by a State or APHIS representative or an accredited veterinarian authorized to perform this function where only animals that either are not pregnant based on the animal being male, an owner certification that any female animals have not been exposed to a male in the preceding 6 months, an ICVI issued by an accredited veterinarian stating the animals are open, or the animals are under 6 months of age at time of receipt, where only castrated males are maintained with female animals, and all animals in the terminal feedlot are separated from all other animals such that physical contact cannot occur and from which animals are moved only to another terminal feedlot or directly to slaughter; or

(3) A pasture when approved by and maintained under the supervision of the State and in which only nonpregnant animals are permitted based on the animal being male, an owner certification that any female animals have not been exposed to a male in the preceding 6 months, or an ICVI issued by an accredited veterinarian stating the animals are open, or the animals are under 6 months of age at time of receipt, where only castrated males are maintained with female animals, where there is no direct fence-to-fence contact with another flock, and from which animals are moved only to another terminal feedlot or directly to slaughter.

(4) Records of all animals entering and leaving a terminal feedlot must be maintained for 5 years after the animal leaves the feedlot and must meet the requirements of § 79.2 of this chapter,

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including either a copy of the required owner/hauler statements for animals entering and leaving the facility or the information required to be on the statements. Records must be made available for inspection and copying by an APHIS or State representative upon request.

21. In the indemnity sections proposed § 54.3 adds:

a. Prohibitions:

No indemnity will be paid for any animal, or the progeny of any animal, that has been moved or handled by the owner in violation of the requirements of the Animal Health Protection Act or the regulations promulgated thereunder. No indemnity will be paid for an animal added to the premises while a flock is under investigation or while it is an infected or source flock other than natural additions. No indemnity will be paid for natural additions born more than 60 days after the owner is notified they are eligible for indemnity unless the Administrator makes a determination that the dam could not be removed within the allowed time as a result of conditions outside the control of the owner. No indemnity will be paid unless the owner has signed and is in compliance with the requirements of a flock plan or PEMMP as described in § 54.8.

b. Allows partial indemnity if cleaning and disinfection cannot be completed due weather or other factors outside the control of the owner make immediate disinfection impractical.

c. Moves specific instructions for calculating indemnity to the program standards which includes specific language on late gestation and early lambing premiums as well as allows for the use of available price reports rather than specifying particular ones, which may become unavailable. See proposed § 54.6 and draft program standards for details.

22. Add language stating that APHIS may pay full disposal costs for indemnified animals

23. Add use of an EPA approved product should one be approved or new exempted products

24. Update section § 54.8 Requirements for flocks under investigation and flocks subject to flock plans and post-exposure management and monitoring plans (PEMMPs)

a. Reorganized and reworded for clarity

b. Adds flocks under investigation to the requirements for official identification

c. Requires official identification on all animals in a flock under a flock plan or PEMMP

d. Specifically allows APHIS to establish policies for retention of high-risk animals.

e. Gives more flexibility on when a PEMMP will be used

25. Update section § 54.10 Program approval of tests for scrapie

a. Adds information on appeals

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b. Moves test use guidelines to the APHIS website. See draft program standards for details.

26. Update section § 54.11 Approval of laboratories to run official scrapie tests and official genotype tests

a. Adds ability for NVSL to waive tissue retention times in an SOP

b. Adds additional information on appeals

c. Adds that NVSL may recoup costs associated with laboratory approval from the approved laboratories

27. Change low-risk commercial sheep to low-risk commercial flock to include goats, but limits this exception to animals moving for slaughter

28. Require submission of tagging records by individuals who tag animals for others such as markets and veterinarians through a website or by other mutually agreed methods.

29. Revise information required to be maintained about animal dispositions/acquisitions and records of animals tagged. Remove requirement to record tags that are on animals when acquired unless an ICVI is required.

30. Add meeting surveillance targets as a requirement for remaining a consistent state and requires States to conduct of facilitate surveillance in State inspected mature sheep and goat slaughter establishments (see proposed § 79.6).

31. Simplify the requirements for inconsistent states and includes the option to use genotyping for movement of breeding sheep in addition to enrollment in SFCP (see proposed § 79.3(j)).

32. Move the Consistent State List to the website in the program standards and provides for notice and comment for changing the list. Specifically, the definition is changed to read:

Consistent State. (1) A State that the Administrator has determined conducts an active State scrapie control program that meets the requirements of §79.6 or effectively enforces a State-designed plan that the Administrator determines is at least as effective in controlling scrapie as the requirements of § 79.6.

(2) A list of Consistent States can be found on the Internet at http://www.aphis.usda.gov/animal-health/scrapie.

(3) When the Administrator determines that a State should be added to or removed from the list of Consistent States, APHIS will publish a notice in the Federal Register advising the public of the Administrator's determination, providing the reasons for that determination, and soliciting public comments. After considering any comments we receive, APHIS will publish a second notice either advising the public that the Administrator has decided to add or remove the State from the list of Consistent States or notifying the public that the Administrator has decided not to make any changes to the list of Consistent States, depending on the information presented in the comments.

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33. Add/revise definitions for flock identification (ID) number, Premises identification number (PIN) and group/lot number

Flock identification (ID) number. A nationally unique number assigned by a State or Federal animal health authority to a group of animals that are managed as a unit on one or more premises and are under the same ownership. The flock ID number must begin with the State postal abbreviation, must have no more than nine alphanumeric characters, and must not contain the characters “I”, “O”, or "Q" other than as part of the State postal abbreviation or another standardized format authorized by the administrator and issued through the National Scrapie Database. Flock identification numbers will be linked in the National Scrapie Database to one or more PINs and may be used in conjunction with an animal number unique within the flock to provide a unique official identification number for an animal, or may be used in conjunction with the date and a sequence number to provide a GIN for a group of animals when group identification is permitted.

Premises identification number (PIN). This term has the meaning set forth in § 86.1 of this subchapter. APHIS may also maintain historical and/or State premises numbers and link them to the premises identification number in records and databases. Such secondary or historical numbers are typically the State's two-letter postal abbreviation followed by a number assigned by the State.

Group/lot identification number (GIN). The identification number used to uniquely identify a unit of animals that is managed together as one group. The format of the GIN may be either as defined in § 71.1 of this chapter, or the flock identification number followed by a six-digit representation of the date on which the group or lot of animals was assembled (MM/DD/YY). If more than one group is created on the same date a sequential number will be added to the end of the GIN. If a flock identification number is used, the flock identification number, date, and sequential number will be separated by hyphens.

34. Revise definitions of Animal identification number (AIN), Officially identified, Official identification device or method and Official Eartag for clarity to specific the use of devices approved and distributed in accordance the scrapie rules and methods approved for use in sheep and goats by APHIS.

35. Explicitly allows an appeal of designation decisions see proposed § 79.4(c)(3). Draft rules of practice may be found in the draft program standards.

Prohibit transferring official eartags without the permission of APHIS or the State or applying official sheep and goat tags to animals other than sheep or goats. See proposed § 79.2 (b)(5)(d&e)

36. Does not allow use of back tags as official ID.

37. Provide for eartagging compliance agreements. See proposed § 79.3 (k).

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38. Allow APHIS through the program standards or other web posting to establish the requirements for official identification devices and methods including:

a. Establishing allowed colors and limiting certain colors to certain uses. For example only “slaughter only” official sheep and goat eartags can be blue and all “slaughter only” official sheep and goat eartags must be blue. Specifies that yellow metal official tags will be used for permanently exposed animals and that red metal official tags will be used for animals that have tested positive for scrapie.

b. Requirements for use of tattoos. Proposed changes:

i. Not allowed as a sole means of official identification on animals in slaughter channels or moving through livestock markets

ii. Registry tattoos must be issued by a registry that has agreed to cooperate with APHIS in tracing scrapie positive and exposed animals or the registry tattoo prefix must be provide to APHIS for entry into the National Scrapie Database.

c. Requirements for use of electronic implants. Proposed changes:

i. Not allowed as a sole means of official identification on animals in slaughter channels or moving through livestock markets

ii. If used as the sole form of official identification must be tattooed with “E” for implants in the ear or “ET” for implants in the tail

iii. If used in an unregistered animal must also be tattooed with the flock identification number.

d. Specifies that eartags must be placed in the ear.

See the draft program standards (link) or the extract of materials (link) referred to in the proposed rule available on the web for more detailed information.

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Specialist Commission Reports

A. Scientific Commission for Animal Diseases (SCAD) – The SCAD addresses technical issues, and makes science based recommendations to the Terrestrial Animal Health Standards (Code) Commission for improving and updating the various Code Chapters. The President of the SCAD summarized the activities of the Commission during the previous year. These included:

a. Overseeing and directing the work of 21 different expert ad hoc groups;

b. Amending and finalizing the chapters on:

 snip...

 Bovine spongiform encephalopathy (BSE), making a clear distinction between classical and atypical BSE, and clarifying that it is only the classical form for which status is granted, and that findings of atypical BSE do not affect status;

snip...

241

s. Bovine Spongiform Encephalopathy (Chapter 11.4) – this chapter was updated to recognize the distinction between “classical BSE” and “atypical BSE.” New Zealand, on behalf of the Quads countries (New Zealand, Australia, United States, and Canada), made an intervention. Specifically, the Quads are concerned that once again changes to a current Terrestrial Animal Health Code chapter are being proposed for adoption without Member Countries being given the appropriate opportunity to consider the changes carefully and offer comment to the Terrestrial Animal Health Standards Commission. While acknowledging that there may be occasions when changes to Code chapters must be made with urgency, this was not such an occasion. The Quads recognized the need to make a distinction between the occurrence of a case of “classical” BSE and a case of “atypical” BSE, and welcomed the recognition that a case of “atypical” BSE, an uncommon, spontaneously occurring condition, should not negatively affect a country’s BSE risk status. However, the changes proposed have broader implications. With the normal cycle of Member Country comments on proposed changes, countries would have time to recognise the implications for surveillance and information gathering systems and be prepared when the changes are adopted after the normal process of consultation and comment. The Quads also pointed to another problem with rushing this revised text through. A very important distinction is made between “classical” and “atypical” BSE. However, nowhere in the Code or Manual is there a case definition for either condition. Before the Code recommends different responses to these two conditions, the OIE Member Countries should be provided with definitive case

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definitions so as to avoid ambiguity and dispute over BSE status. Since the occurrence of “atypical” BSE has been recognised for several years now, the Quads suggested that there was no need for urgency to make changes to the Code and the normal cycle of Member Countries’ scrutiny, comment and consultation should be followed. The EU, however, did have an urgency to get these changes through (likely because they have been detecting “atypical” cases of BSE and did not want these to influence their status, since the Code does not currently make such a distinction). A compromise was reached by not adopting the proposed changes, but adding a short sentence at the end of the introductory paragraph of the chapter which reads: “For the purpose of official BSE status recognition, BSE excludes ‘atypical BSE’ as it is a condition believed to occur spontaneously in all cattle populations at a very low rate.” Countries can now review the proposed changes and submit any comments before the next meeting of the Code Commission in September 2015.

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http://www.usaha.org/Portals/6/Proceedings/2015%20Proceedings%20web2.pdf

Sunday, October 25, 2015

USAHA Detailed Events Schedule – 119th USAHA Annual Meeting CAPTIVE LIVESTOCK CWD SCRAPIE TSE PRION

https://www.researchgate.net/publication/306395646_PROCEEDINGS_ONE_HUNDRED_AND_Nineteenth_ANNUAL_MEETING_of_the_UNITED_STATES_ANIMAL_HEALTH_ASSOCIATION_BSE_CWD_SCRAPIE_PORCINE_TSE_Prion_Rhode_Island_Convention_Center_Providence_Rhode_Island_October_22

http://chronic-wasting-disease.blogspot.com/2015/10/usaha-detailed-events-schedule-119th.html

https://chronic-wasting-disease.blogspot.com/2016/08/proceedings-one-hundred-and-nineteenth.html

***> 2026 Chronic Wasting Disease CWD TSE PrP <***

Trying to GMO CWD out of Cervid, putting the cart before the horse, what could go wrong$

“These results indicate that the PRNP polymorphism modulates disease progression but does not prevent infection. Natural isolates also showed biochemical and pathological diversity, demonstrating the existence of diverse prion strains circulating in the environment.”

CWD prion strain variation modeled in the lab and identified in natural cases

SOTO, PAULINA 1Benavente, Maria 2Kramm, Carlos 2Stimming, Tucker 2Bravo-Risi, Francisca 3Pritzkow, Sandra 2Lyon, Adam 2Reed, J Hunter 4Soto, Claudio 2Morales, Rodrigo 5 Vol 1, 2025 - 328841 Abstract Prion 2025

Abstract Introduction: Chronic Wasting Disease (CWD) is a prion disease affecting cervids. It is characterized by distinct prion strains, which can influence transmission rates and disease phenotypes. In white-tailed deer, polymorphism at codon 96 of the PRNP gene (glycine (G) or serine (S)) is associated with differential susceptibility to CWD. The 96SS genotype has been consider “protective”; however, the potential for prion adaptation across deer PrP polymorphic variants remains unclear. Worrisomely, current surveillance strategies do not consider the identification of CWD prion strains, a fact that may contribute to CWD epidemiology.

Methods: We modeled inter-polymorphic prion conversion and demonstrate that prions can efficiently adapt in 96SS hosts with infectious properties like those in classical CWD strains. To investigate this, CWD prions from 96GG and 96SS deer were propagated by PMCA using homologous and heterologous transgenic brain homogenates, resulting in four strain combinations: GG/GG, SS/GG, GG/SS, and SS/SS (donor/recipient). These were characterized biochemically and tested in Tg1536and Tg60 mice. As part of this project, four natural CWD prion isolates identified in screening/diagnostic practices were similarly analyzed.

Results and Discussion: All experimental strains showed biochemical differences, indicating structural divergence. In Tg1536 mice, all strains produced disease with full attack rates. In Tg60mice, few animals developed clinical signs, but all showed PrPSc and vacuolation. These results indicate that the PRNP polymorphism modulates disease progression but does not prevent infection. Natural isolates also showed biochemical and pathological diversity, demonstrating the existence of diverse prion strains circulating in the environment.

PRION 2025 RIO DE JANEIRO

“ These new macaque studies confirmed that scrapie can be transmitted from certain sheep isolates to non-human primate after extended incubation periods (10 years), whereas after passage in Tg110 mice transmission may occur with two-fold shorter incubation periods.”

https://proceedings.science/prion-2025/papers?prod_proceedings_papers%5BrefinementList%5D%5Btrack.title.en%5D%5B0%5D=Animal%20prion%20diseases

https://proceedings.science/prion-2025/papers?prod_proceedings_papers%5BrefinementList%5D%5Bkeywords.en%5D%5B0%5D=Scrapie

https://proceedings.science/prion-2025/papers

https://proceedings.science/prion-2025?prod_proceedings_papers%5BrefinementList%5D%5Bkeywords.en%5D%5B0%5D=PMCA

Oklahoma decides to Play CWD TSE Prion Poker, and no one wins in Prion poker, with a experiment with Oklahomas wild deer herd and release GMO deer, what could go wrong, right? it’s like putting the cart before the horse science. these GMO deer are supposedly to be resistant to CWD, however, no deer has ever been confirmed to be totally resistant to CWD, and in fact, genotypes developed with very long incubation, could therefore, if released into the wild, could help spread cwd even further, exposing even more wild species, and surrounding environments, for even longer periods of time, due to the longer incubation, a terrible potential outcome, one that must be avoided at all cost, imo…terry

SCIENTISTS: RELEASING CAPTIVE-BRED DEER TO FIGHT CWD IN WILD DEER IS UNLIKELY TO WORK

October 1, 2025 By: Lindsay Thomas Jr.

Recently scientists have been exploring the idea that we can fight chronic wasting disease in wild deer by releasing captive-bred, “CWD resistant” deer. Some in the deer farming industry endorsed the idea, and legislators in Oklahoma even authorized a program to begin breeding and releasing deer. Most scientists, however, are urging everyone to pump the brakes.

On July 15, the Theodore Roosevelt Conservation Partnership invited two CWD experts to give a live webinar on the topic, titled “Breeding to Battle CWD: Can Wildlife Evolve Their Way Out of Disease?” To help shed more light on this important topic, this article is a summary of the most important take-home messages for deer hunters that came out of the two presentations. You can also watch the full presentations here.

https://www.trcp.org/chronic-wasting-disease/

PART 1: DR. DEBBIE MCKENZIE

The first speaker was Dr. Debbie McKenzie, an emeritus professor at the University of Alberta’s Centre for Prions and Protein Folding Diseases. Her research focus for the past 35 years has been on prion diseases, specifically CWD.

https://www.ualberta.ca/en/prion-centre/index.html

“Resistance” Needs More Evidence

This entire discussion originated with one study that suggested certain genetic strains of deer – known as the 96SS genotype – could be “resistant” to CWD. That study is a statistical model that suggests 96SS deer test positive for CWD less often than other deer. The study did not challenge live deer with CWD infection. Both speakers suggested they’d welcome the use of Genomically Estimated Breeding Value (GEBV) if it can slow the spread of CWD among captive herds, but they say real-world evidence is lacking so far.

“Though I think there’s some utility with GEBV, I really think we need some challenge experiments so we can demonstrate that these statistical analyses do point to increased resistance,” said Dr. McKenzie.

“Resistant” Deer Still Get CWD But Live Longer

Meanwhile, studies of actual deer, according to Dr. McKenzie, show that 96SS deer are not “resistant” but experience a longer incubation period before dying. “96SS and other polymorphisms are linked to slower disease progression, but they are not resistance genes,” she said. “If those animals are exposed, they will get CWD. It’s just going to take longer from the time they are infected until they are clinically sick.”

This chart from Dr. McKenzie’s presentation shows that some genotypes of deer survive longer than others with CWD but are not “resistant” because they can still acquire the disease. Living Longer With CWD Means Greater Spread

Longer incubation periods with CWD are counterproductive, because even CWD-infected 96SS deer are still shedding prions into the environment and sharing them with other deer. “Shedding is still occurring throughout those longer incubation periods,” said Dr. McKenzie. “If you have double the incubation period, but you’ve only made a 10% reduction in the prion shedding, you’re actually going to end up with more environmental contamination.”

New Strains Might Make “Resistant Deer” Irrelevant

New strains of CWD have already evolved, and more are coming. According to Dr. McKenzie, selecting for 96SS genetics in deer could theoretically lead to reduced susceptibility to some CWD strains. “On the other hand,” she said, “it might mean we’re selecting for susceptibility to a different strain.”

PART 2: DR. SONJA CHRISTENSEN

The second talk by Dr. Sonja Christensen took the science into the real world to look at the likelihood of using genetically resistant deer – assuming they are found to be a real thing – to fight CWD in wild deer populations. Dr. Christensen is an assistant professor at Michigan State University who specializes in wildlife disease ecology, population health, and wildlife management.

http://www.christensen-lab.org/

Wild Deer Are a Different Issue Than Captive Deer

Genetic resistance to CWD could have usefulness in captive deer, where people control which deer do the breeding. “However, I am focused solely on wild deer,” said Dr. Christensen. “Wild populations are inherently messy.”

We Can’t Manage Genetics in Wild Deer

Hunters have mistakenly believed for years that they can change the genetics of future deer through selective harvest, but repeated scientific experiments have failed to show that it’s possible to make a measurable difference – even under very intensive manipulation of deer harvest. The reasons why also explain why releasing a few “CWD resistant” deer in an area would be unlikely to have any impact on wild deer genetics.

https://deerassociation.com/strike-3-for-the-myth-of-the-genetic-cull-buck/

Dr. Christensen listed several of the factors that would complicate any kind of genetic fight against CWD in wild deer. For example, there are over 30 subspecies of whitetails with genetic variations across regions. We lack the ability to control which deer do the breeding. Any genetically modified deer released into the wild might never reproduce due to being killed by predators, other diseases, and other mortality sources beyond our control.

Existing Native Deer Prevent Success

Stocking genetically modified deer could be more successful only if native deer with higher susceptibility to CWD are first removed. Dr. Christensen pointed out that fighting scrapie, a prion disease of sheep that is similar to CWD, required massive culling of sheep to increase resistance, and this was with captive livestock. Obviously, in the wild it would be nearly impossible to identify which deer are more susceptible or remove enough of them to make a difference.

It Would Take a Very, Very Long Time

“In the best case scenario, assuming everything’s working perfectly and we can control all of these factors in a very messy, free-ranging herd, it’s still going to take years and years and years and years to really see this change and pick up on that signal,” said Dr. Christensen.

Why Not Try It Anyway?

Despite all the evidence that stocking “resistant” deer would have no impact on CWD in wild deer populations, Dr. Christensen played devil’s advocate and asked, “Why not try it anyway?” She answered by highlighting the extreme costs and the unintended consequences.

“Captive deer genetics are not like wild deer genetics,” she said. “There might be other traits that are unknowingly entering a population when you release captive deer. Something else might be expressed. Because of the long incubation period, we could unknowingly release CWD-positive deer into an area that doesn’t have the disease. We could be increasing susceptibility to other diseases.”

“The outcome has a lot of uncertainly and cost for wildlife agencies, and that’s a risk to our natural resources that the wildlife agencies are managing in the public trust,” said Dr. Christensen. “Ultimately, that is undermining the North American Model of Wildlife Management and how wildlife management works.”

Other Comments About Release of Captive-Bred Deer to Fight CWD

The CWD Research Consortium, a group of independent researchers from diverse disciplines and institutions currently working on CWD, prepared a document to provide science-based information on the use of selective breeding and release of captive deer for CWD management.

https://www.cwd-research.com/home/selective-breeding-and-release-of-captive-white

The Association of Fish & Wildlife Agencies passed a resolution opposing “the release of any captive cervids into the wild to influence free-ranging cervid population genetics for the purpose of controlling or managing CWD, based on the current best scientific information, and encourages its members in their own jurisdictions to promote and implement the best scientific management practices for CWD.”

https://www.fishwildlife.org/landing/blog/state-fish-wildlife-agency-directors-pass-ten-resolutions-afwas-2024-annual-meeting

The United States Animal Health Association issued a resolution calling on the U.S. Department of Agriculture to conduct a controlled experiment to test the validity of CWD resistant genetics.

https://usaha.org/wp-content/uploads/2024/12/2024-USAHA-Resolutions-21.pdf

Categories: Deer Science Tags: Chronic Wasting Disease, Cwd

About Lindsay Thomas Jr.: Lindsay Thomas Jr. is NDA's Chief Communications Officer. He has been a member of the staff since 2003. Prior to that, Lindsay was an editor at a Georgia hunting and fishing news magazine for nine years. Throughout his career as an editor, he has written and published numerous articles on deer management and hunting. He earned his journalism degree at the University of Georgia.

https://deerassociation.com/scientists-releasing-captive-bred-deer-to-fight-cwd-in-wild-deer-is-unlikely-to-work/

Problem Statement 6B: Reveal genetics of prion disease susceptibility.

Greater frequency of chronic wasting disease in free-ranging elk genetically tolerant to disease progression raises concerns related to prion transmission and strain evolution.

Animal Disease Research Unit, Pullman, Washington

Genetic variations in the prion protein gene of Rocky Mountain elk do not confer complete resistance to fatal infection by chronic wasting disease. However, elk carrying one or two copies of the amino acid leucine (L) variant at position 132 of the prion protein (132L*, where * is either M for methionine or L) survive much longer than 132MM elk. An ARS researcher in Pullman, Washington, in collaboration with researchers at the University of Wyoming, the University of California at Davis, the National Park Service, and the Animal and Plant Health Inspection Service, found a higher frequency of 132L* elk in areas of Wyoming with high infection rates, consistent with the expected positive effect of prolonged survival on reproduction. However, the frequency of chronic wasting disease infection in 132L* elk was also higher than previous estimates. To improve the long-term management of native elk populations, these findings underscore the importance of determining the effects of prolonged infection on disease transmission from 132L* elk and the potential for driving prion strain diversification.

https://www.ars.usda.gov/ARSUserFiles/np103/AnnualReports/Final%20NP103%20FY2024%20Annual%20Report.updated%205.30.25.pdf

Research Project: Elucidating the Pathobiology and Transmission of Transmissible Spongiform Encephalopathies

Location: Virus and Prion Research Title: Update: CWD genetic resistance project at NADC Author item Cassmann, Eric item Greenlee, Justin Submitted to: North American Deer Farmer Publication Type: Trade Journal Publication Acceptance Date: 11/5/2023 Publication Date: 11/15/2023 Citation: Cassmann, E.D., Greenlee, J.J. 2023.

Update: CWD genetic resistance project at NADC. North American Deer Farmer. P. 83. Interpretive Summary: Technical Abstract: In March of 2020, we began a study to examine the susceptibility of whitetail deer with rare prion protein genotypes to chronic wasting disease (CWD). In the sequence of amino acids that make up the deer prion protein, there are several locations that are variable. These variations are sometimes called polymorphisms. In the data collected from depopulations, whitetail deer with certain prion gene polymorphisms were not positive for CWD. In 2019, Dr. Nick Haley published a paper that showed H95/S96, HH95, and S96/K226 deer from depopulated herds in the US were not CWD positive. Based on the overall low number of deer with these genotypes () we’re unable to determine if they were resistant to CWD or if there were too few deer with these genotypes to be statistically represented in the positive cases. It’s also possible that they could be partially susceptible with longer incubation times than deer with generic (wild type) prion genotypes. Samples gathered at depopulation represent a snapshot of the herd. It is possible these rare genotypes were exposed, but had not yet accumulated abnormal prion protein to a level detectable by the detection methods used. The NADC susceptibility study was initiated to help answer these questions.

We studied deer with polymorphisms at 3 amino acid locations (codons): 95, 96, and 226. Wild type deer are QQ95GG96QQ226. Whitetail deer with wild type prion genotypes were inoculated with CWD and co-housed with other whitetail deer (contact deer) that had rare prion protein genotypes. The genotypes of contact deer included QH95GS96QQ226, QH95GG96QK226, QQ95GS96QQ226, QQ95SS96QQ226, Q95GS96QK226, and QQ95GG96KK226 (bolded text indicates a prion gene polymorphism).

During the first year, we collected feces, saliva, nasal swabs, skin, blood, and rectal biopsies from the inoculated and contact deer to determine if deer are CWD positive and the period of CWD shedding. After the first year, we started collecting rectal biopsies annually on the contact deer, but all other samples are still collected every three months.

Eight out of ten (8/10) inoculated deer developed clinical signs for CWD and tested positive after necropsy (Figure 1). The average time from inoculation to euthanasia of these eight inoculated deer was 23 months.

Two inoculated deer are still on-study; one of these deer has tested positive for CWD on rectal biopsy IHC.

To date, two deer from the contact group have developed CWD clinical signs and tested positive (Figure 2). The positive deer from the contact group had the GS96QK226 and KK226 genotypes.

We have detected CWD prions in rectal biopsies with IHC in three other contact deer as of October 2023. Their prion genotypes are GS96, QH95GS96, and GS96QK226.

As the experiment continues, we hope to answer 2 main questions. (1) Are there any prion protein polymorphisms that make deer resistant to CWD, and (2) what are the CWD shedding dynamics in deer with detectable CWD. One potential outcome of the study would be identifying genotypes with very long incubation periods that, while susceptible to CWD, still could be used to manage CWD.

https://www.ars.usda.gov/research/publications/publication/?seqNo115=410188

Update: CWD genetic resistance project at NADC 1) Are there any prion protein polymorphisms that make deer resistant to CWD, and (2) what are the CWD shedding dynamics in deer with detectable CWD. One potential outcome of the study would be identifying genotypes with very long incubation periods that, while susceptible to CWD, still could be used to manage CWD.

https://www.ars.usda.gov/research/publications/publication/?seqNo115=410188

Another potential and likely outcome of this study, imo, is that genotypes developed with very long incubation, could therefore, if released into the wild, could help spread cwd even further, exposing even more wild species, and surrounding environments, for even longer periods of time, due to the longer incubation, a terrible potential outcome, one that must be avoided at all cost, imo…terry

LEGISLATING CWD TSE Prion, Bills to release Genetically Modified Cervid into the wild, what could go wrong?

“If slower disease progression results in longer-lived, infected deer with longer periods of infectiousness, resistance may lead to increased disease transmission rates, higher prion concentrations in the environment, and increased prevalence, as has been observed in some captive deer herds (Miller et al., 2006; Keane et al., 2008a).”

Genetic susceptibility to chronic wasting disease in free-ranging white-tailed deer: Complement component C1q and Prnp polymorphisms§

Julie A. Blanchong a, *, Dennis M. Heisey b , Kim T. Scribner c , Scot V. Libants d , Chad Johnson e , Judd M. Aiken e , Julia A. Langenberg f , Michael D. Samuel g

snip...

Identifying the genetic basis for heterogeneity in disease susceptibility or progression can improve our understanding of individual variation in disease susceptibility in both free-ranging and captive populations. What this individual variation in disease susceptibility means for the trajectory of disease in a population, however, is not straightforward. For example, the greater, but not complete, resistance to CWD in deer with at least one Serine (S) at amino acid 96 of the Prnp gene appears to be associated with slower progression of disease (e.g., Johnson et al., 2006; Keane et al., 2008a). If slower disease progression results in longer-lived, infected deer with longer periods of infectiousness, resistance may lead to increased disease transmission rates, higher prion concentrations in the environment, and increased prevalence, as has been observed in some captive deer herds (Miller et al., 2006; Keane et al., 2008a). Alternatively, if the slower progression of disease in resistant deer is not associated with longer periods of infectiousness, but might instead indicate a higher dose of PrPCWD is required for infection, transmission rates in the population could decline especially if, as in Wisconsin, deer suffer high rates of mortality from other sources (e.g., hunting). Clearly, determining the relationship between genetic susceptibility to infection, dose requirements, disease progression, and the period of PrPCWD infectiousness are key components for understanding the consequences of CWD to free-ranging populations.

http://web.archive.org/web/20121114223603/http://forest.wisc.edu/files/pdfs/samuel/2009%20blanchong%20et%20al%20genetic%20susceptibility%20chronic%20wasting.pdf

https://dr.lib.iastate.edu/server/api/core/bitstreams/630cd976-0c33-4b0a-bc97-96e2669107d5/content

TEXAS CWD, WHILE IGNORING THE PROBLEM AT HAND, TRYING TO GMO YOUR WAY OUT SAID PROBLEM, TRYING TO LEGISLATING CWD, AND IN DOING SO, POTENTIALLY CREATING A BIGGER PROBLEM, WHAT IF?

WE call this TSE Prion Poker, are you all?

Volume 30, Number 10—October 2024

Research

Temporal Characterization of Prion Shedding in Secreta of White-Tailed Deer in Longitudinal Study of Chronic Wasting Disease, United States

Our findings suggest that deer expressing alternative PRNP polymorphisms might live longer and, although they shed fewer prions throughout CWD course, might over their extended lifespan increase CWD prions in the environment

https://wwwnc.cdc.gov/eid/article/30/10/24-0159_article

Prion protein gene sequence and chronic wasting disease susceptibility in white-tailed deer (Odocoileus virginianus)

Adam L Brandt, Amy C Kelly, Michelle L Green, Paul Shelton, Jan Novakofski & Nohra E Mateus-Pinilla

Pages 449-462 | Received 21 Sep 2015, Accepted 23 Oct 2015, Published online: 21 Dec 2015 https://doi.org/10.1080/19336896.2015.1115179

The presence of aa96S has been associated with slowed disease progression, longer life span among captive deer,Citation26,27 and does not appear to affect the rate at which prions are shed from infected individuals.Citation38 Additionally, CWD infected mule deer have been found to excrete pathogenic prions while asymptomatic.Citation39 This contributes to concerns that wild deer with aa96S may be shedding infectious prions into the environment for longer periods of time than deer lacking the mutation, but are not symptomatic or detectable by immunohistochemical procedures.

https://www.tandfonline.com/doi/full/10.1080/19336896.2015.1115179#d1e354

https://pmc.ncbi.nlm.nih.gov/articles/PMC4964855/pdf/kprn-09-06-1115179.pdf

''There are no known familial or genetic TSEs of animals, although polymorphisms in the PRNP gene of some species (sheep for example) may influence the length of the incubation period and occurrence of disease.''

c) The commonest form of CJD occurs as a sporadic disease, the cause of which is unknown, although genetic factors (particularly the codon 129 polymorphism in the prion protein gene (PRNP)) influence disease susceptibility. The familial forms of human TSEs (see Box 1) appear to have a solely genetic origin and are closely associated with mutations or insertions in the PRNP gene. Most, but not all, of the familial forms of human TSEs have been transmitted experimentally to animals. There are no known familial or genetic TSEs of animals, although polymorphisms in the PRNP gene of some species (sheep for example) may influence the length of the incubation period and occurrence of disease.

https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/209755/Part_1_-_Introduction.pdf

P-145 Estimating chronic wasting disease resistance in cervids using real time quaking- induced conversion

Nicholas J Haley1, Rachel Rielinqer2, Kristen A Davenport3, W. David Walter4, Katherine I O'Rourke5, Gordon Mitchell6, Juergen A Richt2 1

Our studies demonstrate that in vitro amplification metrics predict in vivo susceptibility, and that alleles with multiple codons, each influencing resistance independently, do not necessarily contribute additively to resistance. Importantly, we found that the white-tailed deer 226K substrate exhibited the slowest amplification rate among those evaluated, suggesting that further investigation of this allele and its resistance in vivo are warranted to determine if absolute resistance to CWD is possible. ***at present, no cervid PrP allele conferring absolute resistance to prion infection has been identified.

PRION 2016 CONFERENCE TOKYO

http://prion2016.org/dl/newsletter_03.pdf

http://chronic-wasting-disease.blogspot.com/2017/04/

***> at present, no PrPC allele conferring absolute resistance in cervids has been identified.

J Gen Virol. 2017 Nov; 98(11): 2882–2892.

Published online 2017 Oct 23. doi: 10.1099/jgv.0.000952

Estimating chronic wasting disease susceptibility in cervids using real-time quaking-induced conversion

Chronic wasting disease (CWD) resistance in cervids is often characterized as decreased prevalence and/or protracted disease progression in individuals with specific alleles; at present, no PrPC allele conferring absolute resistance in cervids has been identified.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5845664/pdf/jgv-98-2882.pdf

***> APHIS USDA Captive CWD Herds Update by State December 2025 Update <***

https://chronic-wasting-disease.blogspot.com/2025/12/aphis-usda-captive-cwd-herds-update-by.html

https://prpsc.proboards.com/thread/187/aphis-captive-herds-update-december

USDA EXPLANATORY NOTES ANIMAL AND PLANT HEALTH INSPECTION SERVICE 2025-2014 CHRONIC WASTING DISEASE CWD TSE CERVID

https://chronic-wasting-disease.blogspot.com/2025/09/usda-explanatory-notes-animal-and-plant.html

SUNDAY, MAY 04, 2025

Texas Senate Bill 2651 establishment of a pilot program to breed deer resistant to CWD TSE Prion, what could go wrong?

https://chronic-wasting-disease.blogspot.com/2025/05/texas-senate-bill-2651-establishment-of_4.html

FRIDAY, FEBRUARY 21, 2025

LEGISLATING CWD TSE Prion, Bills to release Genetically Modified Cervid into the wild, what could go wrong?

https://chronic-wasting-disease.blogspot.com/2025/02/legislating-cwd-tse-prion-bills-to.html

MONDAY, JUNE 09, 2025

Genetic Approaches and Tools to Prevent, Control, and Eradicate Transmissible Spongiform Encephalopathies 2024 Annual Report ARS Research

https://chronic-wasting-disease.blogspot.com/2025/06/genetic-approaches-and-tools-to-prevent.html

Oklahoma HB3462 Chronic Wasting Disease Genetic Improvement Act and Legislating CWD Science

Bill Summary 2nd Session of the 59th Legislature Bill No.: HB 3462 Version: CS Request No.: 3679 Author: Sen. Green Date: 04/08/2024 Bill Analysis

Greetings to the Great State of Oklahoma!

I must comment on the following please!

HB 3462 creates the Chronic Wasting Disease Genetic Improvement Act. The measure directs the Oklahoma Department of Agriculture, Food, and Forestry to establish a pilot program to enhance the genetic durability of Oklahoma deer against chronic wasting disease no later than November 1, 2024. The program shall require the Department of Wildlife Conservation to collect DNA samples to establish a baseline of average genetic codon markers and genomic breeding values. Participation in the program shall be limited to native white-tailed deer, born and raised in Oklahoma with genetic resistance breeding. Bred deer may be released in 2026, during the months of February and March and through the 15th of April. The Department of Wildlife Conservation may charge a one-time permit fee for citizens purchasing deer. The fee shall not exceed $500.00.

Prepared by: Kalen Taylor

http://webserver1.lsb.state.ok.us/cf_pdf/2023-24%20SUPPORT%20DOCUMENTS/BILLSUM/Senate/HB3462%20CS%20BILLSUM.PDF

Snip…see;

https://chronic-wasting-disease.blogspot.com/2024/05/oklahoma-hb3462-chronic-wasting-disease.html

USDA National Scrapie Program History and Bovine Spongiform Encephalopathy BSE TSE Update 2025 and history there from

https://www.researchgate.net/publication/396084947_USDA_National_Scrapie_Program_History_and_Bovine_Spongiform_Encephalopathy_BSE_TSE0AUpdate_2025

ARS Research Project: Elucidating the Pathobiology and Transmission of Transmissible Spongiform Encephalopathies 2025

“ARS researchers in Ames, Iowa, showed that white-tailed deer sick with scrapie from sheep can infect other deer under conditions mimicking natural exposure. Furthermore, this work shows that CWD is difficult to differentiate from WTD infected with scrapie. WTD scrapie prions accumulate in the lymphoreticular system in a manner similar to CWD, meaning that environmental contamination may occur through feces, saliva, and other body fluids of scrapie affected WTD as has been shown for CWD. The presence of WTD infected with scrapie could confound mitigation efforts for chronic wasting disease. This information informs regulatory officials, the farmed cervid industry, and officials tasked with protecting animal health such as state Departments of Agriculture, Natural Resources, or Parks and Wildlife with regard to a disease similar to CWD but arising from sheep scrapie that could be present in WTD that have contact with scrapie affected sheep and/or goats.”

Research Project: Elucidating the Pathobiology and Transmission of Transmissible Spongiform Encephalopathies

Location: Virus and Prion Research

2025 Annual Report

Objectives

Objective 1: Develop highly sensitive detection tools to determine the distribution of CWD and scrapie prions in natural hosts (sheep, goats, cervids) and their environment.

Objective 2: Investigate the pathobiology of CWD, scrapie prion strains, and atypical TSEs in natural hosts including potential cross species transmission events.

Objective 3: Investigate the genetics of CWD susceptibility and resistance in white-tailed deer.

Objective 4: Evaluate the presence of and determine the appropriate methodology for CWD strain determination.

Approach

Eradication or control of a family of diseases is unlikely or impossible when an understanding of the basic mechanisms and influences on transmission are unknown and for which methods to evaluate disease status are lacking. Scrapie and BSE represent the most thoroughly studied TSEs; however, significant knowledge gaps persist with regard to the atypical variants of these diseases. Further, much of the research emphasis to date on genetics of prion disease has focused on the recipient genotype rather than the source. Since both atypical BSE and atypical scrapie have been suggested to occur spontaneously, eradication of these diseases may not be possible unless we expand our understanding of the disease at both the source and recipient level. A better understanding of the tissue distribution and potential transmission of these atypical isolates is critical to understanding what risk these disease variants may pose to ongoing control and eradication efforts. The European epizootic of BSE is waning and efforts to eradicate scrapie in the U.S. and abroad have progressed but are not complete. In the U.S., chronic wasting disease (CWD) presents the most serious challenge to regulatory efforts. CWD appears to be spreading unchecked in both free-ranging and farmed cervids. Methods for antemortem detection of TSEs in general and CWD in particular are needed to fulfill the goal of eradicating scrapie and controlling CWD. Performing these studies will allow us to address critical knowledge gaps that are relevant to developing measures to restrict further disease expansion beyond current, affected populations. Understanding prion disease persistence in animal populations is challenging due to lack of tools for study and a less than complete understanding of transmission among animals within a flock or herd or in naturally occurring reservoirs. In addition to transmission between hosts of like species, free-ranging cervids may come in contact with numerous other species including cattle, sheep, and other susceptible hosts. Transmission of CWD to other species has been studied but limited with regard to the source genotype used. The four primary objectives are inherently linked. Our focus is on developing tools needed for control and research, and using those tools to advance our understanding the complex disease process with the overall goal of eradication and control of disease in livestock, wildlife of economic importance, and potential wildlife reservoirs.

Progress Report

The goals of the project plan for fiscal year (FY) 2025 consisted of 12 milestones, 11 of which were either fully or substantially met. The only milestone in this plan that was not met was due to insufficient animal availability and space constraints. Previous studies utilizing this space are not complete due to longer than anticipated incubation periods and cannot be initiated until those studies are complete. In work toward addressing

Objective 1, “Develop highly sensitive detection tools to determine the distribution of chronic wasting disease (CWD) and scrapie prions in natural hosts (sheep, goats, cervids) and their environment”, we have worked closely with ARS researchers in Pullman, Washington, Animal and Plant Health Inspection Service (APHIS), and university partners. The tools under development are directly utilized by state diagnostic labs and have been shared with the appropriate end users for evaluation. We have also assessed alternative dyes that have do not induce amyloid formation in the amplification based diagnostic assay known as RT-QuIC. While no increase in sensitivity was observed, differences between strains were found offering an additional means to differentiate strains for some TSEs.

Objective 2, “Investigate the pathobiology of CWD, scrapie prion strains, and atypical TSEs in natural hosts including potential cross species transmission events”, the studies in question have been initiated with the goal of furthering the understanding of these TSEs in agriculturally relevant species including the natural host species and other that may be exposed to these TSEs in an agricultural environment. The studies are ongoing and anticipated to last upwards of 5 year and observation of the animals is ongoing. No anticipated signs of disease or relevant reportable information have been seen nor are they expected until near the onset of clinical signs, but if they are observed they will be reported.

Objective 3, “Investigate the genetics of CWD susceptibility and resistance in white-tailed deer”, consists of two subobjectives:

A) Investigate the susceptibility of white-tailed deer to CWD modeling direct contact exposure with infected deer, and

B) Investigate the susceptibility of white-tailed deer to CWD after direct inoculation.

The first of these has been initiated on schedule while the second has been delayed considerably (greater than 3 years at this point) due to insufficient animal space.Upon completion these two studies will aid in understanding the disease and disease progression.

Objective 4, “Evaluate the presence of and determine the appropriate methodology for CWD strain determination”, is dependent upon obtaining a diverse set of CWD isolates. We are continuing the acquisition of these samples. . Strains are one of the least understood aspects of TSEs as a whole and of importance in understanding the risks of CWD. We have initiated studies that will address the biochemical nature of prion strains and how these strains are maintained in a host which will aid in addressing features and differentiation of strains as additional samples become available.

Accomplishments

1. 01 Determined that white-tailed deer (WTD) infected with scrapie from sheep can transmit the disease to other deer under conditions mimicking natural exposure. It has long been suggested that prion disease in deer (chronic wasting disease (CWD)) was caused by the prion agent from sheep. The prion disease that affects sheep, scrapie, has been recognized for hundreds of years. However, chronic wasting disease, a similar disease found in WTD, has only been recognized since the 1960s. ARS researchers in Ames, Iowa, showed that white-tailed deer sick with scrapie from sheep can infect other deer under conditions mimicking natural exposure. Furthermore, this work shows that CWD is difficult to differentiate from WTD infected with scrapie. WTD scrapie prions accumulate in the lymphoreticular system in a manner similar to CWD, meaning that environmental contamination may occur through feces, saliva, and other body fluids of scrapie affected WTD as has been shown for CWD. The presence of WTD infected with scrapie could confound mitigation efforts for chronic wasting disease. This information informs regulatory officials, the farmed cervid industry, and officials tasked with protecting animal health such as state Departments of Agriculture, Natural Resources, or Parks and Wildlife with regard to a disease similar to CWD but arising from sheep scrapie that could be present in WTD that have contact with scrapie affected sheep and/or goats.

2. 02 Showed that gene-targeted mice are capable of reproducing strain specific effects typically limited to natural host species of chronic wasting disease (CWD). CWD is a highly contagious disease of deer, elk, moose, and reindeer found in North America, South Korea, and Scandinavian countries that is caused by misfolded proteins called prions. CWD prions transmit through direct contact between infected animals, or through contaminated soil, grass, or water. All prion diseases exhibit progressive neurodegeneration and ultimately death. Scientists typically study CWD by injecting prions into susceptible animals' brains in lab experiments. Intracranial prion injections are favored because they typically produce shorter incubation periods and higher disease attack rates compared to natural infection. ARS researchers in Ames, Iowa, along with university collaborators showed that this inoculation method can cause the prion strains to change in a way that does not accurately reflect how the disease spreads naturally. They found that using a combination of peripheral inoculation (injection outside the brain) in natural hosts and using novel gene-targeted mice generated in a manner that provides a more natural expression of the inserted prion gene that gives a more accurate picture of how CWD behaves in the real world. The novel mouse model provides an important strategy to precisely assess the zoonotic potential (likelihood of transmission from animals to humans) of CWD and other animal prion diseases using natural routes of transmission. This will impact the tools used and direction of future studies of CWD and other prion diseases allowing more rapid and comprehensive responses to emerging questions aiding both the researchers at the producers they support…end

https://www.ars.usda.gov/research/project/?accnNo=440677&fy=202

ARS Research Elucidating the Pathobiology and Transmission of Transmissible Spongiform Encephalopathies 2025 Annual Report

CWD, transmission to, Cattle, Sheep, Pigs, Cervid, oh my!

Price of TSE Prion Poker Goes Up Again…terry

https://transmissiblespongiformencephalopathy.blogspot.com/2025/12/ars-research-elucidating-pathobiology.html

Chronic Wasting Disease CWD vs Scrapie TSE Prion

Volume 30, Number 8—August 2024

Research

Scrapie Versus Chronic Wasting Disease in White-Tailed Deer

Zoe J. Lambert1, Jifeng Bian, Eric D. Cassmann, M. Heather West Greenlee, and Justin J. Greenlee

Author affiliations: Oak Ridge Institute for Science and Education, Oak Ridge, Tennessee, USA (Z.J. Lambert); US Department of Agriculture, Ames, Iowa, USA (Z.J. Lambert, J. Bian, E.D. Cassmann, J.J. Greenlee); Iowa State University, Ames (Z.J. Lambert, M.H. West Greenlee) Suggested citation for this article

Abstract

White-tailed deer are susceptible to scrapie (WTD scrapie) after oronasal inoculation with the classical scrapie agent from sheep. Deer affected by WTD scrapie are difficult to differentiate from deer infected with chronic wasting disease (CWD). To assess the transmissibility of the WTD scrapie agent and tissue phenotypes when further passaged in white-tailed deer, we oronasally inoculated wild-type white-tailed deer with WTD scrapie agent. We found that WTD scrapie and CWD agents were generally similar, although some differences were noted. The greatest differences were seen in bioassays of cervidized mice that exhibited significantly longer survival periods when inoculated with WTD scrapie agent than those inoculated with CWD agent. Our findings establish that white-tailed deer are susceptible to WTD scrapie and that the presence of WTD scrapie agent in the lymphoreticular system suggests the handling of suspected cases should be consistent with current CWD guidelines because environmental shedding may occur.

snip…

The potential for zoonoses of cervid-derived PrPSc is still not well understood (6,18,45–47); however, interspecies transmission can increase host range and zoonotic potential (48–50). Therefore, to protect herds and the food supply, suspected cases of WTD scrapie should be handled the same as cases of CWD.

https://wwwnc.cdc.gov/eid/article/30/8/24-0007_article

Research Project: Elucidating the Pathobiology and Transmission of Transmissible Spongiform Encephalopathies

Location: Virus and Prion Research

Title: Differentiation of scrapie from chronic wasting disease in white-tailed deer

Author item LAMBERT, ZOE - Oak Ridge Institute For Science And Education (ORISE) item Bian, Jifeng item Cassmann, Eric item WEST GREENLEE, HEATHER - Iowa State University item Greenlee, Justin

Submitted to: Emerging Infectious Diseases Publication Type: Peer Reviewed Journal Publication Acceptance Date: 6/13/2024 Publication Date: N/A Citation: N/A

Interpretive Summary: Prion diseases are a neurodegenerative disease that can spread between animals. They are caused when the normal cellular prion protein misfolds and accumulates in the host’s central nervous system. This change is irreversible and invariably causes neurological disease and death of the host. The prion disease that affects sheep, scrapie, has been recognized for hundreds of years. However, chronic wasting disease, a similar disease found in white-tailed deer (WTD), has only been recognized since the 1960s. It has long been suggested that prion disease in deer (chronic wasting disease) was caused by the prion agent from sheep (scrapie). Recently, our lab confirmed that WTD will become infected by scrapie from sheep under conditions that mimic natural exposure. The disease produced in these animals was termed WTD scrapie. This manuscript addresses the next step in disease spread: whether sick WTD can pass WTD scrapie on to other deer. We found that white-tailed deer sick with scrapie can infect other deer under conditions mimicking natural exposure. The work reported in this manuscript demonstrates that CWD is difficult to differentiate from WTD scrapie. Regardless, WTD scrapie prions accumulate in the lymphoreticular system, meaning that environmental contamination is likely through feces, saliva, and other body fluids. Controlling WTD scrapie would require precautions similar to those taken with chronic wasting disease. The presence of WTD scrapie could confound mitigation efforts for chronic wasting disease. This information will be of interest to regulatory officials, the farmed cervid industry, and officials tasked with protecting animal health such as state Departments of Agriculture, Natural Resources, or Parks and Wildlife.

Technical Abstract: White-tailed deer (WTD) are susceptible to the scrapie agent from sheep after oronasal inoculation, termed WTD scrapie. However, results from western blotting these brainstems and lymph nodes are difficult to differentiate from WTD infected with chronic wasting disease (CWD). In order to assess the transmissibility of WTD scrapie and tissue phenotypes upon its further passage in WTD, three wildtype WTD (QQ95/GG96) were oronasally inoculated with WTD scrapie. These WTD presented with clinical signs and were euthanized between 21 and 26 months post-inoculation. Enzyme immunoassay (IDEXX) confirmed the presence of misfolded prion protein in the central nervous and lymphoreticular systems of all WTD in the study. Immunohistochemical staining, western blotting, and conformational stabilities were generally similar between the misfolded prion protein of WTD scrapie and CWD, though some differences were noted. Specifically, intraneuronal accumulation of misfolded prion protein was present in retinal ganglion cells of a WTD with WTD scrapie, not CWD. Additionally, epitope mapping revealed that the misfolded prion protein of CWD is slightly longer than that of WTD scrapie. Strong differences were seen in bioassays of cervidized mice, which exhibit significantly longer survival periods when inoculated with WTD scrapie as compared to those inoculated with CWD. Overall, this article establishes that WTD are highly susceptible to the WTD scrapie agent. Though subtle molecular differences exist between the misfolded prion protein of WTD scrapie and CWD, the presence of WTD scrapie in the lymphoreticular system determines that suspected cases be handled consistent with current guidelines for CWD.

https://www.ars.usda.gov/research/publications/publication/?seqNo115=410511

Title: Characterization of classical sheep scrapie in white-tailed deer after experimental oronasal exposure

Author item Greenlee, Justin item MOORE, SARAH - Orise Fellow item Cassmann, Eric item LAMBERT, ZOE - Orise Fellow item Kokemuller, Robyn item Smith, Jodi item Kunkle, Robert item KONG, QINGZHONG - Case Western Reserve University (CWRU) item WEST GREENLEE, HEATHER - Iowa State University

Submitted to: Journal of Infectious Diseases Publication Type: Peer Reviewed Journal Publication Acceptance Date: 11/4/2022 Publication Date: 11/8/2022

Citation: Greenlee, J.J., Moore, S.J., Cassmann, E.D., Lambert, Z.J., Kokemuller, R., Smith, J.D., Kunkle, R.A., Kong, Q., West Greenlee, H.M. 2022. Characterization of classical sheep scrapie in white-tailed deer after experimental oronasal exposure. Journal of Infectious Diseases. 227(12):1386-1395. Article jiac443. https://doi.org/10.1093/infdis/jiac443.

DOI: https://doi.org/10.1093/infdis/jiac443

Interpretive Summary: Chronic Wasting Disease (CWD), a fatal neurodegenerative disease that occurs in farmed and wild cervids (deer and elk) of North America, is a transmissible spongiform encephalopathy (TSE). TSEs are caused by infectious proteins called prions that are resistant to decontamination and environmental degradation. The origin of chronic wasting disease is not known, but it has many similarities to the TSE of sheep called scrapie. It has long been hypothesized that CWD could have arisen through transmission of sheep scrapie to deer. The purpose of this study was to determine if scrapie derived from sheep could be transmitted to white-tailed deer. This study reports that the deer inoculated with sheep scrapie developed clinical signs of TSE and that the abnormal prion protein could be detected in a wide range of neural and lymphoid tissues. These results indicate that deer may be susceptible to sheep scrapie if exposed to the disease in natural or agricultural settings . In addition, several strong similarities between CWD in white-tailed deer and the experimental cases of scrapie in white-tailed deer in this report suggest that it would be difficult to identify scrapie in deer were a case to occur. This information should be considered when developing plans to reduce or eliminate TSEs or advising farmers that wish to keep their deer herds free from prion diseases.

Technical Abstract: Scrapie is a prion disease of sheep and goats that is associated with widespread accumulation of abnormal prion protein (PrPSc) in the central nervous and lymphoid tissues. Chronic wasting disease (CWD) is the natural prion disease of cervid species and is similar to scrapie in sheep. The purpose of this study was to determine susceptibility of white-tailed deer (WTD) to the scrapie agent. We inoculated WTD (n=5) by a concurrent oral and intranasal exposure with the scrapie agent from sheep and (n=6) with the scrapie agent from goats. All deer exposed to the agent of scrapie from sheep had evidence of PrPSc accumulation. PrPSc was detected in lymphoid tissues at preclinical time points, and deer necropsied after 28 months post-inoculation had clinical signs, spongiform lesions, and widespread distribution of PrPSc in neural and lymphoid tissues. Western blots done on samples from the brainstem, cerebellum, and lymph nodes of scrapie-infected WTD have a molecular profile similar to CWD and distinct from western blots of samples from the cerebral cortex, retina, or the original sheep scrapie inoculum. WTD are susceptible to the agent of scrapie from sheep and differentiation from CWD may be difficult.

https://www.ars.usda.gov/research/publications/publication/?seqNo115=336834

ORIGIN OF CHRONIC WASTING DISEASE TSE PRION?COLORADO THE ORIGIN OF CHRONIC WASTING DISEASE CWD TSE PRION?

*** Spraker suggested an interesting explanation for the occurrence of CWD. The deer pens at the Foot Hills Campus were built some 30-40 years ago by a Dr. Bob Davis. At or abut that time, allegedly, some scrapie work was conducted at this site. When deer were introduced to the pens they occupied ground that had previously been occupied by sheep.

IN CONFIDENCE, REPORT OF AN UNCONVENTIONAL SLOW VIRUS DISEASE IN ANIMALS IN THE USA 1989

http://webarchive.nationalarchives.gov.uk/20080102193705/http://www.bseinquiry.gov.uk/files/mb/m11b/tab01.pdf

The occurrence of CWD must be viewed against the contest of the locations in which it occurred. It was an incidental and unwelcome complication of the respective wildlife research programmes. Despite its subsequent recognition as a new disease of cervids, therefore justifying direct investigation, no specific research funding was forthcoming. The USDA viewed it as a wildlife problem and consequently not their province!” page 26.

https://web.archive.org/web/20060307063531/http://www.bseinquiry.gov.uk/files/mb/m11b/tab01.pdf

***Moreover, sporadic disease has never been observed in breeding colonies or primate research laboratories, most notably among hundreds of animals over several decades of study at the National Institutes of Health25, and in nearly twenty older animals continuously housed in our own facility.

***> Even if the prevailing view is that sporadic CJD is due to the spontaneous formation of CJD prions, it remains possible that its apparent sporadic nature may, at least in part, result from our limited capacity to identify an environmental origin.

https://www.nature.com/articles/srep11573

***> ”Our data suggest that the phenotype of CWD in sheep is indistinguishable from some strains of scrapie in sheep. Given our results, current detection techniques would be unlikely to distinguish CWD in sheep from scrapie in sheep if cross-species transmission occurred naturally.” https://pubmed.ncbi.nlm.nih.gov/34047228/

https://journals.sagepub.com/doi/full/10.1177/10406387211017615

THURSDAY, JANUARY 08, 2026

Confucius Ponders, what about Wild Pigs (Sus scrofa) and CWD TSE Prion, and the Environment, what if?

Confucius Ponders, what about Wild Pigs (Sus scrofa), they can cover some distance rather quickly, what about Wild Pigs (Sus scrofa) digging up the terrain, and as they do it, what if these Wild Pigs (Sus scrofa) were exposed to CWD TSE Prion, and then they go on exposing and saturating the land with CWD TSE Prion, then the soil becomes contaminated with CWD TSE Prion, then what about the plants that grow from that soil for the decades to come, what if???

https://prpsc.proboards.com/thread/190/confucius-ponders-wild-pigs-scrofa

https://chronic-wasting-disease.blogspot.com/2026/01/confucius-ponders-what-about-wild-pigs.html

***> Chronic wasting disease prions in cervids and wild pigs in North America Preliminary Outbreak Assessment DEFRA 26 January 2026

CWD has continued to spread among captive and free-ranging cervids in North America since it was first detected in the 1960s. The finding of CWD prions in wild pigs in the USA suggests they could contribute towards transmission of the disease, influencing its epidemiology, geographic distribution and interspecies spread. However, further research is needed to confirm this. CWD has never been reported in Great Britain and the current risk of CWD prions being introduced into Great Britain’s wild pig or cervid population ranges from very low to negligible.

https://assets.publishing.service.gov.uk/media/697a3b013c71d838df6bd413/CWD_Prions_in_Cervids_and_Wild_Pigs_in_North_America.pdf

Price of TSE Prion Poker goes up substantially, all you cattle ranchers and such, better pay close attention here...terry

"Cattle with the E211K polymorphism are susceptible to the CWD agent after oronasal exposure of 0.2 g of infectious material."

Transmission of the chronic wasting disease agent from elk to cattle after oronasal exposure

Justin Greenlee, Jifeng Bian, Zoe Lambert, Alexis Frese, and Eric Cassmann Virus and Prion Research Unit, National Animal Disease Center, USDA-ARS, Ames, IA, USA

Aims: The purpose of this study was to determine the susceptibility of cattle to chronic wasting disease agent from elk.

Materials and Methods: Initial studies were conducted in bovinized mice using inoculum derived from elk with various genotypes at codon 132 (MM, LM, LL). Based upon attack rates, inoculum (10% w/v brain homogenate) from an LM132 elk was selected for transmission studies in cattle. At approximately 2 weeks of age, one wild type steer (EE211) and one steer with the E211K polymorphism (EK211) were fed 1 mL of brain homogenate in a quart of milk replacer while another 1 mL was instilled intranasally. The cattle were examined daily for clinical signs for the duration of the experiment. One steer is still under observation at 71 months post-inoculation (mpi).

Results: Inoculum derived from MM132 elk resulted in similar attack rates and incubation periods in mice expressing wild type or K211 bovine PRNP, 35% at 531 days post inoculation (dpi) and 27% at 448 dpi, respectively. Inoculum from LM132 elk had a slightly higher attack rates in mice: 45% (693 dpi) in wild type cattle PRNP and 33% (468) in K211 mice. Inoculum from LL132 elk resulted in the highest attack rate in wild type bovinized mice (53% at 625 dpi), but no K211 mice were affected at >700 days. At approximately 70 mpi, the EK211 genotype steer developed clinical signs suggestive of prion disease, depression, low head carriage, hypersalivation, and ataxia, and was necropsied. Enzyme immunoassay (IDEXX) was positive in brainstem (OD=4.00, but non-detect in retropharyngeal lymph nodes and palatine tonsil. Immunoreactivity was largely limited to the brainstem, midbrain, and cervical spinal cord with a pattern that was primarily glia-associated.

Conclusions: Cattle with the E211K polymorphism are susceptible to the CWD agent after oronasal exposure of 0.2 g of infectious material.

Prion 2023 Congress Organizing Committee and the NeuroPrion Association, we invite you to join us for the International Conference Prion2023 from 16-20 October 2023 in Faro, Portugal.

https://prion2023.org/wp-content/uploads/2023/10/Meeting-book-final-version2.pdf

https://web.archive.org/web/20250828201533/https://prion2023.org/wp-content/uploads/2023/10/Meeting-book-final-version2.pdf

https://www.researchgate.net/profile/Syed-Zahid-Shah/publication/378314391_Meeting-book-final-version_prion_2023/links/65d44dad28b7720cecdca95f/Meeting-book-final-version-prion-2023.pdf

Component 6: Transmissible Spongiform Encephalopathies

Sheep scrapie agent can infect white-tailed deer after oronasal exposure.

The origin of chronic wasting disease (CWD) is not known, but it has many similarities to the sheep prion disease called scrapie. It has long been hypothesized that CWD arose through transmission of sheep scrapie to deer. ARS researchers in Ames, Iowa, conducted research to determine if scrapie derived from sheep could be transmitted to white-tailed deer. The deer inoculated with sheep scrapie developed clinical signs and the abnormal prion protein could be detected in a wide range of tissues. These results indicate that deer may be susceptible to sheep scrapie if exposed to the disease in natural or agricultural settings. In addition, several strong similarities between CWD in white-tailed deer and the experimental cases of scrapie in white-tailed deer suggests that it would be difficult to distinguish scrapie from CWD in deer or identify scrapie if a case occurs. This information should be considered by deer farmers for keeping their herds free from prion diseases.

https://www.ars.usda.gov/ARSUserFiles/np103/AnnualReports/NP103%20FY2023%20Annual%20Report_Final.pdf

PLoS One. 2020 Aug 20;15(8):e0237410. doi: 10.1371/journal.pone.0237410. eCollection 2020.

Very low oral exposure to prions of brain or saliva origin can transmit chronic wasting disease

Nathaniel D Denkers 1 , Clare E Hoover 2 , Kristen A Davenport 3 , Davin M Henderson 1 , Erin E McNulty 1 , Amy V Nalls 1 , Candace K Mathiason 1 , Edward A Hoover 1

PMID: 32817706 PMCID: PMC7446902 DOI: 10.1371/journal.pone.0237410

These studies suggest that the CWD minimum infectious dose approximates 100 to 300 ng CWD-positive brain (or saliva equivalent), and that CWD infection appears to conform more with a threshold than a cumulative dose dynamic.

Snip…

Discussion

As CWD expands across North America and Scandinavia, how this disease is transmitted so efficiently remains unclear, given the low concentrations of prions shed in secretions and excretions [13, 14]. The present studies demonstrated that a single oral exposure to as little as 300nmg of CWD-positive brain or equivalent saliva can initiate infection in 100% of exposed white-tailed deer. However, distributing this dose as 10, 30 ng exposures failed to induce infection. Overall, these results suggest that the minimum oral infectious exposure approaches 100 to 300 ng of CWD-positive brain equivalent. These dynamics also invite speculation as to whether potential infection co-factors, such as particle binding [46, 47] or compromises in mucosal integrity may influence infection susceptibility, as suggested from two studies in rodent models [48, 49].

https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0237410

PRION 2023 CONTINUED;

https://prion2023.org/wp-content/uploads/2023/10/Meeting-book-final-version2.pdf

https://web.archive.org/web/20250828201533/https://prion2023.org/wp-content/uploads/2023/10/Meeting-book-final-version2.pdf

https://www.researchgate.net/profile/Syed-Zahid-Shah/publication/378314391_Meeting-book-final-version_prion_2023/links/65d44dad28b7720cecdca95f/Meeting-book-final-version-prion-2023.pdf

Prion 2023 Experimental Oronasal Inoculation of the Chronic Wasting Disease Agent into White Tailed Deer

Aims: The purpose of this experiment was to determine whether white-tailed deer (WTD) are susceptible to inoculation of chronic wasting disease (CWD) via oronasal exposure.

Materials and methods: Six male, neutered WTD were oronasally inoculated with brainstem material (10% w/v) from a CWD-positive wild-type WTD. The genotypes of five inoculated deer were Q95/G96 (wild-type). One inoculated deer was homozygous S at codon 96 (96SS). Cervidized (Tg12; M132 elk PrP) mice were inoculated with 1% w/v brainstem homogenate from either a 96GG WTD (n=10) or the 96SS WTD (n=10).

Results: All deer developed characteristic clinical signs of CWD including weight loss, regurgitation, and ataxia. The 96SS individual had a prolonged disease course and incubation period compared to the other deer. Western blots of the brainstem on all deer yielded similar molecular profiles. All deer had widespread lymphoid distribution of PrPCWD and neuropathologic lesions associated with transmissible spongiform encephalopathies. Both groups of mice had a 100% attack rate and developed clinical signs, including loss of body condition, ataxia, and loss of righting reflex. Mice inoculated with material from the 96SS deer had a significantly shorter incubation period than mice inoculated with material from 96GG deer (Welch two sample T-test, P<0.05). Serial dilutions of each inocula suggests that differences in incubation period were not due to a greater concentration of PrPCWD in the 96SS inoculum. Molecular profiles from western blot of brain homogenates from mice appeared similar regardless of inoculum and appear similar to those of deer used for inoculum.

Conclusions: This study characterizes the lesions and clinical course of CWD in WTD inoculated in a similar manner to natural conditions. It supports previous findings that 96SS deer have a prolonged disease course. Further, it describes a first pass of inoculum from a 96SS deer in cervidized mice which shortened the incubation period.

=====end

PRION 2023 CONTINUED;

https://prion2023.org/wp-content/uploads/2023/10/Meeting-book-final-version2.pdf

https://web.archive.org/web/20250828201533/https://prion2023.org/wp-content/uploads/2023/10/Meeting-book-final-version2.pdf

https://www.researchgate.net/profile/Syed-Zahid-Shah/publication/378314391_Meeting-book-final-version_prion_2023/links/65d44dad28b7720cecdca95f/Meeting-book-final-version-prion-2023.pdf

SCRAPIE TSE Prion USA RAPID RESPONSE URGENT UPDATES DECEMBER 25, 2025

https://scrapie-usa.blogspot.com/2025/12/scrapie-tse-prion-usa-rapid-response.html

https://prpsc.proboards.com/thread/186/scrapie-prion-response-urgent-updates

TUESDAY, SEPTEMBER 30, 2025

USDA EXPLANATORY NOTES ANIMAL AND PLANT HEALTH INSPECTION SERVICE 2025-2014 CHRONIC WASTING DISEASE CWD TSE CERVID

https://chronic-wasting-disease.blogspot.com/2025/09/usda-explanatory-notes-animal-and-plant.html

TUESDAY, SEPTEMBER 30, 2025

USDA National Scrapie Program History and Bovine Spongiform Encephalopathy BSE TSE Update 2025

https://bovineprp.blogspot.com/2025/09/usda-national-scrapie-program-history.html

TUESDAY, SEPTEMBER 30, 2025

USDA National Scrapie Program History and Bovine Spongiform Encephalopathy BSE TSE Update 2025

https://scrapie-usa.blogspot.com/2025/09/usda-national-scrapie-program-history.html

***> CWD Action Plan National Program 103 Animal Health 2022-2027 UPDATE JANUARY 2026

https://prpsc.proboards.com/thread/189/action-national-program-animal-health

https://chronic-wasting-disease.blogspot.com/2026/01/cwd-action-plan-national-program-103.html

Research Project: Elucidating the Pathobiology and Transmission of Transmissible Spongiform Encephalopathies

Location: Virus and Prion Research

2025 Annual Report

https://transmissiblespongiformencephalopathy.blogspot.com/2025/12/ars-research-elucidating-pathobiology.html

THURSDAY, APRIL 10, 2025

***> CWD TSE Prion, Politics, Friendly Fire, Unforeseen Consequences, What If? <***

https://chronic-wasting-disease.blogspot.com/2025/04/cwd-tse-prion-politics-friendly-fire.html

Texas TPWD Confirms 116 More Cases CWD, Total To Date 1,215 Positives  

TPWD CWD Dashboard 1,215 Total Positive Samples

https://experience.arcgis.com/experience/8f6c27330c444a19b4b57beb7ffabb8b/page/Dashboard#data_s=id%3AdataSource_3-1966d773e34-layer-10%3A2

https://chronic-wasting-disease.blogspot.com/2025/12/texas-tpwd-confirms-116-more-cases-cwd.html

Trucking CWD TSE Prion

Chronic Wasting Disease CWD TSE Prion of Cervid

“CWD spreads among wild populations at a relatively slow rate, limited by the natural home range and dispersed nature of wild animals.”

NOW HOLD YOUR HORSES, Chronic Wasting Disease CWD of Cervid can spread rather swiftly, traveling around 50 MPH, from the back of truck and trailer, and Here in Texas, we call it ‘Trucking CWD’…

Preventive Veterinary Medicine Volume 234, January 2025, 106385

Use of biosecurity practices to prevent chronic wasting disease in Minnesota cervid herds

Vehicles or trailers that entered the farm were used to transport other live cervids, cervid carcasses, or cervid body parts in past 3 years in 64.3 % (95 % CI 46.3–82.3) of larger elk/reindeer herds compared to 13.6 % (95 % CI 4.7–22.4) of smaller deer herds.

Snip…

Identifying the exact pathway of initial CWD transmission to cervid herds is often not possible, in part due to many potential pathways of transmission for the infection, including both direct and indirect contact with infected farmed or wild cervids (Kincheloe et al., 2021). That study identified that transmissions from infected farmed cervids may occur from direct contact with the movement of cervids from one herd to another and from indirect contact with the sharing of equipment, vehicles, clothing, reproductive equipment, and potentially through semen or embryos.

https://www.sciencedirect.com/science/article/abs/pii/S016758772400271X

“Chronic Wasting Disease (CWD) is a fatal neurological disease and can devastate deer populations by silently spreading through direct animal contact and contaminated environments. Without close monitoring, illegal movement of captive deer increases the risk of introducing CWD to areas it is not known to exist, potentially leading to widespread outbreaks which will impact more than just the health of Texas deer.”

https://tpwd.texas.gov/newsmedia/releases/?req=20250227b

Texas Game Wardens Near Conclusion of ‘Ghost Deer’ Case with 24 Suspects, 1,400 Charges Filed Statewide

Aug. 14, 2025

Media Contact: TPWD News, Business Hours, 512-389-8030

AUSTIN – The Texas Game Warden investigation known as "Ghost Deer" has reached a possible conclusion after two additional suspects turned themselves in on felony charges. This brings the total number of individuals implicated in the case to 24, with approximately 1,400 charges filed across 11 Texas counties.

Ken Schlaudt, 64, of San Antonio, the owner of four deer breeding facilities and one release site, along with facility manager Bill Bowers, 55, of San Angelo, surrendered to the Travis County District Attorney’s Office on charges of felony tampering with a governmental record. Both men allegedly entered false information into the Texas Wildlife Information Management System (TWIMS) to facilitate illegal smuggling of white-tailed breeder deer. They also face more than 100 misdemeanor charges related to unlawful breeder deer activities in Tom Green County.

The "Ghost Deer" investigation has uncovered widespread, coordinated deer breeding violations including, but not limited to: smuggling captive breeder deer and free-range whitetail deer between breeder facilities and ranches, Chronic Wasting Disease (CWD) testing violations, license violations and misdemeanor and felony drug charges relating to the possession and mishandling of prescribed sedation drugs classified as controlled substances.

The suspects charged in the case include:

Evan Bircher, 59, San Antonio Vernon Carr, 55, Corpus Christi Jarrod Croaker, 47, Corpus Christi Terry Edwards, 54, Angleton Joshua Jurecek, 41, Alice Justin Leinneweber, 36, Orange Grove James Mann, 53, Odem Gage McKinzie, 28, Normanna Herbert “Tim” McKinzie, 47, Normanna Eric Olivares, 47, Corpus Christi Bruce Pipkin, 57, Beaumont Dustin Reynolds, 38, Robstown Kevin Soto, 55, Hockley Jared Utter, 52, Pipe Creek Reed Vollmering, 32, Orange Grove Clint West, 56, Beaumont James Whaley, 49, Sevierville, Tenn. Ryder Whitstine, 19, Rockport Ryker Whitstine, 21, Rockport Claude Wilhelm, 52, Orange Cases are pending adjudication in Bandera, Bee, Brazoria, Duval, Edwards, Jim Wells, Live Oak, Montgomery, Tom Green, Travis and Webb counties.

The investigation began in March 2024 when game wardens discovered the first violations during a traffic stop.

resulting in one of the largest deer smuggling operations in Texas history.

https://tpwd.texas.gov/newsmedia/releases/?req=20250814c

https://tpwd.texas.gov/newsmedia/releases/?req=20250206a

That incident led wardens to the much larger network of violations,

https://tpwd.texas.gov/newsmedia/releases/?req=20250227b

About Texas Game Wardens

Texas Game Wardens, within the Law Enforcement Division of Texas Parks and Wildlife Department, are responsible for enforcing laws related to the conservation and management of natural resources and public safety through community-based law enforcement. Their mission is to provide hunting, fishing and outdoor recreation opportunities for the use and enjoyment of present and future generations. Additionally, they play a crucial role in search and rescue operations during natural disasters, exemplifying their commitment to protecting both the environment and the people of Texas.

If you witness a fishing, wildlife or boating violation in progress, please call 1-800-792-GAME(4263) immediately and report it to Operation Game Thief (OGT), Texas’ Wildlife Crime-Stoppers Program. You can also text your tip by sending the keyword TXOGT plus your tip to 847411 or through the Texas OGT App, available for iOS and Android devices. Dispatchers are available 24/7.

https://tpwd.texas.gov/newsmedia/releases/?req=20250814c

Texas Chronic Wasting Disease CWD TSE Prion Dashboard Update August 2025

SEE NEW DASHBOARD FOR CWD POSITIVES!

https://experience.arcgis.com/experience/8f6c27330c444a19b4b57beb7ffabb8b/page/Dashboard#data_s=id%3AdataSource_3-1966d773e34-layer-10%3A29

Texas CWD total by calendar years

https://chronic-wasting-disease.blogspot.com/2024/12/texas-cwd-tse-prion-positive-samples-by.html

https://tpwd.texas.gov/huntwild/wild/diseases/cwd/positive-cases/listing-cwd-cases-texas.phtml#texasCWD

Counties where CWD Exposed Deer were Released

https://tpwd.texas.gov/documents/257/CWD-Trace-OutReleaseSites.pdf

Number of CWD Exposed Deer Released by County

https://tpwd.texas.gov/documents/258/CWD-Trace-OutReleaseSites-NbrDeer.pdf

CWD Status Captive Herds

https://www.aphis.usda.gov/sites/default/files/status-of-captive-herds.pdf

TAHC 425th Commission Meeting CWD 1:45:00

* See CWD speakers expressing their concerns with changed regulations…

2:00 hr mark

https://m.youtube.com/watch?v=bWawHpdn_7I

TEXAS ANIMAL HEALTH COMMISSION 423rd Commission Meeting CWD Update February 25, 2025

https://chronic-wasting-disease.blogspot.com/2025/02/texas-animal-health-commission-423rd.html

Texas Kimble County Farm Chronic Wasting Disease CWD TSE Prion Approximate Herd Prevalence 12%

SUMMARY MINUTES OF THE 407th COMMISSION MEETING Texas Animal Health Commission

September 22, 2020

http://web.archive.org/web/20201017124040/https://www.tahc.texas.gov/agency/meetings/minutes/SummaryMinutes_CommMtg_2020-09-22.pdf

APHIS USDA Captive CWD Herds Update by State December 2025 Update

CHRONIC WASTING DISEASE CASES

Date of Index Case Confirmation Index Case State County Species Herd Type HCP Enrolled HCP Certified Number of Animals Herd Status

11/1/2025 ukn TX Limestone WTD Hunt No No 132 Quarantine

10/27/2025 3 YR Make WI Richland WTD Breeder Yes Yes ukn Quarantine

10/9/2025 2 YR Female TX Duvall WTD Breeder No No 94+ Quarantine

10/9/2025 2 YR Male PA Franklin WTD Breeder No No 23 Quarantine

10/8/2025 3.5 YR Male PA Huntingdon WTD Hobby No No 2 Quarantine

10/8/2025 3 YR Male WI Portage WTD Fallow Hunt No No 132 Quarantine

9/26/2025 8.5 YR Female TX Navaro WTD Breeder No No 650 Quarantine

9/16/2025 3 YR Female PA Dauphin WTD Breeder Yes Yes 85 Quarantine

9/5/2025 3 YR Male TX Duvall WTD Breeder No No 107+ Quarantine

8/6/2025 Adult Female PA Fulton WTD Breeder No No 14 Quarantine

7/21/2025 4 YR Female PA Bedford WTD Breeder No No 34 Quarantine

Updated December 2025 CHRONIC WASTING DISEASE CASES

6/3/2025 11 YR Female PA Blair WTD Breeder No No 45 Quarantine

6/3/2025 8 YR Female PA Bedford WTD Breeder No No 6 Quarantine

5/16/2025 5.5 YR Female WI Rock WTD Breeder No No ~46 Quarantine

5/14/2025 3 YR Female UT Weber Elk Hunt No No ukn Quarantine

4/30/2025 4.5 YR Male PA Jefferson WTD Hunt No No 36 Depopulated

4/18/2025 10+ YR Ukn TX Zavala WTD Hunt No No 190 Quarantine

4/9/2025 6 YR Male MI Montcalm WTD Breeder No No 86 Quarantine

3/28/2025 3.5 YR Male PA Huntingdon WTD Hobby No No 2 Quarantine

3/28/2025 3.5 YR Female PA Wayne Red Deer Hunt No no 31 Depopulated

2/26/2025 1.5 YR Male TX Kauffman WTD Breeder Yes Yes 400 Quarantine

2/26/2025 3.5 Yr Male PA Lancaster WTD Breeder Yes Yes 105 Quarantine

2/21/2025 4 YR Male CO Montrose Elk Hunt No No 97 Quarantine

Updated December 2025 CHRONIC WASTING DISEASE CASES

2/21/2025 7 YR Female MI Osceola WTD Hunt No No 201 Quarantine

2/10/2025 3.5 YR Male PA Perry WTD Hunt No No 15 Quarantine

1/7/2025 4 YR Female CO Mesa Elk Hunt No No 217 Quarantine

1/7/2025 2 YR Male UT Duchesne Elk Hunt No No 0 No animals

snip…see more;

https://www.aphis.usda.gov/sites/default/files/status-of-captive-herds.pdf

Remember, imho, a quarantined captive CWD Herd, is a ticking environmental time bomb just waiting to go off, the longer held in quarantine, the greater chance of environmental spread of CWD. litigation of CWD can take what seems to be an eternity, and CWD TSE Prion saturation into the environment grows each day left in quarantine. …terry

APHIS USDA Captive CWD Herds Update by State December 2025 Update

https://chronic-wasting-disease.blogspot.com/2025/12/aphis-usda-captive-cwd-herds-update-by.html

https://prpsc.proboards.com/thread/187/aphis-captive-herds-update-december

***> CWD TSE PrP Environmental Factors <***

Chronic wasting disease (CWD) prion detection in environmental and biological samples from a taxidermy site and nursing facility, and instruments used in surveillance activities

Available online 9 April 2025

Highlights

• CWD prions were identified in a taxidermy and deer nursing facility.

• Contaminated samples included waters, soils, dermestid beetles, domestic flies and a dumpster.

• Surgical instruments used to collect deer samples can get contaminated with CWD prions.

• Some of the infectious particles are readily released from surgical instruments when washed.

• Our results suggest that taxidermy practices actively contribute in the spreading of CWD.

Snip…

In summary, the information provided in this report demonstrate how anthropogenic activities, specifically taxidermy practices, animal processing, and rehabilitation of CWD susceptible species, may facilitate CWD transmission through the environmental dissemination of CWD prions. This study, along with future research efforts characterizing the overall level of infectivity, provides relevant information on managing CWD and to control its rapid geographic expansion. …

https://www.sciencedirect.com/science/article/abs/pii/S0048969725009544

Chronic wasting disease detection in environmental and biological samples from a taxidermy site

Results: The PMCA analysis demonstrated CWD seeding activity in some of the components of this facility, including insects involved in head processing, soils, and a trash dumpster.

Conclusions: Different areas of this property were used for various taxidermy procedures. We were able to detect the presence of prions in

i) soils that were in contact with the heads of dead animals, ii) insects involved in the cleaning of skulls, and iii) an empty dumpster where animal carcasses were previously placed.

This is the first report demonstrating that swabbing is a helpful method to screen for prion infectivity on surfaces potentially contaminated with CWD. These findings are relevant as this swabbing and amplification strategy may be used to evaluate the disease status of other free-ranging and captive settings where there is a concern for CWD transmissions, such as at feeders and water troughs with CWD-exposed properties. This approach could have substantial implications for free-ranging cervid surveillance as well as in epidemiological investigations of CWD.

Prion 2022 Conference abstracts: pushing the boundaries

https://www.tandfonline.com/doi/full/10.1080/19336896.2022.2091286

Artificial mineral sites that pre-date endemic chronic wasting disease become prion hotspots

The Ames Research and Educational Center property, centrally located within the CWD zone of southwest Tennessee, contains 49 historical mineral supplementation sites that were decommissioned in 2012. Here, we demonstrate that 32 of the 49 (65%) mineral sites within Ames established prior to the regional CWD outbreak, serve as foci of environmental PrPCWD contamination. Detection of PrPCWD in soils from these artificial mineral sites was dependent on site-specific management efforts. Soil physical properties were very similar across sites and no correlation between PrPCWD detection and soil physical properties was found. The detection of PrPCWD in soils at attractant sites within an endemic CWD zone significantly advances our understanding of environmental PrPCWD accumulation dynamics, providing valuable information for advancing adaptive CWD management approaches.

https://intcwdsympo.files.wordpress.com/2023/06/final-agenda-with-abstracts.pdf

Shedding of Chronic Wasting Disease Prions in Multiple Excreta Throughout Disease Course in White-tailed Deer

Conclusions: These studies demonstrate: (a) CWD prion excretion occurs throughout infection; (2) PRNP genotype (GG≫GS/NT) influences the excreta shedding; and (3) detection sensitivity in excreta can vary with different RT-QuIC protocols. These results provide a more complete perspective of prion shedding in deer during the course of CWD infection.

Prion 2022 Conference abstracts: pushing the boundaries

https://www.tandfonline.com/doi/full/10.1080/19336896.2022.2091286

Front. Vet. Sci., 14 September 2015 | doi.org/10.3389/fvets.2015.00032

Objects in contact with classical scrapie sheep act as a reservoir for scrapie transmission

In conclusion, the results in the current study indicate that removal of furniture that had been in contact with scrapie-infected animals should be recommended, particularly since cleaning and decontamination may not effectively remove scrapie infectivity (31), even though infectivity declines considerably if the pasture and the field furniture have not been in contact with scrapie-infected sheep for several months. As sPMCA failed to detect PrPSc in furniture that was subjected to weathering, even though exposure led to infection in sheep, this method may not always be reliable in predicting the risk of scrapie infection through environmental contamination.

journal.frontiersin.org/article/10.3389/fvets.2015.00032/full

SUNDAY, APRIL 06, 2025

Failure to prevent classical scrapie after repeated decontamination of a barn

scrapie-usa.blogspot.com/2025/04/failure-to-prevent-classical-scrapie.html

prpsc.proboards.com/thread/165/failure-prevent-scrapie-repeated-decontamination

"Additionally, we have determined that prion seeding activity is retained for at least fifteen years at a contaminated site following attempted remediation."

15 YEARS!

Detection of prions in soils contaminated by multiple routes

Results: We are able to detect prion seeding activity at multiple types of environmental hotspots, including carcass sites, contaminated captive facilities, and scrapes (i.e. urine and saliva). Differences in relative prion concentration vary depending on the nature and source of the contamination. Additionally, we have determined that prion seeding activity is retained for at least fifteen years at a contaminated site following attempted remediation.

Conclusions: Detection of prions in the environment is of the utmost importance for controlling chronic wasting disease spread. Here, we have demonstrated a viable method for detection of prions in complex environmental matrices. However, it is quite likely that this method underestimates the total infectious prion load in a contaminated sample, due to incomplete recovery of infectious prions. Further refinements are necessary for accurate quantification of prions in such samples, and to account for the intrinsic heterogeneities found in the broader environment.

Funded by: Wisconsin Department of Natural Resources

Meeting-book-final-version prion 2023 Prion 2023 Congress Organizing Committee and the NeuroPrion Association, we invite you to join us for the International Conference Prion2023 from 16-20 October 2023 in Faro, Portugal.

web.archive.org/web/20250828201533/https://prion2023.org/wp-content/uploads/2023/10/Meeting-book-final-version2.pdf

www.researchgate.net/profile/Syed-Zahid-Shah/publication/378314391_Meeting-book-final-version_prion_2023/links/65d44dad28b7720cecdca95f/Meeting-book-final-version-prion-2023.pdf

***> Infectious agent of sheep scrapie may persist in the environment for at least 16 years

***> Nine of these recurrences occurred 14–21 years after culling, apparently as the result of environmental contamination, but outside entry could not always be absolutely excluded.

JOURNAL OF GENERAL VIROLOGY Volume 87, Issue 12

Infectious agent of sheep scrapie may persist in the environment for at least 16 years Free

https://www.microbiologyresearch.org/content/journal/jgv/10.1099/vir.0.82011-0

Rapid recontamination of a farm building occurs after attempted prion removal

First published: 19 January 2019 https://doi.org/10.1136/vr.105054

The data illustrates the difficulty in decontaminating farm buildings from scrapie, and demonstrates the likely contribution of farm dust to the recontamination of these environments to levels that are capable of causing disease. snip...

This study clearly demonstrates the difficulty in removing scrapie infectivity from the farm environment. Practical and effective prion decontamination methods are still urgently required for decontamination of scrapie infectivity from farms that have had cases of scrapie and this is particularly relevant for scrapie positive goatherds, which currently have limited genetic resistance to scrapie within commercial breeds.24 This is very likely to have parallels with control efforts for CWD in cervids.

https://bvajournals.onlinelibrary.wiley.com/doi/abs/10.1136/vr.105054

***>This is very likely to have parallels with control efforts for CWD in cervids.

https://pubmed.ncbi.nlm.nih.gov/30602491/

I remember what “deep throat” told me about Scrapie back around 2001, during early days of my BSE investigation, after my Mom died from hvCJD, I never forgot, and it seems it’s come to pass;

***> Confidential!!!!

***> As early as 1992-3 there had been long studies conducted on small pastures containing scrapie infected sheep at the sheep research station associated with the Neuropathogenesis Unit in Edinburgh, Scotland. Whether these are documented...I don't know. But personal recounts both heard and recorded in a daily journal indicate that leaving the pastures free and replacing the topsoil completely at least 2 feet of thickness each year for SEVEN years....and then when very clean (proven scrapie free) sheep were placed on these small pastures.... the new sheep also broke out with scrapie and passed it to offspring. I am not sure that TSE contaminated ground could ever be free of the agent!! A very frightening revelation!!!

---end personal email---end...tss

and so it seems…

Chronic Wasting Disease CWD TSE Prion

THE CWD TSE Prion aka mad cow type disease is not your normal pathogen.

The TSE prion disease survives ashing to 600 degrees celsius, that’s around 1112 degrees farenheit.

You cannot cook the TSE prion disease out of meat. In fact new data now shows that exposure to high temperatures used to cook the meat increased the availability of prions for in vitro amplification.

you can take the ash and mix it with saline and inject that ash into a mouse, and the mouse will go down with TSE.

Prion Infected Meat-and-Bone Meal Is Still Infectious after Biodiesel Production as well.

the TSE prion agent also survives Simulated Wastewater Treatment Processes.

IN fact, you should also know that the TSE Prion agent will survive in the environment for years, if not decades.

you can bury it and it will not go away.

The TSE agent is capable of infected your water table i.e. Detection of protease-resistant cervid prion protein in water from a CWD-endemic area.

it’s not your ordinary pathogen you can just cook it out and be done

New studies on the heat resistance of hamster-adapted scrapie agent: Threshold survival after ashing at 600°C suggests an inorganic template of replication

http://www.pnas.org/content/97/7/3418.full

Prion Infected Meat-and-Bone Meal Is Still Infectious after Biodiesel Production

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2493038/

Rapid assessment of bovine spongiform encephalopathy prion inactivation by heat treatment in yellow grease produced in the industrial manufacturing process of meat and bone meals

https://bmcvetres.biomedcentral.com/track/pdf/10.1186/1746-6148-9-134.pdf

THURSDAY, FEBRUARY 28, 2019

BSE infectivity survives burial for five years with only limited spread

https://link.springer.com/content/pdf/10.1007%2Fs00705-019-04154-8.pdf

Chronic wasting disease prions on deer feeders and wildlife visitation to deer feeding areas

First published: 10 February 2025

Snip…

Finally, we swabbed 19 feeders in 2 areas where CWD was newly detected, finding prion contamination on swabs from 4 feeders. We show that deer feeders in free-ranging populations with high CWD prevalence become contaminated with CWD prions quickly, becoming a potential site of exposure of deer to CWD prions. Our results also demonstrate the ability to find evidence of prion contamination on deer feeders, even in areas where CWD is newly detected.

Snip…

We found that supplemental feeding increased the risk of exposure to CWD prions due to contamination of feeders, increased deer visitation, and increased deer-to-deer contact.

The 12-fold increase in deer visitation to feeders compared to mast trees and 2-fold increase compared to food plots demonstrates increased risk for direct disease spread.

https://wildlife.onlinelibrary.wiley.com/doi/10.1002/jwmg.70000

Chronic Wasting Disease in Texas A Real Disease with Proven Impacts

Produced by a coalition of concerned hunters, landowners, & conservationists (last update 1/2025)

storymaps.arcgis.com/stories/b93f528938ac48e9b56dcc79953cbec0

CWD HERD DECLINES

Arkansas CWD Deer Study Final 2025

4. Objective 4 and 6 - Infection rates and population modeling

a. In 2024, CWD sample prevalence was 40% across the study area, with higher rates seen in males (65%) than in females (34%).

b. Approximately 50% of males tested positive for CWD by the age of 2.5.

c. White-tailed deer abundance in the study area declined, driven by reduced lifespans and lower lifetime reproduction.

d. If survival does not increase, this population is expected to continue to decline.

https://drive.google.com/file/d/1jN5mtvXvz7IYFDQjv4Rasrw60dGe4KMJ/view

Louisiana House of Representative Aug 27, 9:30 AM, HCR-6 CWD

Louisiana House of Representative

Chronic Wasting Disease CWD

(A letter written from a Mississippi farmer who’s farm has been in his family for more than 100 years, and submitted it in this video presentation, 28 minute mark, another wake up call for sure, of what some have been warning for years, about CWD, but sadly will go by the wayside by the conspiracy theorists spreading fake news…terry)

Alston Ross

Marshall County, Mississippi

My family owns a 2,000 acre farm in Marshall County, which is in North Mississippi. CWD has plagued my farm since 2018 and has become progressively worse over time. We no longer have mature deer over the age of 3 years old on our property. Every buck harvested on our land has tested positive this year. The owners of our neighboring properties have continued to feed deer and ignore MDWFP regulations, which has exacerbated the spread of the disease throughout our area. This farm has been in my family for over 100 years, and due to the rapid spread of CWD, we are concerned about the future of our deer herd and the value of our hunting land…end

Snip…

Arkansas

Snip…

40:35 “…and conversely, I was co-Principle Investigator in NW Arkansas, where prevalence is approaching 50 percent.”

Snip…

41:00 “Specific to the work in Arkansas, in 2020, the state agency was showing the Prevalence at 30 percent in the Northwest part of the State, so flip a coin, so, 1 out of every 3 deer had the disease. We started that research in 2020, and now, the prevalence rate is now exceeding 40% in both sexes, and 50% in males.”

43:00 “what we’re seeing Arkansas now is, that population is declining about 11% a year.”

Snip…see full video presentation;

https://house.louisiana.gov/H_Video/VideoArchivePlayer?v=house/2025/Aug/0827_25_NR_Joint

CWD IS RAVAGING MY FAMILY’S LAND, BUT IT’S NOT TOO LATE FOR YOU

September 9, 2025 By: Paul Annear

My first season deer hunting in Wisconsin was 2001, the same season that produced Wisconsin’s first deer to test positive for chronic wasting disease. CWD has always been at the forefront of deer hunting discussions in my time as a hunter, and I’ve watched the disease slowly spread and worsen. Since 2019, eight of 11 deer I’ve taken on my family’s property in Richland County in Southwest Wisconsin have tested positive for CWD – including the buck in the photo above.

Aside from harvesting otherwise perfectly healthy-looking deer that test positive for CWD, we are now seeing live deer walking around in the awful final stages of this disease. Research has now confirmed what I’ve seen occurring on our hunting land in the last five to six years: CWD is beginning to reduce deer populations in high-prevalence areas like mine.

It didn’t have to reach this point. Hunters in areas with low CWD prevalence can keep infection rates low and deer populations healthy overall by accepting and implementing certain strategies. Some of the strategies I will lay out will challenge you as a hunter to play the “long game,” but there are ways to slow the spread of CWD in areas where it is newly discovered and infection rates are still low.

If you’re rolling your eyes at another guy talking about CWD, I get it, but I urge you to keep reading. Hear my personal story, how it has affected my hunting experiences, and what can happen if hunters ignore CWD.

“Where Are the Deer?”

…snip…see full text;

https://deerassociation.com/cwd-is-ravaging-my-familys-land-but-its-not-too-late-for-you/

Southwest Wisconsin CWD, Deer and Predator Study

key takeaways ;

CWD substantially reduces deer survival rates and suppresses population growth.

Where CWD prevalence is high, deer populations are likely declining. 

If CWD continues to spread, it will eventually impact deer populations elsewhere.

https://dnr.wisconsin.gov/topic/research/projects/dpp/StudyResults

MONDAY, APRIL 28, 2025

Wisconsin DNR 2024 CWD 1,786 samples testing positive

https://chronic-wasting-disease.blogspot.com/2025/04/wisconsin-dnr-2024-cwd-1786-samples.html

This CWD Study Could Change Deer Hunting FOREVER | The Check Station October 8, 2025 NW Arkansas

NW Arkansas CWD 11:25 minutes;

50% of all deer positive for CWD.

35% of Does are Positive for CWD.

68% Bucks are Positive for CWD.

Most Bucks NW Arkansas that where Tested, are Positive for CWD.

https://m.youtube.com/watch?v=kTicUE-xsQU&t=695s&pp=2AG3BZACAQ%3D%3D

MEMORANDUM

To: Members of the Colorado Parks and Wildlife Commission

From: Dan Prenzlow, Director

Date: April 22, 2022

Subject: Chronic Wasting Disease Update for Parks and Wildlife Commission Chronic wasting disease, a fatal neurological disease found in deer, elk, and moose, is well established in herds throughout much of Colorado. We have detected CWD in 40 of our 54 deer herds, 17 of 42 elk herds, and 2 of 9 moose herds. Disease prevalence (percent infected) is highest in deer and lowest in moose. This disease is always fatal and animals die from the disease within about 2-2.5 years of infection. CWD infection shortens the lifespan of infected animals. If infection rates become too high, CWD can affect a herd’s ability to sustain itself.

Snip…

http://web.archive.org/web/20220609004350/https://cpw.state.co.us/Documents/Commission/2022/May/Item.11-PWC_Memo_CWD_Update_EckertMillerWood_April2022-Matthew_Eckert-DNR.pdf

18% of mule deer in northeastern Montana have deadly chronic wasting disease “In the 2024-25 hunting FWP submitted 9,066 samples for chronic wasting disease testing – the largest number of CWD samples ever collected in a single year. More than 1,100 of these samples were collected by hunters. Of those samples, 335 tested positive for the disease, including 202 white-tailed deer, 127 mule deer and six elk.”

https://billingsgazette.com/outdoors/article_de5278b8-f2e1-11ef-b479-cf42652717a4.html

The effectiveness of harvest for limiting wildlife disease: Insights from 20 years of chronic wasting disease in Wyoming

First published: 21 January 2025

https://doi.org/10.1002/eap.3089

https://esajournals.onlinelibrary.wiley.com/doi/10.1002/eap.3089

https://www.usgs.gov/news/national-news-release/new-study-finds-deer-hunting-can-help-keep-chronic-wasting-disease-check

Since identifying its first cases of CWD in captive deer in the 70s and finding the first wild infected deer in 1985, Wyoming has seen the disease slowly spread throughout the state. CWD has now been documented in members of the deer family in most of Wyoming’s deer hunting areas, with 20% to 40% percent of mule deer affected in some herds. A 2017 study estimated a 21% annual population decline as a result of the fatal disease.

https://freerangeamerican.us/chronic-wasting-disease-wyoming/#:~:text=CWD%20has%20now%20been%20documented,result%20of%20the%20fatal%20disease.

How does CWD impact deer, elk, and moose populations?

Recent research in Wyoming has demonstrated declines in both mule and white-tailed deer populations in deer hunt area 65 due to CWD (see below for citations). These declines are in the core endemic area where prevalence is highest. In areas with lower prevalence, effects of CWD are poorly understood but are considered additive along with other factors that can negatively affect deer populations in Wyoming (i.e. habitat loss, predation, other diseases). The distribution and prevalence of CWD in Wyoming elk is less than that of deer. Currently there are no documented direct population impacts in Wyoming elk from CWD; however, research from Rocky Mountain National Park suggests that CWD could impact elk populations at higher prevalence (13%). While CWD has been found in free ranging moose, there have been few detections, and there is no evidence that CWD is currently having an impact on moose populations.

https://wgfd.wyo.gov/Wildlife-in-Wyoming/More-Wildlife/Wildlife-Disease/Chronic-Wasting-Disease

CWD, Seeing is believing Videos Part 1, Part 2

The below video series is provided by the Mississippi State Deer Lab with many contributing Partners. Click image to find all videos in the series.

Seeing is Believing is a two part documentary film that hopes to increase awareness about chornic wasting disease (CWD). Although most hunters and landowners may never witness a clinically ill animal in an area with high CWD prevalence, the documentary demonstrates how CWD is certainly present, explains why it is a major concern, and how stakeholders are key to managing the disease. Colorado Parks and Wildlife (CPW) developed these films in partnership with the Wyoming Game and Fish Department, Chronic Wasting Disease Alliance, Colorado Department of Agriculture, Animal and Plant Health Inspection Service, and multiple private conservation organizations.

CWD Seeing is believing part 1 Video

https://www.youtube.com/watch?v=fvDTHEwnmO8

CWD Seeing is believing part 2 Video

https://www.youtube.com/watch?v=BbaYYLWewNg

How many deer die from cwd? that dog don't hunt!

15 minute mark video shows sick deer with cwd, and this deer DIED FROM CWD, IT'S DOCUMENTED, commentator says ''so if anyone every tells you, that a deer has never died from CWD, think of this picture, because the Wisconsin Veterinary Lab told us, what when they looked at her sample under a microscope, she was the hottest animal they had ever seen, and that's in terms of the fluorescents that comes off the slide when the look at it, so, a lot of Prion in her system.''

''SCENTS AND LURES, we know that the Prion is shed in urine, and essentially the production of these products is unregulated, we have no idea, you can't tell where they come from, what species are in them, how many animals, how they are processed, there is really no rules about them, so we are concerned it is a way to bring the disease into new areas, and have us fighting on multiple fronts, AND there are zero risk synthetic options that are readily available in stores, so we have ask hunters to switch to zero risk options.''

see much more about 2 hours long...

https://www.youtube.com/watch?v=O3CAI-EwlgM&t=922s

https://www.youtube.com/watch?v=O3CAI-EwlgM

TEXAS BREEDER DEER ESCAPEE WITH CWD IN THE WILD, or so the genetics would show?

OH NO, please tell me i heard this wrong, a potential Texas captive escapee with cwd in the wild, in an area with positive captive cwd herd?

apparently, no ID though. tell me it ain't so please...

23:00 minute mark

''Free Ranging Deer, Dr. Deyoung looked at Genetics of this free ranging deer and what he found was, that the genetics on this deer were more similar to captive deer, than the free ranging population, but he did not see a significant connection to any one captive facility that he analyzed, so we believe, Ahhhhhh, this animal had some captive ahhh, whatnot.''

https://youtu.be/aoPDeGL6mpQ?t=1384

Texas symposium Cwd

https://m.youtube.com/watch?v=nsX4MUWX_d8

Arkansas Cwd

https://m.youtube.com/watch?v=OWpyhEu77hw

Wyoming Cwd 2022 test results

https://m.youtube.com/watch?v=cy_CDnNKQSE

PLoS One. 2016 Aug 30;11(8):e0161127. doi: 10.1371/journal.pone.0161127. eCollection 2016.

Chronic Wasting Disease Drives Population Decline of White-Tailed Deer

We show that a chronic disease that becomes endemic in wildlife populations has the potential to be population-limiting and the strong population-level effects of CWD suggest affected populations are not sustainable at high disease prevalence under current harvest levels.

https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0161127

Friday, December 14, 2012

DEFRA U.K. What is the risk of Chronic Wasting Disease CWD being introduced into Great Britain? A Qualitative Risk Assessment October 2012

snip.....

36% in 2007 (Almberg et al., 2011). In such areas, population declines of deer of up to 30 to 50% have been observed (Almberg et al., 2011). In areas of Colorado, the prevalence can be as high as 30% (EFSA, 2011).

snip.....

The rate of transmission of CWD has been reported to be as high as 30% and can approach 100% among captive animals in endemic areas (Safar et al., 2008). snip.....

https://web.archive.org/web/20170404125557/http://webarchive.nationalarchives.gov.uk/20130822084033/http://www.defra.gov.uk/animal-diseases/files/qra_chronic-wasting-disease-121029.pdf

***> Human CWD TSE PrP, sporadic CJD, or sub-type there from, what if? <***

the problem is, to date, there is NO diagnostic criteria set in stone that would confirm a case of human Cwd, like there was with nvCJD (my Mom died from confirmed hvCJD a rare strain of the infamous sporadic CJDs with new strains mounting, sporadic CJD simply means ‘unknown’, IT DOES NOT MEAN 85%+ SPORADIC CJD IS ALL SPONTANEOUS, that’s all iatrogenic CJD is sporadic CJD, until the iatrogenic event is detected, confirmed, traced back, confirmed, put I to the academic domain, and finally, if your lucky, finally published to the media, and finally the public domain.) sorry, I got off course…but let me perfectly clear here, all science to date shows, Human CWD will not look like New Variant Creutzfeldt Jakob disease nvCJD. CWD to humans will look like some variant of sporadic Creutzfeldt Jakob Disease. And here me out very clearly, and this is from the to TSE Prion Gods themselves, old correspondence from way back during my investigations early BSE nvCJD days…2002

“Also, we do not claim that "no-one has ever been infected with prion disease from eating venison." Our conclusion stating that we found no strong evidence of CWD transmission to humans in the article you quoted or in any other forum is limited to the patients we investigated.”

*** now, let’s see what the authors said about this casual link, personal communications years ago, and then the latest on the zoonotic potential from CWD to humans from the TOKYO PRION 2016 CONFERENCE.

see where it is stated NO STRONG evidence. so, does this mean there IS casual evidence ????

“Our conclusion stating that we found no strong evidence of CWD transmission to humans”

Subject: CWD aka MAD DEER/ELK TO HUMANS ???

Date: September 30, 2002 at 7:06 am PST

From: "Belay, Ermias"

To:

Cc: "Race, Richard (NIH)" ; ; "Belay, Ermias"

Sent: Monday, September 30, 2002 9:22 AM

Subject: RE: TO CDC AND NIH - PUB MED- 3 MORE DEATHS - CWD - YOUNG HUNTERS

Dear Sir/Madam, In the Archives of Neurology you quoted (the abstract of which was attached to your email), we did not say CWD in humans will present like variant CJD.. That assumption would be wrong. I encourage you to read the whole article and call me if you have questions or need more clarification (phone: 404-639-3091).

Also, we do not claim that "no-one has ever been infected with prion disease from eating venison." Our conclusion stating that we found no strong evidence of CWD transmission to humans in the article you quoted or in any other forum is limited to the patients we investigated.

Ermias Belay, M.D. Centers for Disease Control and Prevention

Subject: TO CDC AND NIH - PUB MED- 3 MORE DEATHS - CWD - YOUNG HUNTERS

Sunday, November 10, 2002 6:26 PM .......snip........end..............TSS

-----Original Message-----

From: Sent: Sunday, September 29, 2002 10:15 AM

To: rr26k@nih.gov; rrace@niaid.nih.gov; ebb8@CDC.GOV

Subject: TO CDC AND NIH - PUB MED- 3 MORE DEATHS - CWD - YOUNG HUNTERS

Sunday, November 10, 2002 6:26 PM .......snip........end..............TSS

Thursday, April 03, 2008

A prion disease of cervids: Chronic wasting disease 2008 1: Vet Res. 2008 Apr 3;39(4):41 A prion disease of cervids: Chronic wasting disease Sigurdson CJ.

snip...

*** twenty-seven CJD patients who regularly consumed venison were reported to the Surveillance Center, however there have been no unusual or novel prion subtypes that might indicate the appearance of a new prion strain [7, 41].

snip... full text ;

https://www.vetres.org/articles/vetres/abs/2008/04/v08092/v08092.html

https://chronic-wasting-disease.blogspot.com/2008/04/prion-disease-of-cervids-chronic.html

“regular venison eating associated with a 9 FOLD INCREASE IN RISK OF CJD”

Subject: Re: DEER SPONGIFORM ENCEPHALOPATHY SURVEY & HOUND STUDY

Date: Fri, 18 Oct 2002 23:12:22 +0100

From: Steve Dealler

Reply-To: Bovine Spongiform Encephalopathy Organization: Netscape Online member

To: BSE-L@ …

######## Bovine Spongiform Encephalopathy <BSE-L@UNI-KARLSRUHE.DE> #########

Dear Terry,

An excellent piece of review as this literature is desparately difficult to get back from Government sites. What happened with the deer was that an association between deer meat eating and sporadic CJD was found in about 1993. The evidence was not great but did not disappear after several years of asking CJD cases what they had eaten. I think that the work into deer disease largely stopped because it was not helpful to the UK industry...and no specific cases were reported.

Well, if you dont look adequately like they are in USA currenly then you wont find any!

Steve Dealler

########### http://mailhost.rz.uni-karlsruhe.de/warc/bse-l.html ############

Subject: DEER SPONGIFORM ENCEPHALOPATHY SURVEY & HOUND STUDY

From: "Terry S. Singeltary Sr." <flounder@WT.NET>

Reply To: Bovine Spongiform Encephalopathy <BSE-L@UNI-KARLSRUHE.DE>

Date: Thu, 17 Oct 2002 17:04:51 -0700

snip...

''The association between venison eating and risk of CJD shows similar pattern, with regular venison eating associated with a 9 FOLD INCREASE IN RISK OF CJD (p = 0.04).''

CREUTZFELDT JAKOB DISEASE SURVEILLANCE IN THE UNITED KINGDOM THIRD ANNUAL REPORT AUGUST 1994

snip...see full report ;

http://web.archive.org/web/20090506050043/http://www.bseinquiry.gov.uk/files/yb/1994/08/00004001.pdf

http://web.archive.org/web/20090506050007/http://www.bseinquiry.gov.uk/files/yb/1994/10/00003001.pdf

http://web.archive.org/web/20090506050244/http://www.bseinquiry.gov.uk/files/yb/1994/07/00001001.pdf

Stephen Dealler is a consultant medical microbiologist deal@airtime.co.uk BSE Inquiry Steve Dealler Management In Confidence BSE: Private Submission of Bovine Brain Dealler

snip...end

########### http://mailhost.rz.uni-karlsruhe.de/warc/bse-l.html ############

*** These results would seem to suggest that CWD does indeed have zoonotic potential, at least as judged by the compatibility of CWD prions and their human PrPC target. Furthermore, extrapolation from this simple in vitro assay suggests that if zoonotic CWD occurred, it would most likely effect those of the PRNP codon 129-MM genotype and that the PrPres type would be similar to that found in the most common subtype of sCJD (MM1).***

http://www.tandfonline.com/doi/full/10.4161/pri.28124?src=recsys

http://www.tandfonline.com/doi/pdf/10.4161/pri.28124?needAccess=true

https://wwwnc.cdc.gov/eid/article/20/1/13-0858_article

So, this is what we leave our children and grandchildren?

CDC CWD TSE Prion Update 2025

KEY POINTS

Chronic wasting disease affects deer, elk and similar animals in the United States and a few other countries.

The disease hasn't been shown to infect people.

However, it might be a risk to people if they have contact with or eat meat from animals infected with CWD.

https://www.cdc.gov/chronic-wasting/about/index.html

Prions in Muscles of Cervids with Chronic Wasting Disease, Norway

Volume 31, Number 2—February 2025

Research

Prions in Muscles of Cervids with Chronic Wasting Disease, Norway

Snip…

In summary, the results of our study indicate that prions are widely distributed in peripheral and edible tissues of cervids in Norway, including muscles. This finding highlights the risk of human exposure to small amounts of prions through handling and consuming infected cervids.

Appendix

https://wwwnc.cdc.gov/eid/article/31/2/24-0903-app1.pdf

https://wwwnc.cdc.gov/eid/article/31/2/24-0903_article

Volume 31, Number 2—February 2025

Dispatch

Detection of Chronic Wasting Disease Prions in Raw, Processed, and Cooked Elk Meat, Texas, USA

Snip…

Of note, our data show that exposure to high temperatures used to cook the meat increased the availability of prions for in vitro amplification. Considering the potential implications in food safety and public health, we believe that the findings described in this study warrant further research. Our results suggest that although the elk meat used in this study resisted different manipulations involved in subsequent consumption by humans, their zoonotic potential was limited. Nevertheless, even though no cases of CWD transmission to human have been reported, the potential for human infection is still unclear and continued monitoring for zoonotic potential is warranted.

https://wwwnc.cdc.gov/eid/article/31/2/24-0906_article

Detection of chronic wasting disease prions in processed meats

Results: Our results show positive prion detection in all the samples analyzed using deer and elk substrates. Surprisingly, cooked meats displayed increased seeding activities. This data suggests that CWD-prions are available to people even after meats are processed and cooked.

Conclusions: These results suggest CWD prions are accessible to humans through meats, even after processing and cooking. Considering the fact that these samples were collected from already processed specimens, the availability of CWD prions to humans is probably underestimated.

"Our results show positive prion detection in all the samples analyzed using deer and elk substrates. Surprisingly, cooked meats displayed increased seeding activities."

Meeting-book-final-version prion 2023 Prion 2023 Congress Organizing Committee and the NeuroPrion Association, we invite you to join us for the International Conference Prion2023 from 16-20 October 2023 in Faro, Portugal.

https://prion2023.org/wp-content/uploads/2023/10/Meeting-book-final-version2.pdf

https://web.archive.org/web/20250828201533/https://prion2023.org/wp-content/uploads/2023/10/Meeting-book-final-version2.pdf

https://www.researchgate.net/profile/Syed-Zahid-Shah/publication/378314391_Meeting-book-final-version_prion_2023/links/65d44dad28b7720cecdca95f/Meeting-book-final-version-prion-2023.pdf

DETECTION OF CHRONIC WASTING DISEASE PRIONS IN PROCESSED MEATS.

In this study, we analyzed different processed meats derived from a pre-clinical, CWD-positive free-ranging elk. Products tested included filets, sausages, boneless steaks, burgers, ham steaks, seasoned chili meats, and spiced meats. CWD-prion presence in these products were assessed by PMCA using deer and elk substrates. Our results show positive prion detection in all products. To confirm the resilience of CWD-prions to traditional cooking methods, we grilled and boiled the meat products and evaluated them for any remnant PMCA seeding activity. Results confirmed the presence of CWD-prions in these meat products suggesting that infectious particles may still be available to people even after cooking. Our results strongly suggest ongoing human exposure to CWD-prions and raise significant concerns of zoonotic transmission through ingestion of CWD contaminated meat products.

Products tested included filets, sausages, boneless steaks, burgers, ham steaks, seasoned chili meats, and spiced meats.

CWD-prion presence in these products were assessed by PMCA using deer and elk substrates.

Our results show positive prion detection in all products.

Results confirmed the presence of CWD-prions in these meat products suggesting that infectious particles may still be available to people even after cooking.

Our results strongly suggest ongoing human exposure to CWD-prions and raise significant concerns of zoonotic transmission through ingestion of CWD contaminated meat products.

https://intcwdsympo.files.wordpress.com/2023/06/final-agenda-with-abstracts.pdf?force_download=true

Transmission of prion infectivity from CWD-infected macaque tissues to rodent models demonstrates the zoonotic potential of chronic wasting disease.

Further passage to cervidized mice revealed transmission with a 100% attack rate.

Our findings demonstrate that macaques, considered the best model for the zoonotic potential of prions, were infected upon CWD challenge, including the oral one.

The disease manifested as atypical in macaques and initial transgenic mouse transmissions, but with infectivity present at all times, as unveiled in the bank vole model with an unusual tissue tropism.

Epidemiologic surveillance of prion disease among cervid hunters and people likely to have consumed venison contaminated with chronic wasting disease

=====

https://intcwdsympo.files.wordpress.com/2023/06/final-agenda-with-abstracts.pdf?force_download=true

Fortuitous generation of a zoonotic cervid prion strain

Aims: Whether CWD prions can infect humans remains unclear despite the very substantial scale and long history of human exposure of CWD in many states or provinces of USA and Canada. Multiple in vitro conversion experiments and in vivo animal studies indicate that the CWD-to-human transmission barrier is not unbreakable. A major long-term public health concern on CWD zoonosis is the emergence of highly zoonotic CWD strains. We aim to address the question of whether highly zoonotic CWD strains are possible.

Materials and Methods: We inoculated several sCJD brain samples into cervidized transgenic mice (Tg12), which were intended as negative controls for bioassays of brain tissues from sCJD cases who had potentially been exposed to CWD. Some of the Tg12mice became infected and their brain tissues were further examined by Western blot as well as serial passages in humanized or cervidized mice.

Results: Passage of sCJDMM1 in transgenic mice expressing elk PrP (Tg12) resulted in a “cervidized” CJD strain that we termed CJDElkPrP. We observed 100% transmission of the original CJDElkPrP in transgenic mice expressing human PrP. We passaged CJDElkPrP two more times in the Tg12mice. We found that such second and third passage CJDElkPrP prions retained 100% transmission rate in the humanized mice, despite that the natural elk CWD isolates and CJDElkPrP share the same elk PrP sequence. In contrast, we and others found zero or poor transmission of natural elk CWD isolates in humanized mice.

Conclusions: Our data indicate that highly zoonotic cervid prion strains are not only possible but also can retain zoonotic potential after serial passages in cervids, suggesting a very significant and serious long-term risk of CWD zoonosis given that the broad and continuing spread of CWD prions will provide fertile grounds for the emergence of zoonotic CWD strains over time.

https://prion2023.org/wp-content/uploads/2023/10/Meeting-book-final-version2.pdf 

https://web.archive.org/web/20250828201533/https://prion2023.org/wp-content/uploads/2023/10/Meeting-book-final-version2.pdf

https://www.researchgate.net/profile/Syed-Zahid-Shah/publication/378314391_Meeting-book-final-version_prion_2023/links/65d44dad28b7720cecdca95f/Meeting-book-final-version-prion-2023.pdf

Transmission of cervid prions to humanized mice demonstrates the zoonotic potential of CWD

Samia Hannaoui1 · Irina Zemlyankina1 · Sheng Chun Chang1 · Maria Immaculata Arifn1 · Vincent Béringue2 · Debbie McKenzie3 · Hermann M. Schatzl1 · Sabine Gilch1

Received: 24 May 2022 / Revised: 5 August 2022 / Accepted: 7 August 2022

© The Author(s) 2022

Abstract

Prions cause infectious and fatal neurodegenerative diseases in mammals. Chronic wasting disease (CWD), a prion disease of cervids, spreads efficiently among wild and farmed animals. Potential transmission to humans of CWD is a growing concern due to its increasing prevalence. Here, we provide evidence for a zoonotic potential of CWD prions, and its probable signature using mice expressing human prion protein (PrP) as an infection model. Inoculation of these mice with deer CWD isolates resulted in atypical clinical manifestation with prion seeding activity and efficient transmissible infectivity in the brain and, remarkably, in feces, but without classical neuropathological or Western blot appearances of prion diseases. Intriguingly, the protease-resistant PrP in the brain resembled that found in a familial human prion disease and was transmissible upon second passage. Our results suggest that CWD might infect humans, although the transmission barrier is likely higher compared to zoonotic transmission of cattle prions. Notably, our data suggest a different clinical presentation, prion signature, and tissue tropism, which causes challenges for detection by current diagnostic assays. Furthermore, the presence of infectious prions in feces is concerning because if this occurs in humans, it is a source for human-to-human transmission. These findings have strong implications for public health and CWD management.

Keywords Chronic wasting disease · CWD · Zoonotic potential · Prion strains · Zoonotic prions

HIGHLIGHTS OF THIS STUDY

================================

Our results suggest that CWD might infect humans, although the transmission barrier is likely higher compared to zoonotic transmission of cattle prions. Notably, our data suggest a different clinical presentation, prion signature, and tissue tropism, which causes challenges for detection by current diagnostic assays. Furthermore, the presence of infectious prions in feces is concerning because if this occurs in humans, it is a source for human-to-human transmission. These findings have strong implications for public health and CWD management.

In this study, we evaluated the zoonotic potential of CWD using a transgenic mouse model overexpressing human M129-PrPC (tg650 [12]). We inoculated tg650mice intracerebrally with two deer CWD isolates, Wisc-1 and 116AG [22, 23, 27, 29]. We demonstrate that this transgenic line was susceptible to infection with CWD prions and displayed a distinct leading clinical sign, an atypical PrPSc signature and unusual fecal shedding of infectious prions. Importantly, these prions generated by the human PrP transgenic mice were transmissible upon passage. Our results are the first evidence of a zoonotic risk of CWD when using one of the most common CWD strains, Wisc-1/CWD1 for infection. We demonstrated in a human transgenic mouse model that the species barrier for transmission of CWD to humans is not absolute. The fact that its signature was not typical raises the questions whether CWD would manifest in humans as a subclinical infection, whether it would arise through direct or indirect transmission including an intermediate host, or a silent to uncovered human-to-human transmission, and whether current detection techniques will be suffcient to unveil its presence.

Our findings strongly suggest that CWD should be regarded as an actual public health risk. Here, we use humanized mice to show that CWD prions can cross the species barrier to humans, and remarkably, infectious prions can be excreted in feces.

Our results indicate that if CWD crosses the species-barrier to humans, it is unlikely to resemble the most common forms of human prion diseases with respect to clinical signs, tissue tropism and PrPSc signature. For instance, PrPSc in variable protease-sensitive prionopathy (VPSPr), a sporadic form of human prion disease, and in the genetic form Gerstmann-Sträussler-Scheinker syndrome (GSS) is defined by an atypical PK-resistant PrPSc fragment that is non-glycosylated and truncated at both C- and N-termini, with a molecular weight between 6 and 8 kDa [24, 44–46]. These biochemical features are unique and distinctive from PrPSc (PrP27-30) found in most other human or animal prion disease. The atypical PrPSc signature detected in brain homogenate of tg650 mice #321 (1st passage) and #3063 (2nd passage), and the 7–8 kDa fragment (Figs. 2, 4) are very similar to that of GSS, both in terms of migration profile and the N-terminal cleavage site.

CWD in humans might remain subclinical but with PrPSc deposits in the brain with an unusual morphology that does not resemble the patterns usually seen in different prion diseases (e.g., mouse #328; Fig. 3), clinical with untraceable abnormal PrP (e.g., mouse #327) but still transmissible and uncovered upon subsequent passage (e.g., mouse #3063; Fig. 4), or prions have other reservoirs than the usual ones, hence the presence of infectivity in feces (e.g., mouse #327) suggesting a potential for human-to-human transmission and a real iatrogenic risk that might be unrecognizable.

“suggesting a potential for human-to-human transmission and a real iatrogenic risk that might be unrecognizable.”

=================================

Supplementary Information The online version contains supplementary material available at

https://doi.org/10.1007/s00401-022-02482-9

snip...see full text;

https://link.springer.com/article/10.1007/s00401-022-02482-9

https://link.springer.com/content/pdf/10.1007/s00401-022-02482-9.pdf

Macaque tissues to rodent models demonstrates the zoonotic potential of chronic wasting disease.

Samia Hannaoui1,2, Ginny Cheng1,2, Wiebke Wemheuer3, Walter Schulz-Schaeffer3, Sabine Gilch1,2, Hermann Schatzl1,2 1University of Calgary, Calgary, Canada. 2Calgary Prion Research Unit, Calgary, Canada. 3Institute of Neuropathology, Medical Faculty, Saarland University, Homburg/Saar, Germany

Snip…

***> Further passage to cervidized mice revealed transmission with a 100% attack rate.

***> Our findings demonstrate that macaques, considered the best model for the zoonotic potential of prions, were infected upon CWD challenge, including the oral one.

****> The disease manifested as atypical in macaques and initial transgenic mouse transmissions, but with infectivity present at all times, as unveiled in the bank vole model with an unusual tissue tropism.

***> Epidemiologic surveillance of prion disease among cervid hunters and people likely to have consumed venison contaminated with chronic wasting disease

=====

https://intcwdsympo.files.wordpress.com/2023/06/final-agenda-with-abstracts.pdf?force_download=true

Transmission of Cervid Prions to Humanized Mice Demonstrates the Zoonotic Potential of CWD

Samia Hannaouia, Irina Zemlyankinaa, Sheng Chun Changa, Maria Immaculata Arifina, Vincent Béringueb, Debbie McKenziec, Hermann M. Schatzla, and Sabine Gilcha

Results: Here, we provide the strongest evidence supporting the zoonotic potential of CWD prions, and their possible phenotype in humans. Inoculation of mice expressing human PrPCwith deer CWD isolates (strains Wisc-1 and 116AG) resulted in atypical clinical manifestations in > 75% of the mice, with myoclonus as leading clinical sign. Most of tg650brain homogenates were positive for seeding activity in RT-QuIC. Clinical disease and presentation was transmissible to tg650mice and bank voles. Intriguingly, protease-resistant PrP in the brain of tg650 mice resembled that found in a familial human prion disease and was transmissible upon passage. Abnormal PrP aggregates upon infection with Wisc-1 were detectable in thalamus, hypothalamus, and midbrain/pons regions.

Unprecedented in human prion disease, feces of CWD-inoculated tg650 mice harbored prion seeding activity and infectious prions, as shown by inoculation of bank voles and tg650 with fecal homogenates.

Conclusions: This is the first evidence that CWD can infect humans and cause disease with a distinctive clinical presentation, signature, and tropism, which might be transmissible between humans while current diagnostic assays might fail to detect it. These findings have major implications for public health and CWD-management.

https://www.tandfonline.com/doi/full/10.1080/19336896.2022.2091286

18. Zoonotic potential of moose-derived chronic wasting disease prions after adaptation in intermediate species

Tomás Barrioa, Jean-Yves Doueta, Alvina Huora, Séverine Lugana, Naïma Arona, Hervé Cassarda, Sylvie L. Benestadb, Juan Carlos Espinosac, Juan María Torresc, Olivier Andréolettia

aUnité Mixte de Recherche de l’Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement 1225 Interactions Hôtes-Agents Pathogènes, École Nationale Vétérinaire de Toulouse, 31076 Toulouse, France; bNorwegian Veterinary Institute, P.O. Box 64, NO-1431 Ås, Norway; cCentro de Investigación en Sanidad Animal (CISA-INIA), 28130, Valdeolmos, Madrid, Spain

Aims: Chronic wasting disease (CWD) is an emerging prion disease in Europe. To date, cases have been reported in three Nordic countries and in several species, including reindeer (Rangifer tarandus), moose (Alces alces) and red deer (Cervus elaphus). Cumulating data suggest that the prion strains responsible for the European cases are distinct from those circulating in North America. The biological properties of CWD prions are still poorly documented, in particular their spillover and zoonotic capacities. In this study, we aimed at characterizing the interspecies transmission potential of Norwegian moose CWD isolates.

Materials and Methods: For that purpose, we performed experimental transmissions in a panel of transgenic models expressing the PrPC sequence of various species.

Results: On first passage, one moose isolate propagated in the ovine PrPC-expressing model (Tg338). After adaptation in this host, moose CWD prions were able to transmit in mice expressing either bovine or human PrPC with high efficacy.

Conclusions: These results suggest that CWD prions can acquire enhanced zoonotic properties following adaptation in an intermediate species.

Funding

Grant number: AAPG2020 EU-CWD, ICRAD2020 TCWDE, NRC2022 NorCWD

Acknowledgement

https://www.tandfonline.com/doi/full/10.1080/19336896.2024.2424058

“ After adaptation in this host, moose CWD prions were able to transmit in mice expressing either bovine or human PrPC with high efficacy.”

While no one was watching: Tenuous status of CDC prion unit, risk of CWD to people worry scientists

Mary Van Beusekom, MS Today at 9:15 a.m.

Chronic Wasting Disease BSE CWD zone deer disposal site Lorie Shaull / Flickr cc

Nine months ago, Janie Johnston, 73, left her home in the Chicago suburbs to drive to her doctor's office for routine care. She made it as far as the side of the street opposite the clinic but couldn't figure out how to get there, so she returned home, where she struggled to remember the abbreviation "GPS."

That was the first sign that something was seriously wrong. Soon, the semi-retired geologist couldn't speak in full sentences or feed herself. Within 2 months, the woman who had been reviewing proposals for the National Science Foundation in the weeks leading up to symptom onset was dead of a terrifying neurological disease her family had never heard of: Creutzfeldt-Jakob disease (CJD).

CWD may cause CJD-like disease if it infects people Rather than being genetic or acquired, Johnston's CJD developed when normal prions in her brain spontaneously began misfolding. The abnormal prions accumulated rather than being shed, triggering confusion and fatigue that doctors initially mistook for stroke, meningitis, or alcohol withdrawal. The disease usually occurs in older adults.

Seeing what my mom went through, I do not want anyone else to have to experience that, nor their family members. Kristal Enter

While no one is certain, experts think that another always-fatal prion disease—this one currently known to occur only in cervids such as deer, moose, and elk—may behave the same way if it should jump the species barrier and infect people.

Chronic wasting disease (CWD) has been decimating cervid populations throughout North America since it was first diagnosed in a captive Colorado mule deer in 1967. While mitigation measures such as hunting may help slow its spread, it can't be stopped.

This is because cervids are ubiquitous and free ranging, the interval from infection to symptom onset can take years, and prions spread easily from animal to animal and through environmental contamination, which can persist for years.

Johnston's daughter, Kristal Enter, 39, a fundraiser in Boston, is familiar with CWD and its potential implications for human health. "Seeing what my mom went through, I do not want anyone else to have to experience that, nor their family members," she told CIDRAP News. "The more we're on top of chronic wasting disease and thinking about it, the better."

But the frightening thing is that, for well over a month during the recent US government shutdown, no one was watching the human disease landscape for CWD, a highly infectious disease with no treatment or cure.

If cases slip by, it will be too late Nine days after the government shutdown began, all four staff members of the Centers for Disease Control and Prevention's (CDC's) National Center for Emerging and Zoonotic Infectious Diseases Prion and Public Health Office were sent home after receiving reduction-in-force (RIF) notices. While the end of the shutdown led all four to be reinstated through at least January, layoffs after that time are possible.

Within the past few months, two other researchers who had been part of the team also had to be let go after their fellowship contracts weren't renewed, per the administration's policy of blocking contract renewals.

The prion unit, which monitors the nation for human prion diseases, is part of the Division of High-Consequence Pathogens and Pathology. It launched in the mid-1990s in response to the outbreak of bovine spongiform encephalopathy (BSE, or "mad cow disease") in UK cattle. BSE prions were inadvertently consumed by people who ate contaminated beef, causing the human form of BSE, variant CJD (vCJD). All infected people—more than 230—died.

The initial goal of the Prion and Public Health Office was to watch for any cases of vCJD in the US population. Since then, its focus has expanded to include advising hospitals on how to prevent and respond to prion contamination of instruments used in neurosurgery (prions are resistant to many usual sterilization methods), as well as working with state health departments on disease surveillance. Unit members also answer questions from the public.

Today, as CWD continues its inexorable march across the landscape, exposing more and more people, the prion unit's priority is conducting surveillance for signs of a CWD species jump into high-risk people such as hunters. Without this expertise, no one will be able to evaluate whether a suspected case of CWD prion transmission to humans is likely from an animal.

The prion unit has launched several epidemiologic studies in collaboration with multiple states to look at whether more hunters are dying of prion diseases than would be expected.

Janie Johnston Janie Johnston / Courtesy of Kristal Enter As an example of the unit's work, last spring, a cluster of CJD cases in Oregon was widely conjectured to be linked to CWD. Such cases require autopsy and an epidemiologic investigation to determine whether CWD was involved and, if so, what kind of public health measures are needed. The prion unit shared ideas and strategy with the Oregon state health department in this investigation, which, thankfully, found no link.

But experts say that without anyone looking for these deviations from normal—particularly given that signs of illness may take years to appear—cases could easily go unnoticed, and it will be too late to implement public health measures that could mitigate some of these consequences.

Lawrence Schonberger, MD, MPH, retired chief of the Prion and Public Health Office, said that, as was the situation with BSE, CWD containment efforts must continue. "Unlike with mad cow disease, however, these efforts to date have not been successful," he said. Surveillance and research "should continue to help people recognize any emerging risk to humans from this agent now and in the future, when this agent's pathogenicity [ability to cause disease] may change."

'Worst time to get rid of such a division' Brian Appleby, MD, is director of the National Prion Disease Pathology Surveillance Center at Case Western University, which conducts diagnostic testing for human prion diseases and conducted Johnston's autopsy. The CDC funds the center, which collaborates with the Prion and Public Health Office on public health efforts and research projects.

When you don't have a neutral party investigating these things or doing neuropathology to confirm or refute those things, you really have no idea what's going on in the public health space. Brian Appleby, MD

If the CDC prion unit were eliminated, "no one would be looking at prion disease," Appleby said. "We wouldn't be able to tell if we have an increase in cases or where they're going or coming from. And when you don't have a neutral party investigating these things or doing neuropathology to confirm or refute those things, you really have no idea what's going on in the public health space."

And with the threat of CWD, "this is probably the worst time to get rid of such a division," he added.

While there have been no stated plans to eliminate the unit, history hints that its continued existence may be in jeopardy. In fact, it was removed from President Donald Trump's budget during both of his administrations, before the House of Representatives and Senate reinstated it, Appleby said.

In the first Trump administration, report language stated that human prion surveillance is redundant because cattle are now screened for BSE, and the National Institutes of Health cover research, said Appleby, who refuted the assertions.

"Part of the reason why we are a safe export country for beef is not just the cattle surveillance for BSE, but the human surveillance for variant CJD," he said, adding that monitoring is a separate function from research. "When we were removed from the president's budget this time around, there was no report language, so we have no signal to know why."

Always 'one step behind' Debbie Yobs, president and executive director of the CJD Foundation, a patient-advocacy organization that works with Appleby's center to provide medical lectures, support groups, and other programs, emphasized the importance of sustained surveillance. "You can't have gaps in monitoring a deadly disease like prion disease," she said.

It's like combining symptoms of Alzheimer's, Parkinson's, and ALS [amyotrophic lateral sclerosis, or Lou Gehrig's disease] and then speeding it all up. Debbie Yobs

CJD is devastating for patients and families, said Yobs, whose husband, Patrick, died at age 45 of the less common, genetic form of the disease. "It's like combining symptoms of Alzheimer's, Parkinson's, and ALS [amyotrophic lateral sclerosis, or Lou Gehrig's disease] and then speeding it all up," she added. "There's no definitive diagnosis except through autopsy."

Indeed, Enter called her family's ordeal "unreal," because although Johnston's case was typical of a sporadic case, CJD affects only about 500 to 600 people in the United States each year, per the CDC. At the same time as the family was grieving, they were trying to learn how hospice staff could best manage Johnston's symptoms, which none of them had dealt with before.

"It becomes incumbent upon the family members to become the experts to guide the care," she said. "What they say about CJD is that every day is another new symptom or new complication to have to try to address. And you always feel like you're one step behind."

https://www.cidrap.umn.edu/chronic-wasting-disease/while-no-one-was-watching-tenuous-status-cdc-prion-unit-risk-cwd-people

“While no one was watching: Tenuous status of CDC prion unit, risk of CWD to people worry scientists”

FRIDAY, NOVEMBER 21, 2025

While no one was watching: Tenuous status of CDC prion unit, risk of CWD to people worry scientists

https://chronic-wasting-disease.blogspot.com/2025/11/while-no-one-was-watching-tenuous.html

2004

Jeff Swann and his Mom, cwd link... sporadic CJD?, CBC NEWS Jeff Schwan sCJD, CWD, and Professor Aguzzi on BSE and sporadic CJD

????: CBCnews

https://histodb15.usz.ch/pages/Images/videos/video-004/video-004.html

2004

April 22, 2004, 10:30 AM CDT Guests: Patrick Singh, Terry Schwan, Janet Skarbek, Bill Fielding (BEGIN VIDEOTAPE) ANNOUNCER: DEBORAH NORVILLE TONIGHT.

https://www.nbcnews.com/id/wbna4806886

1997-11-10: Panorama - The British disease

https://histodb15.usz.ch/pages/Images/videos/video-009/video-009.html

Two Hunters from the Same Lodge Afflicted with Sporadic CJD: Is Chronic Wasting Disease to Blame?

(P7-13.002) Jonathan Trout, Matthew Roberts, Michel Tabet, Eithan Kotkowski, and Sarah HornAUTHORS INFO & AFFILIATIONS April 9, 2024 issue 102 (17_supplement_1) https://doi.org/10.1212/WNL.0000000000204407

Abstract Publication History Information & Authors Metrics & Citations Share Abstract

Objective:

This study presents a cluster of Creutzfeldt-Jakob disease (CJD) cases after exposure to chronic wasting disease (CWD)-infected deer, suggestive of potential prion transmission from CWD-infected deer to humans.

Background:

CJD is a rapidly progressive central nervous system disorder caused by misfolded prion proteins. CWD, a prion disease prevalent in North American deer, has raised concerns due to its possible link to CJD. Although no conclusive evidence of cross-species prion transmission exists, vigilance for such cases is crucial for public health.

Design/Methods:

Not applicable.

Results:

In 2022, a 72-year-old man with a history of consuming meat from a CWD-infected deer population presented with rapid-onset confusion and aggression. His friend, who had also eaten venison from the same deer population, recently died of CJD, raising concerns about a potential link between CWD and human prion disease. Despite aggressive symptomatic treatment of seizures and agitation, the patient’s condition deteriorated and he died within a month of initial presentation. The diagnosis was confirmed postmortem as sporadic CJD with homozygous methionine at codon 129 (sCJDMM1). The patient’s history, including a similar case in his social group, suggests a possible novel animal-to-human transmission of CWD. Based on non-human primate and mouse models, cross-species transmission of CJD is plausible. Due to the challenge of distinguishing sCJDMM1 from CWD without detailed prion protein characterization, it is not possible to definitively rule out CWD in these cases. Although causation remains unproven, this cluster emphasizes the need for further investigation into the potential risks of consuming CWD-infected deer and its implications for public health.

Conclusions:

Clusters of sporadic CJD cases may occur in regions with CWD-confirmed deer populations, hinting at potential cross-species prion transmission. Surveillance and further research are essential to better understand this possible association.

Disclosure: Mr. Trout has nothing to disclose. Dr. Roberts has nothing to disclose. Dr. Tabet has nothing to disclose. Dr. Kotkowski has nothing to disclose. Dr. Horn has received personal compensation in the range of $500-$4,999 for serving as a Consultant for Cala Trio. The institution of Dr. Horn has received research support from Alzheimer's Association.

https://www.neurology.org/doi/10.1212/WNL.0000000000204407

FRIDAY, NOVEMBER 21, 2025

***> While no one was watching: Tenuous status of CDC prion unit, risk of CWD to people worry scientists

https://chronic-wasting-disease.blogspot.com/2025/11/while-no-one-was-watching-tenuous.html 

iatrogenic TSE/CWD, my greatest fear, here’s why…

one of the old studies that has always stuck out in my mind, one that the late great Dr. Gibbs, Gajdusek, et al did way back, and to this day is still amazes me...

*** Transmission of Creutzfeldt-Jakob disease to a chimpanzee by electrodes contaminated during neurosurgery ***

Gibbs CJ Jr, Asher DM, Kobrine A, Amyx HL, Sulima MP, Gajdusek DC.

Laboratory of Central Nervous System Studies, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892. Stereotactic multicontact electrodes used to probe the cerebral cortex of a middle aged woman with progressive dementia were previously implicated in the accidental transmission of Creutzfeldt-Jakob disease (CJD) to two younger patients. The diagnoses of CJD have been confirmed for all three cases. More than two years after their last use in humans, after three cleanings and repeated sterilisation in ethanol and formaldehyde vapour, the electrodes were implanted in the cortex of a chimpanzee. Eighteen months later the animal became ill with CJD. This finding serves to re-emphasise the potential danger posed by reuse of instruments contaminated with the agents of spongiform encephalopathies, even after scrupulous attempts to clean them.

http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=8006664&dopt=Abstract

France issues moratorium on prion research after fatal brain disease strikes two lab workers

By Barbara CasassusJul. 28, 2021 , 4:35 AM

PARIS—Five public research institutions in France have imposed a 3-month moratorium on the study of prions—a class of misfolding, infectious proteins that cause fatal brain diseases—after a retired lab worker who handled prions in the past was diagnosed with Creutzfeldt-Jakob disease (CJD), the most common prion disease in humans. An investigation is underway to find out whether the patient, who worked at a lab run by the National Research Institute for Agriculture, Food and Environment (INRAE), contracted the disease on the job.

If so, it would be the second such case in France in the past few years. In June 2019, an INRAE lab worker named Émilie Jaumain died at age 33, 10 years after pricking her thumb during an experiment with prion-infected mice. Her family is now suing INRAE for manslaughter and endangering life; her illness had already led to tightened safety measures at French prion labs.

The aim of the moratorium, which affects nine labs, is to “study the possibility of a link with the [new patient’s] former professional activity and if necessary to adapt the preventative measures in force in research laboratories,” according to a joint press release issued by the five institutions yesterday.

“This is the right way to go in the circumstances,” says Ronald Melki, a structural biologist at a prion lab jointly operated by the French national research agency CNRS and the French Alternative Energies and Atomic Energy Commission (CEA). “It is always wise to ask questions about the whole working process when something goes wrong.” "The occurrence of these harsh diseases in two of our scientific colleagues clearly affects the whole prion community, which is a small 'familial' community of less than 1000 people worldwide," Emmanuel Comoy, deputy director of CEA's Unit of Prion Disorders and Related Infectious Agents, writes in an email to Science. Although prion research already has strict safety protocols, "it necessarily reinforces the awareness of the risk linked to these infectious agents," he says.

In Jaumain’s case, there is little doubt she was infected on the job, according to a paper published in The New England Journal of Medicine (NEJM) in 2020. She had variant CJD (vCJD), a form typically caused by eating beef contaminated with bovine spongiform encephalopathy (BSE), or mad cow disease. But Europe’s BSE outbreak ended after 2000 and vCJD virtually disappeared; the chance that someone of Jaumain’s age in France would contract food-borne vCJD is “negligible or non-existent,” according to the paper.

A scientist with inside knowledge says the new patient, a woman who worked at INRAE’s Host-Pathogen Interactions and Immunity group in Toulouse, is still alive. French authorities were apparently alerted to her diagnosis late last week. The press release suggests it’s not yet clear whether the new case is vCJD or “classic” CJD, which is not known to be caused by prions from animals. Classic CJD strikes an estimated one person per million. Some 80% of cases are sporadic, meaning they have no known cause, but others are genetic or contracted from infected human tissues during transplantations. The two types of CJD can only be distinguished through a postmortem examination of brain tissue.

Lab infections are known to occur with many pathogens, but exposure to CJD-causing prions is unusually risky because there are no vaccines or treatments and the condition is universally fatal. And whereas most infections reveal themselves within days or weeks, CJD’s average incubation period is about 10 years.

For Jaumain, who worked at INRAE’s Molecular Virology and Immunology Unit in Jouy-en-Josas, outside Paris, that long period of uncertainty began on 31 May 2010, when she stabbed her left thumb with a curved forceps while cleaning a cryostat—a machine that can cut tissues at very low temperatures—that she used to slice brain sections from transgenic mice infected with a sheep-adapted form of BSE. She pierced two layers of latex gloves and drew blood. “Émilie started worrying about the accident as soon as it had happened, and mentioned it to every doctor she saw,” says her widower, Armel Houel.

In November 2017, Jaumain developed a burning pain in her right shoulder and neck that worsened and spread to the right half of her body over the following 6 months, according to the NEJM paper. In January 2019, she became depressed and anxious, suffering memory impairment and hallucinations. “It was a descent into hell,” Houel says. She was diagnosed with “probable vCJD” in mid-March of that year and died 3 months later. A postmortem confirmed the diagnosis.

“The occurrence of these harsh diseases in two of our scientific colleagues clearly affects the whole prion community.” Emmanuel Comoy, French Alternative Energies and Atomic Energy Commission

INRAE only recently admitted the likely link between Jaumain’s illness and the accident. “We recognize, without ambiguity, the hypothesis of a correlation between Emilie Jaumain-Houel’s accident … and her infection with vCJD,” INRAE chair and CEO Philippe Mauguin wrote in a 24 June letter to an association created by friends and colleagues to publicize Jaumain’s case and lobby for improvements in lab safety. (Science has obtained a copy of the letter, which has not been made public.)

Jaumain’s family has filed both criminal charges and an administrative suit against INRAE, alleging a range of problems at Jaumain’s lab. She had not been trained in handling dangerous prions or responding to accidents and did not wear both metal mesh and surgical gloves, as she was supposed to, says Julien Bensimhon, the family’s lawyer. The thumb should have been soaked in a bleach solution immediately, which did not happen, Bensimhon adds.

Independent reports by a company specializing in occupational safety and by government inspectors have found no safety violations at the lab; one of them said there was a “strong culture” of risk management. (Bensimhon calls the reports “biased.”)

The government inspectors’ report concluded that Jaumain’s accident was not unique, however. There had been at least 17 accidents among the 100 or so scientists and technicians in France working with prions in the previous decade, five of whom stabbed or cut themselves with contaminated syringes or blades. Another technician at the same lab had a fingerprick accident with prions in 2005, but has not developed vCJD symptoms so far, Bensimhon says. “It is shocking that no precautionary measures were taken then to ensure such an accident never happened again,” he says.

In Italy, too, the last person to die of vCJD, in 2016, was a lab worker with exposure to prion-infected brain tissue, according to last year’s NEJM paper, although an investigation did not find evidence of a lab accident. That patient and the lab they worked at have not been identified.

After Jaumain’s diagnosis, “We contacted all the research prion labs in France to suggest they check their safety procedures and remind staff about the importance of respecting them,” says Stéphane Haïk, a neuroscientist at the Paris Brain Institute at Pitié-Salpêtrière Hospital who helped diagnose Jaumain and is the corresponding author on the paper. Many labs tightened procedures, according to the government inspectors' report, for instance by introducing plastic scissors and scalpels, which are disposable and less sharp, and bite and cut-resistant gloves. A team of experts from the five research agencies is due to submit proposals for a guide to good practice in prion research to the French government at the end of this year.

The scientific community has long recognized that handling prions is dangerous and an occupational risk for neuropathologists, says neuropathologist Adriano Aguzzi of the University of Zurich. Aguzzi declined to comment on the French CJD cases, but told Science his lab never handles human or bovine prions for research purposes, only for diagnostics. “We conduct research only on mouse-adapted sheep prions, which have never been shown to be infectious to humans,” Aguzzi says. In a 2011 paper, his team reported that prions can spread through aerosols, at least in mice, which “may warrant re-thinking on prion biosafety guidelines in research and diagnostic laboratories,” they wrote. Aguzzi says he was “totally shocked” by the finding and introduced safety measures to prevent aerosol spread at his own lab, but the paper drew little attention elsewhere.

The moratorium will "obviously" cause delays in research, but given the very long incubation periods in prion diseases, the impact of a 3-month hiatus will be limited, Comoy says. His research team at CEA also works on other neurodegenerative diseases, including Alzheimer's disease and Parkinson's disease, and will shift some of its efforts to those.

Although Jaumain’s diagnosis upset many in the field, it hasn't led to an exodus among researchers in France, Haïk says: “I know of only one person who resigned because they were so worried.”

With reporting by Martin Enserink.

Posted in: EuropeHealthScientific Community

doi:10.1126/science.abl6587

https://www.sciencemag.org/news/2021/07/france-issues-moratorium-prion-research-after-fatal-brain-disease-strikes-two-lab

Variant Creutzfeldt–Jakob Disease Diagnosed 7.5 Years after Occupational Exposure

Variant Creutzfeldt–Jakob disease was identified in a technician who had cut her thumb while handling brain sections of mice infected with adapted BSE 7.5 years earlier. The long incubation period was similar to that of the transfusion-transmitted form of the disease.

Variant Creutzfeldt–Jakob Disease Diagnosed 7.5 Years after Occupational Exposure

TO THE EDITOR:

We report a case of variant Creutzfeldt–Jakob disease (CJD) that was plausibly related to accidental occupational exposure in a technician who had handled murine samples contaminated with the agent that causes bovine spongiform encephalopathy (BSE) 7.5 years earlier.

In May 2010, when the patient was 24 years of age, she worked in a prion research laboratory, where she handled frozen sections of brain of transgenic mice that overexpressed the human prion protein with methionine at codon 129. The mice had been infected with a sheep-adapted form of BSE. During this process, she stabbed her thumb through a double pair of latex gloves with the sharp ends of a curved forceps used to handle the samples. Bleeding was noted at the puncture site.

In November 2017, she began having burning pain in the right shoulder and neck. The pain worsened and spread to the right half of her body during the following 6 months. In November 2018, an examination of a sample of cerebrospinal fluid (CSF) obtained from the patient was normal. Magnetic resonance imaging (MRI) of the brain showed a slight increase in the fluid-attenuated inversion recovery (FLAIR) signal in the caudates and thalami (Fig. S1A and S1B in the Supplementary Appendix, available with the full text of this letter at NEJM.org). In January 2019, she became depressed and anxious and had memory impairment and visual hallucinations. There was hypertonia on the right side of her body. At that time, an analysis of CSF for 14-3-3 protein was negative. In March 2019, MRI showed an increased FLAIR signal in pulvinar and dorsomedial nuclei of thalami (Fig. S1C through S1E).

Figure 1.

Detection of Abnormal Prion Protein in Biologic Fluid Samples and Postmortem Findings.

The patient was found to be homozygous for methionine at codon 129 of the prion protein gene without mutation. An analysis of a sample of CSF on real-time quaking-induced conversion analysis was negative for a diagnosis of sporadic CJD. However, an analysis of plasma and CSF by means of protein misfolding cyclic amplification was positive for the diagnosis of variant CJD (Figure 1A and 1B). The patient died 19 months after the onset of symptoms. Neuropathological examination confirmed the diagnosis of variant CJD (Figure 1C and 1D). Western blot analysis showed the presence of type 2B protease-resistant prion protein in all sampled brain areas. The clinical characteristics of the patient and the postmortem neuropathological features were similar to those observed in 27 patients with variant CJD who had previously been reported in France.1 (Additional details are provided in the Supplementary Appendix.)

There are two potential explanations for this patient’s condition. Oral transmission from contaminated cattle products cannot be ruled out because the patient was born at the beginning of the French BSE outbreak in cattle. However, the last two patients who had confirmed variant CJD with methionine homozygosity at codon 129 in France and the United Kingdom died in 2014 and 2013, respectively, which makes oral transmission unlikely. In France, the risk of variant CJD in 2019 was negligible or nonexistent in the post-1969 birth cohort.2

Percutaneous exposure to prion-contaminated material is plausible in this patient, since the prion strain that she had handled was consistent with the development of variant CJD.3 The 7.5-year delay between the laboratory accident and her clinical symptoms is congruent with the incubation period in the transfusion-transmitted form of the disease. The ability of this strain to propagate through the peripheral route has been documented, and experimental studies with scrapie strains have shown that scarification and subcutaneous inoculation are effective routes.4,5 The last known Italian patient with variant CJD, who died in 2016, had had occupational contact with BSE-infected brain tissues, although subsequent investigation did not disclose a laboratory accident (Pocchiari M, Italian Registry of CJD: personal communication). Thus, the last two cases of variant CJD outside the United Kingdom have been associated with potential occupational exposure. Such cases highlight the need for improvements in the prevention of transmission of variant CJD and other prions that can affect humans in the laboratory and neurosurgery settings, as outlined in the Supplementary Appendix.

Jean-Philippe Brandel, M.D. Assistance Publique–Hôpitaux de Paris, Paris, France

M. Bustuchina Vlaicu, M.D. Groupe Hospitalier Nord-Essonne, Orsay, France

Audrey Culeux, B.Sc. INSERM Unité 1127, Paris, France

Maxime Belondrade, M.Sc. Daisy Bougard, Ph.D. Etablissement Français du Sang, Montpellier, France

Katarina Grznarova, Ph.D. Angeline Denouel, M.Sc. INSERM Unité 1127, Paris, France

Isabelle Plu, M.D. Elodie Bouaziz-Amar, Pharm.D., Ph.D. Danielle Seilhean, M.D., Ph.D. Assistance Publique–Hôpitaux de Paris, Paris, France

Michèle Levasseur, M.D. Groupe Hospitalier Nord-Essonne, Orsay, France

Stéphane Haïk, M.D., Ph.D. INSERM Unité 1127, Paris, France stephane.haik@upmc.fr

Supported by a grant (ANR-10-IAIHU-06) from Programme d’Investissements d’Avenir and Santé Publique France.

Disclosure forms provided by the authors are available with the full text of this letter at NEJM.org.

5 References

July 2, 2020

N Engl J Med 2020; 383:83-85

DOI: 10.1056/NEJMc2000687

Metrics

https://www.nejm.org/doi/full/10.1056/NEJMc2000687

JAMA. 2001;285(6):733-734. doi:10-1001/pubs.JAMA-ISSN-0098-7484-285-6-jlt0214

February 14, 2001

Diagnosis and Reporting of Creutzfeldt-Jakob Disease

Terry S. Singeltary, Sr

Author Affiliations

JAMA. 2001;285(6):733-734. doi:10-1001/pubs.JAMA-ISSN-0098-7484-285-6-jlt0214

To the Editor: In their Research Letter, Dr Gibbons and colleagues1 reported that the annual US death rate due to Creutzfeldt-Jakob disease (CJD) has been stable since 1985. These estimates, however, are based only on reported cases, and do not include misdiagnosed or preclinical cases. It seems to me that misdiagnosis alone would drastically change these figures. An unknown number of persons with a diagnosis of Alzheimer disease in fact may have CJD, although only a small number of these patients receive the postmortem examination necessary to make this diagnosis. Furthermore, only a few states have made CJD reportable. Human and animal transmissible spongiform encephalopathies should be reportable nationwide and internationally.

https://jamanetwork.com/journals/jama/article-abstract/1031186

WEDNESDAY, OCTOBER 15, 2025

US NATIONAL PRION DISEASE PATHOLOGY SURVEILLANCE CENTER CJD TSE REPORT 2025

https://prionunitusaupdate.blogspot.com/2025/10/us-national-prion-disease-pathology.html

FRIDAY, NOVEMBER 21, 2025

While no one was watching: Tenuous status of CDC prion unit, risk of CWD to people worry scientists

https://chronic-wasting-disease.blogspot.com/2025/11/while-no-one-was-watching-tenuous.html

SATURDAY, JANUARY 10, 2026

Neuropsychiatric symptoms in sporadic Creutzfeldt-Jakob disease, a review

https://creutzfeldt-jakob-disease.blogspot.com/2026/01/neuropsychiatric-symptoms-in-sporadic.html

https://prpsc.proboards.com/thread/191/neuropsychiatric-symptoms-sporadic-cjd-review

Terry S. Singeltary Sr.