Friday, February 18, 2022

Michigan Chronic Wasting Disease CWD TSE Prion Update February 2022

Michigan Chronic Wasting Disease CWD TSE Prion Update February 2022

CWD in Michigan

Since May 2015 when the first CWD deer was found in Michigan, CWD has been confirmed in a number of townships in the Lower Peninsula. As of October 2018, a CWD positive deer was found in the Upper Peninsula in Dickinson County. CWD was also found in August 2008 at a Kent County deer farm facility and in January 2017 in two captive deer that were from a deer farm facility in Mecosta County.



CWD TESTING RESULTS


Desperado Deer: The Persistent Problem of Captive Deer Running Wild

by Editor | May 8, 2018 | Conservation, Hunting

Cervid Escapees – Measuring the Problem

For starters, no one knows for sure how many deer escape from high-fence facilities each year. Neither the DNR nor the Michigan Department of Agriculture and Rural Development keep accurate, complete records of the number of escapees reported by citizens and/or investigated by DNR conservation officers. Only in 2017 did the DNR first begin using an electronic database to monitor escaped cervids.

Currently, there are 333 licensed captive cervid facilities in the state, most of which are breeding farms (161) or hunting ranches (132), holding over 21,000 whitetail deer, fallow deer, red deer, Sitka deer and elk. While the number of deer escapees voluntarily reported has declined over recent years, the numbers do not include escapees that are never reported.


Chronic wasting disease (CWD) is a transmissible neurological disease found in deer and elk populations that produces small lesions in brains of infected animals. As a result, CWD causes weight loss and a decline in body control. It is a species-specific disease, and there have been no cases in humans or other animals.

Currently, to determine the presence of CWD, brain and lymph node samples are taken by an accredited veterinarian after an animal dies. These samples are then submitted for testing.

As part of their operations, all privately-owned cervid (POC) facilities in Michigan are required to submit samples. The number of samples that must be submitted depends on what specific program that a producer participates in: the Chronic Wasting Disease Herd Certification Program (CWD HCP) or the Surveillance Program.

First, for the CWD HCP, all cervids 12 months of age and older that die for any reason must be tested for CWD.

Second, all facilities that are not a part of the CWD HCP must participate in the Surveillance Program. The Surveillance Program requires that all animals 12 months of age and older that die from illness, injury, or euthanasia due to disease must be tested for CWD. In addition, 25% of cervids slaughtered, hunted, or culled must be tested. This number is calculated on an annual basis. In general, all facilities that have at least one death must test at least this one animal. 

Samples for either of these programs can be submitted to a private veterinarian, the Michigan State University Veterinary Diagnostic Lab, or an MDARD drop off location. 

For more information, contact the MDARD Cervid Program.

General Questions/Concerns: MDARD-Cervid@Michigan.gov

Cervid Program Manager: 

Dr. Jennifer Calogero CalogeroJ@Michigan.gov 517-284-5692

Cervid Program Secretary: Melanie Hart HartM1@Michigan.gov 517-284-5679


Privately Owned Cervidae

Raising deer and elk in captivity is jointly regulated by the DNR and the Michigan Department of Agriculture and Rural Development. The DNR oversees the registration of facilities containing farmed cervids and performs inspections of these operations. MDARD manages the disease programs for the state’s POC facilities. Participation in disease surveillance programs - such as those for chronic wasting disease (CWD) and the bovine tuberculosis (TB) - ensures for a robust industry by increasing the marketability of these animals by decreasing their potential for carrying disease. There are nearly 300 licensed facilities in 76 Michigan counties totaling over 63,000 fenced acres. The division conducts about 95 facility inspections per year to ensure that fencing and recordkeeping meet industry standards.

2021 Wildlife Health Section Accomplishments

Tested over 8,000 deer heads for bovine tuberculosis and 

2,500 heads for chronic wasting disease. 

While CWD is not known to be zoonotic, bTB can infect humans, domestic animals and wild animals beyond white-tailed deer.


***> Tested ...and 2,500 heads for chronic wasting disease. 

MDNR estimates put the Michigan deer population around 1.75 million for 2019. Dec 25, 2019

Issues Pros and Cons Despite federal, state, and local regulations and other measures intended to prevent the spread or reduce CWD prevalence, the disease continues to be identified in captive cervid facilities certified as “low risk” through the United States Department of Agriculture (USDA) Herd Certification Program and the CFIA (Canadian Food Inspection Agency) Voluntary Herd Certification Programs (participating in a federally-approved CWD program was a measure of the ATA program). According to the USDA data reports, there were 22 new CWD-positive captive cervid facilities identified in FY2020; 41 percent of those were either enrolled or certified in the federal HCP program. There are a variety of unregulated processes used to collect urine, and they often result in the accumulation of a mixture of secretions, therefore providing concurrent contaminated risks. In addition, urine products are frequently batched/combined from multiple locations and distributed across the country, which increases the likelihood of CWDinfected urine entering the market. There are currently no standard regulations to ensure that urine collected for lures and attractants are disease-free. 

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Biological

Nationally, CWD continues to be found in captive cervid facilities. 

From the years 2012 to 2021, there have been 66 privately owned cervid facilities nationally where CWD has been identified. 

Of those 66 facilities, 39 were enrolled in the HCP, and 32 of those facilities were HCP-certified (meaning there had been at least five years of disease monitoring and no rule violations) indicating low risk for CWD. 

This national USDA CWD HCP is not mandatory, and more importantly, recent CWD events show that it does not and cannot guarantee that captive deer herds are CWD free. 

To date, CWD has been found in more than 140 captive deer herds in 16 states and two Canadian provinces. 



Front. Vet. Sci., 18 January 2022 | https://doi.org/10.3389/fvets.2021.824815

Evaluation of Real-Time Quaking-Induced Conversion, ELISA, and Immunohistochemistry for Chronic Wasting Disease Diagnosis

All, except one, CWD positive RLNs analyzed were from ten Counties geographically located in the West Michigan region of the Lower Peninsula. Taken together, we show evidence that the RT-QuIC assay is comparable to ELISA and IHC and could be helpful for routine CWD detection in surveillance programs. RT-QuIC also demonstrated that CWD prions are distributed across lymph nodes in a variety of anatomic locations.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8803730/pdf/fvets-08-824815.pdf

MICHIGAN CWD CAPTIVE

11/4/2021 2, 3 Y Male MI Kent Elk Breeder Yes Yes 0 Depopulated

7/15/2021 4 Y Female MI Montcalm WTD Breeder No No 109 Quarantine

4/18/2021 2.5 Y Male MI WTD Shooter No No ukn Quarantine

3/3/2021 4 Y Male MI Montcalm WTD Shooter No NA 14 Quarantine

12/2019 3, 4.5 Y Males MI Newaygo WTD Shooter No No >600 Quarantine

4/2019 2.5 Y Female MI Montcalm WTD Breeder No NA 113 Depopulated

12/2017 1.5 Y Female MI Mecosta WTD Breeder Yes Yes 525 Quarantined

1/2017 2Y Female MI Mecosta WTD & Sika deer Shooter No NA 71 Depopulated


Michigan:

September, 2019: NVSL confirmed CWD in a two year old female white-tailed deer in Montcalm County. The doe was a natural addition to the breeding herd which consists of 50 white-tailed deer. This herd is not enrolled in the Federal HCP, is within a CWDendemic area, and is under quarantine. 


Michigan: One new CWD positive herd

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


Farmed Cervid Chronic Wasting Disease Management and Response Activities 2021 Cooperative Agreements



APHIS also conducts monitoring and surveillance activities to detect diseases that affect cervids, including chronic wasting disease (CWD) and tuberculosis (TB). APHIS’ voluntary national CWD Herd Certification Plan (HCP) works with States, Tribes, and the cervid industry to control CWD in farmed cervids by allowing the interstate movement only from certified herds. 

Currently, 28 States participate in the national CWD HCP. In FY 2019 APHIS tested more than 11,000 farmed cervids for CWD. 

As a result, APHIS identified 17 new CWD positive farmed cervid herds.

https://www.usda.gov/sites/default/files/documents/20aphis2021notes.pdf 

Wild Cervid Chronic Wasting Disease Management and Response Activities 2021 Funding Opportunity

Tribal Nations Wild Cervid Chronic Wasting Disease Opportunities 2021 Funding Opportunity


VS Farmed Cervid Chronic Wasting Disease Management and Response Activities 2021 Funding Opportunity 

RISK, UNCERTAINTY AND DECISION-MAKING: ASSESSING CHRONIC WASTING DISEASE OCCURRENCE RISK ACROSS AN EMERGENCE SPECTRUM

Exposure hazards included point locations of captive cervid facilities, deer processors and taxidermists, and out-of-area hunting connectivity. 

As of 2018, there were a total of 296 ranch and full-registration facilities in Michigan. In terms of their spatial distribution, there were facilities in 196 out of 1240 townships, and 71 out of 83 counties (Fig. 2.1). There were 468 registered deer processors and taxidermists in 2017, the year for which data were available. Processors and taxidermists occurred in 696 out of 1240 townships, and 82 out of 83 counties (Fig. 2.2). Lastly, out-of-area hunting was based on both intrastate and interstate metrics. For intrastate hunting, the percentage of respondents that travelled from one county to another was scaled up to the total number of hunters that reside in a county. CWD positive counties included Clinton, Dickinson, Eaton, Gratiot, Ingham, Ionia, Jackson, Kent and Montcalm counties. The average number of hunters per resident county from 2013 – 2017 who travelled to a CWD positive county ranged from 0 – 3832 per year (Fig. 2.3). A low number (i.e., low connectivity) of interstate hunters ranged from 0 – 1059 for the 5-year average, whereas a high number ranged from 1060 – 3832 (Fig. 2.3). Interstate hunting was quantified as the number of Michigan resident hunters who purchased an out-of-state license in Wisconsin between years 2013 – 2017 (i.e., nonresident license). For interstate connectivity, I found that average annual number of Michigan county residents that traveled to Wisconsin between 2013 –2017 was 0 – 170 per year (Fig. 2.4). A low number (i.e., low connectivity) of interstate hunters ranged from 0 – 39 for the 5-year average, whereas a high number ranged from 40 – 170 (Fig. 2.4). 

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In 2017, the Michigan Department of Natural Resources (MDNR) detected CWD in a 3- year-old white-tailed doe submitted during an early season youth hunt (MDNR 2017). Additional surveillance in the area during 2017 identified 45 total CWD-positive animals in a concentrated disease focus in the west-central Lower Peninsula of Michigan within Kent and Montcalm counties. Nine previous CWD detections had occurred in the state in 2015 and 2016; however, the 2017 detections were the first evidence that CWD might be widespread and established within Michigan. Based on a single year of observation, predicting the area affected by the cluster of disease with distance benchmarks would likely fail to fully encapsulate the affected area. Furthermore, based on the sparsity of data, fitting complex disease models was not possible. Thus, there was an immediate need for an alternative approach that could more appropriately estimate the extent of CWD and identify locations at high risk using limited available information 

https://d.lib.msu.edu/etd/49428/datastream/OBJ/View/

Prion protein polymorphisms in Michigan white-tailed deer (Odocoileus virginianus)

Caitlin N. Ott-ConnORCID Icon,Julie A. Blanchong &Wes A. Larson

Pages 183-190 | Received 22 Jul 2021, Accepted 01 Oct 2021, Published online: 09 Nov 2021

Download citation https://doi.org/10.1080/19336896.2021.1990628 ;

ABSTRACT

Chronic Wasting Disease (CWD), a well-described transmissible spongiform encephalopathy of the Cervidae family, is associated with the aggregation of an abnormal isoform (PrPCWD) of the naturally occurring host prion protein (PrPC). Variations in the PrP gene (PRNP) have been associated with CWD rate of infection and disease progression. We analysed 568 free-ranging white-tailed deer (Odocoileus virginianus) from 9 CWD-positive Michigan counties for PRNP polymorphisms. Sampling included 185 CWD-positive, 332 CWD non-detected, and an additional 51 CWD non-detected paired to CWD-positives by sex, age, and harvest location. We found 12 polymorphic sites of which 5 were non-synonymous and resulted in a change in amino acid composition. Thirteen haplotypes were predicted, of which 11 have previously been described. Using logistic regression, consistent with other studies, we found haplotypes C (OR = 0.488, 95% CI = 0.321–0.730, P < 0.001) and F (OR = 0.122, 95% CI = 0.007–0.612, P < 0.05) and diplotype BC (OR = 0.340, 95% CI = 0.154–0.709, P < 0.01) were less likely to be found in deer infected with CWD. As has also been documented in other studies, the presence of a serine at amino acid 96 was less likely to be found in deer infected with CWD (P < 0.001, OR = 0.360 and 95% CI = 0.227–0.556). Identification of PRNP polymorphisms associated with reduced vulnerability to CWD in Michigan deer and their spatial distribution can help managers design surveillance programmes and identify and prioritize areas for CWD management.

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Results

PRNP sequences were determined for 568 free-ranging white-tailed deer from 9 CWD-positive Michigan counties. Of these samples, 185 were CWD-positive, 332 were CWD non-detected, and an additional 51 CWD non-detected were paired to CWD-positives to control for sex, age, and harvest location (Figure 1). Within the analysed 625bp region of the PRNP gene, we detected 12 single nucleotide polymorphisms (SNPs), 9 of which had been previously reported [22, 29, 33, 36, 38–41]. Of the 12 SNPs, 5 were non-synonymous, resulting in a change to the amino acid sequence (Table 1). BLAST and literature searches indicated that 589A/G, 642 G/A, and 643 C/A had not previously been reported. Full associated sequences have been deposited in GenBank under accession numbers MZ913400 – MZ913401.

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As CWD detections continue to increase the areas under surveillance, the use of regionally specific data to allocate testing efforts and funding will be pivotal for success. Identification of PRNP polymorphisms associated with reduced vulnerability to CWD and their spatial distribution and prevalence may help managers design surveillance programmes to identify and prioritize areas for CWD management when partnered with movement data and anticipated deposition of prions onto the landscape over time.


77. Assessing chronic wasting disease strain differences in free-ranging cervids across the United States

Kaitlyn M. Wagnera, Caitlin Ott-Connb, Kelly Strakab, Bob Dittmarc, Jasmine Battend, Robyn Piercea, Mercedes Hennessya, Elizabeth Gordona, Brett Israela, Jenn Ballarde and Mark D Zabela

aPrion Research Center at Colorado State University; bMichigan Department of Natural Resources; cTexas Parks and Wildlife Department; dMissouri Department of Conservation, 5. Arkansas Game and Fish Commission CONTACT Kaitlyn M. Wagner miedkait@rams.colostate.edu

ABSTRACT

Background/Introduction: Chronic wasting disease (CWD) is an invariably fatal prion disease affecting captive and free-ranging cervids, including white-tailed deer, mule deer, moose, elk, and reindeer. Since the initial description of the disease in the 1960’s, CWD has spread to 23 states, 3 Canadian Provinces, South Korea, Norway and, most recently, Finland. While some outbreaks of CWD were caused by transport of infected animals from endemic regions, the origin of CWD in other epizootics is unclear and has not been characterized. Previous studies have shown that there are two distinct strains of CWD. However, the continuous spread and the unclear origin of several outbreaks warrant continued surveillance and further characterization of strain diversity.

Materials and Methods: To address these knowledge gaps, we used biochemical tests to assess strain differences between CWD outbreaks in Michigan, Texas, Missouri, and Colorado, USA. Brain or lymph node samples were homogenized and digested in 50 µg/mL proteinase K (PK). These samples were then run on a Western blot to assess glycoform ratio and electrophoretic mobility. Texas samples were digested in 100 µg/mL PK. To assess conformational stability, brain or lymph node homogenates were incubated in increasing concentrations of guanidine hydrochloride from 0 M to 4 M in 0.5 M increments. Samples were then precipitated in methanol overnight, washed and PK digested in 50 µg/mL PK before slot blotting.

Results: Our results have found significant differences in glycoform ratio between CWD from Michigan and Colorado, but no differences were observed in conformational stability assays. Interestingly, when testing our CWD isolates from Texas to analyse electrophoretic mobility and glycoform ratio, we found that these samples did not exhibit the characteristic band shift when treated with PK, but PK resistant material remained. Additionally, results from our conformational stability assay demonstrate a unique profile of these Texas isolates. Testing of samples from Missouri is currently underway.

Conclusions: Thus far, our data indicate that there are strain differences between CWD circulating in Michigan and CWD in Colorado and provide important insight into CWD strain differences between two non-contiguous outbreaks. We have also identified a unique strain of CWD in Texas with biochemical strain properties not seen in any of our other CWD isolates. These results highlight the importance of continued surveillance to better understand this devastating disease. These results have important implications for CWD emergence, evolution and our understanding of prion strain heterogeneity on the landscape.


Special Surveillance Area (SSA) Counties for Farmed Deer

Calhoun (CA)

Clinton (CN)

Dickinson (DK)

Eaton (ET)

Gratiot (GT)

Hillsdale (HD)

Ingham (IN)

Ionia (IO)

Jackson (JK)

Kent (KN)

Lenawee (LN)

Livingston (LV)

Mecosta (MT)

Menominee (MO)

Montcalm (MT)

Newaygo (NW)

Saginaw (SG)

Shiawassee (SH)

Washtenaw (WA)

SSAs as of December 18, 2019

SSAs are established when a free-ranging or farmed deer is identified with chronic wasting disease.

Contact the Michigan Department of Agriculture and Rural Development’s Cervid Program at MDARD-Cervid@Michigan.gov or 517-284-5679.


Expanding Distribution of Chronic Wasting Disease ACTIVE

By National Wildlife Health Center February 5, 2022

https://www.usgs.gov/centers/nwhc/science/expanding-distribution-chronic-wasting-disease

Michigan CWD Testing Results Deer Harvested in 2021 Statewide Total 22 Positive To Date For Year in Wild

CWD Testing Results for Deer Harvested in 2021

Test results updated as of December 13, 2021.

Totals reflected in this update only include those with final test results.

Deer with pending results are not included in these totals.

Zone Total Tested Number Positive

UP CWD Core Surveillance Area 193 0

South Isabella + Gratiot 749 3

South Jackson 855 12

Totals 1797 15

Testing numbers above are part of the county totals in the larger table below. 

County Name Total Tested Number Positive

Allegan 290 0

Barry 150 0

Berrien 77 0

Branch 104 0

Calhoun 139 0

Cass 64 0

Eaton 82 0

Hillsdale 204 0

N. Jackson 135 0

Kalamazoo 196 0

Lenawee 118 0

Livingston 68 0

Macomb 13 0

Monroe 34 0

Oakland 43 0

St. Joseph 81 0

Van Buren 155 0

Washtenaw 178 0

Wayne 9 0

Total to date 2106 0

These counties are open for hunter service testing November 15-18 ONLY. There are no surveillance goals.

County Name Total Tested Number Positive

Clinton 45 0

Dickinson (non-core) 3 0

Ingham 32 0

Ionia 35 1

Kent 47 1

Montcalm 53 5

Total to date 215 7 Deer tested in remainder of state 113 0 Positive

Statewide Total 3865 22 Positive 


Michigan MDARD Chronic Wasting Disease Confirmed in Two Farmed Elk from Kent County 

For immediate release: November 18, 2021 Media contact: Chelsea Lewis-Parisio, 517-331-1151

MDARD: Chronic Wasting Disease Confirmed in Two Farmed Elk from Kent County 

LANSING, MI – Today, the Michigan Department of Agriculture and Rural Development (MDARD) confirmed two cases of chronic wasting disease (CWD) in elk from a farmed cervid facility in Kent County. The two infected elk, a two-and-a-half-year-old and a three-and-a-half-year-old, were discovered through disease tracing efforts that resulted from finding CWD in a different Michigan farmed cervid herd. These are the first cases of CWD in Michigan elk.

CWD is a fatal neurological disease that affects different cervid species, including white-tailed deer, mule deer, elk, and moose. The disease can be transmitted directly from one animal to another and indirectly through the environment. While an infected animal may appear healthy for months or years, it will eventually display abnormal behavior, progressive weight loss, and physical debilitation in the latter stages of the disease.

“The discovery of chronic wasting disease in elk housed at a facility linked to a positive animal is not surprising,” said State Veterinarian Dr. Nora Wineland, DVM. “MDARD’s main priority is to limit the spread of this disease by working together with other state departments, farmers, and ranchers. These findings underscore how important it is to pay attention to CWD and the movement of animals that may allow the disease to spread.”

The presence of CWD in farmed cervid facilities and free-ranging deer is not new to Michigan. Since 2008, including these new cases, CWD has been detected at nine Michigan cervid farms in the following counties: Kent (2), Mecosta (3), Montcalm (3), and Newaygo.

No wild elk have tested positive for CWD in Michigan. The disease was first discovered in free-ranging deer in May 2015; cases have been found across nine counties in Michigan’s Upper and Lower Peninsulas. To date, 37 free-ranging white-tailed deer have tested positive for CWD in Kent County. 

As part of MDARD’s disease response, investigations are ongoing to rule out any possible exposure to other farmed cervids.

Currently, there have been no reported cases of CWD infection in humans. However, as a precaution, the U.S. Centers for Disease Control and the World Health Organization recommend that animals that have tested positive for CWD should not be consumed as food by either humans or domestic animals.

More information about CWD can be found at http://Michigan.gov/CWD or http://Michigan.gov/MDARD-Cervid.

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WEDNESDAY, NOVEMBER 10, 2021 

Prion protein polymorphisms in Michigan white-tailed deer (Odocoileus virginianus)


WEDNESDAY, OCTOBER 27, 2021 

Michigan shifts approach to monitor spread of deadly deer disease deer CWD TSE Prion 220 cases confirmed in WILD to date, captive? 


FRIDAY, OCTOBER 22, 2021

Michigan CWD TSE Prion TOTAL WILD CERVID 220 POSITIVE TO DATE, CAPTIVE CWD TOTAL


Michigan CWD TSE Prion TOTAL WILD CERVID 220 POSITIVE TO DATE, CAPTIVE CWD TOTAL???

PERSONAL COMMUNICATION DNR...see;

Mon, Aug 9, 2021 11:46 am

''The interactive hot map you are referencing is updated regularly, at least once a month, but even more regularly during hunting season as that is when we receive most samples and theoretical positives. All 209 animals to date are wild. No captive cervid deer are listed in our testing metrics because they fall into a different category of management as overseen by Michigan Department of Agriculture and Rural Development (MDARD). Because they are captive they are treated as domestic animals – same as cows, horses, and pigs. If you were inquiring about CWD+ private cervids you will have to reach out to them as we don’t so much focus on total individuals positive as we do positive herds and locations (which again they would be best to ask).''
 
''Our 2021 testing totals account for 11 positives this year, all USDA-APHIS or Disease Permit culled animals in Gratiot (3) and Jackson (8) counties.  I am digging into when the interactive map was last updated now, but at a worst that would but our total positive at 220 over Michigan’s history of testing if it hadn’t been recently updated (which is possible as USDA-APHIS shooting just recently started up again in July after a multi-month break).''

YOU can see CWD here;


Where has chronic wasting disease (CWD) been found in Michigan?

Since the initial finding of CWD on May 20, 2015, free-ranging deer in Clinton, Dickinson, Eaton, Gratiot, Ingham, Ionia, Jackson, Kent and Montcalm counties have been positively confirmed with CWD. Please visit Michigan.gov/CWD for more information on CWD and the latest news and testing updates. See pages 56-57 and 61-62 for important regulations pertaining to CWD. 


Assessing drivers of spread and transmission of Chronic Wasting Disease in Michigan deer

Primary Contact: Dr. Dwayne Etter, DNR Wildlife Division, Lansing, Michigan


Phone: (517) 284-4720

DNR Financial Support: $120,149 in FY19, $502,737 total.

Study Area: South-central Lower Peninsula

Time Frame: 10/1/2017-9/30/2022

Abstract:

The occurrence of chronic wasting disease (CWD) in Michigan challenges the foundations of wildlife conservation, both in the short term and perhaps more significantly in the longer term. In the short term, CWD is causing reallocation of precious financial and staff-time resources and will be widely disruptive to existing programs of the Michigan Department of Natural Resources (DNR). In the longer term, diseases such as CWD pose a threat to the financial cornerstone of fisheries and wildlife programs because sales of deer hunting licenses represent a large proportion of annual revenue for the Division of Wildlife. Recognizing these threats, the Division of Wildlife included wildlife disease in its Guiding Principles and Strategies (Objective 1.3: monitor and preserve the health of Michigan’s wildlife) and prepared a comprehensive Surveillance and Response Plan for Chronic Wasting Disease of Free-ranging and Privately Owned Cervids.

Chronic wasting disease is a transmissible spongiform encephalopathy that infects North American cervids including white-tailed deer (Williams 2005). The infectious agent of CWD is a misfolded protein, a prion, which accumulates in the brainstem and lymphatic tissue of infected animals and results in neurodegeneration and eventual death. In states where CWD is established it has emerged as a major threat, reducing the health of populations and causing long-term population decline (Edmunds et al. 2016, Gross and Miller 2001, Manjerovic et al. 2014).

The discovery of CWD in Michigan creates an immediate need for population monitoring and surveillance of at-risk deer populations. Since 2015, nine infected individuals have been identified following collection through state surveillance efforts, representing key successes in targeted disease management. However, the continued discovery of infected individuals in 2016 suggests a high likelihood that additional infected individuals remain on the landscape. The occurrence of a small number of infected animals across a relatively small geographic region in mid-Michigan indicates that the disease is still emerging.

What distinguishes the research proposed here from extensive work done in other states is that CWD is still in an emergent phase in Michigan. Michigan discovered the disease early during a time when transmission of the disease may be more dependent on the density of deer on the landscape because most infections are through direct contact of infected animals with susceptible individuals. This situation is similar only to New York and Minnesota. In all other states where CWD has been discovered, the disease was already well established, and transmission included infection mediated by contact of susceptible individuals with severely contaminated environments. Our research in Michigan is intended to explore management options for the control of an emerging occurrence of CWD through better understanding of behavior and population dynamics of deer inhabiting areas of known infection. 

The goal of this research is to improve the cost-efficiency of detecting CWD when it is still rare and removing animals from the landscape to control the spread of disease, by reducing contact among deer and potentially eliminating infectious animals. We intend to take a multi-pronged approach to accomplish this goal and the work described here will complement another study that seeks to develop new methods for detecting and removing diseased animals. The effort described here is designed to accumulate a dataset on movement behavior of deer that is of high temporal and spatial resolution to address questions about dispersal rates, directions and distances; evaluate hypotheses about environmental factors that are likely influences on dispersal behavior; parameterize risk maps of first-order contact for Michigan in concert with data and prior research in New York State; and create models of the interaction of landscape contexts (e.g., suburban, rural) and habitat characteristics that can be used to direct hunters and biologists to increase the efficiency of surveillance and removal actions. Our objectives address the strategic plans set forth by the Michigan DNR to “1.3.1: Develop and implement strategies to prevent and control diseases before they occur; 1.3.2: Respond to wildlife disease outbreaks; 1.3.4: Conduct research and monitoring to provide information to make management recommendations regarding wildlife disease; 1.3.5: Raise awareness regarding current and emerging wildlife health issues; and 1.3.6: Work with State and Federal agencies, and stakeholders to address wildlife health issues.” 

12 IC4117 (Rev. 02/02/2021) 

control of an emerging occurrence of CWD through better understanding of behavior and population dynamics of deer inhabiting areas of known infection.

The goal of this research is to improve the cost-efficiency of detecting CWD when it is still rare and removing animals from the landscape to control the spread of disease, by reducing contact among deer and potentially eliminating infectious animals. We intend to take a multi-pronged approach to accomplish this goal and the work described here will complement another study that seeks to develop new methods for detecting and removing diseased animals. The effort described here is designed to accumulate a dataset on movement behavior of deer that is of high temporal and spatial resolution to address questions about dispersal rates, directions and distances; evaluate hypotheses about environmental factors that are likely influences on dispersal behavior; parameterize risk maps of first-order contact for Michigan in concert with data and prior research in New York State; and create models of the interaction of landscape contexts (e.g., suburban, rural) and habitat characteristics that can be used to direct hunters and biologists to increase the efficiency of surveillance and removal actions.

Our objectives address the strategic plans set forth by the Michigan DNR to “1.3.1: Develop and implement strategies to prevent and control diseases before they occur; 1.3.2: Respond to wildlife disease outbreaks; 1.3.4: Conduct research and monitoring to provide information to make management recommendations regarding wildlife disease; 1.3.5: Raise awareness regarding current and emerging wildlife health issues; and 1.3.6: Work with State and Federal agencies, and stakeholders to address wildlife health issues.” 

Management of Chronic Wasting Disease in Michigan

Primary Contact: Dr. Kelly Straka, DNR Wildlife Division, Lansing, Michigan


Phone: (517) 336-5030

DNR Financial Support: $50,000 in FY19, $250,000 total.

Study Area: Statewide.

Time Frame: 10/01/2016-09/30/2022

Abstract: Chronic Wasting Disease (CWD) is a transmissible spongiform encephalopathy that infects North American cervids including white-tailed deer (Williams 2005). The infectious agent of CWD is a misfolded protein, a prion, that accumulates in the brainstem and lymphatic tissue of infected animals and results in neurodegeneration and eventual death. In states where CWD is established, it has emerged as a major threat, reducing the health of populations and causing long-term population decline (Edmunds et. al. 2016, Gross and Miller 2001, Manjerovic et. al. 2014). 15 IC4117 (Rev. 02/02/2021) 

The occurrence of CWD in Michigan challenges the foundations of wildlife conservation, both in the short term and perhaps more significantly in the longer term. In the short term, CWD is causing reallocation of precious financial and staff-time resources and will be widely disruptive to existing programs. In the longer term, diseases such as CWD pose a threat to the financial cornerstone of fisheries and wildlife programs because sales of deer hunting licenses represent such a large proportion of annual revenue. Recognizing these threats, the Wildlife Division included wildlife disease in its Guiding Principles and Strategies (Objective 1.3: Monitor and preserve the health of Michigan’s wildlife) and prepared a comprehensive Surveillance and Response Plan for Chronic Wasting Disease of Free-ranging and Privately Owned Cervids.

The discovery of CWD in Michigan creates an immediate need for tools that better assess the return-oninvestment of funds for surveillance and management of CWD. We propose building on risk assessment and modeling that was previously developed during a CWD outbreak in New York. There, we showed how costs of CWD containment could be reduced dramatically by using risk modeling procedures and mapping areas where management action would have the greatest impact on disease control (Williams et. al. 2014). We plan to expand on those efforts by adapting them to Michigan and drawing on newly emerging tools for population estimation and risk analysis procedures that we have been using on other research (e.g., local-scale monitoring of deer populations using distance sampling and evaluation of wild turkey harvest regulations using statistical risk modeling).

Our objectives address the strategies set forth in the Wildlife Division’s Guiding Principles and Strategies to “1.3.1: Develop and implement strategies to prevent and control diseases before they occur, 1.3.2: Respond to wildlife disease outbreaks, 1.3.4: Conduct research and monitoring to provide information to make management recommendations regarding wildlife disease, 1.3.5: Raise awareness regarding current and emerging wildlife health issues and 1.3.6: Work with State and Federal agencies and stakeholders to address wildlife health issues.” Specifically, we will provide managers with decision tools to: (1) evaluate the risk of spread of disease against the geographic extent of management action and attendant financial and political costs, (2) evaluate management alternatives to control CWD and assess the risk of local cases of CWD transitioning from emergent status to established status (where the disease becomes a self-sustaining reservoir within a population) and (3) monitor management outcomes for deer population abundance and disease prevalence. 

Quantifying Upper Peninsula deer movements and abundance: preparing for CWD management

Primary Contact: Dr. Dean Beyer Jr., DNR Wildlife Division, Marquette, Michigan


Phone: (906) 228-6561

DNR Financial Support: $117,759 in FY19, $613,001 total.

Study Area: Upper Peninsula

Time Frame: 10/1/2017-9/30/2021

Abstract:

Chronic wasting disease (CWD) occurs in free-ranging white-tailed deer in Lower Michigan, and in our neighboring state of Wisconsin where the disease is endemic. Although wildlife managers have not documented CWD in the Upper Peninsula, managers found infected deer in two Wisconsin captive cervid facilities near the Michigan border. Officials identified the disease in a facility in Oneida County, Wisconsin, about 40 km from our Iron County border and a second positive deer in Oconto County, Wisconsin, about 50 km from our Menominee County border.

While it is not possible to predict if or when we will find CWD in the Upper Peninsula, preparations seem prudent. A scientifically based understanding of deer movements and estimates of population abundance are critical for developing management recommendations in response to CWD. Deer movements and abundance can influence the probability of disease occurrence, contact rates which can affect transmission rate, and geographic extent of an outbreak (e.g., Oyer et al. 2007, Skult et al. 2008, Webb et al. 2010). Importantly, these data take time to gather and managers need this information at the time of first discovery. Thus, waiting for a disease outbreak before gathering these data would put managers at a disadvantage. Important deer movements to understand include seasonal home ranges, migration (especially important in the Upper Peninsula), dispersal, transient, and exploratory.

Information on these movements would inform decisions on identification of CWD management zones. The current strategy is to establish a 16-km radius circle around the location of an infected cervid and include entire counties whose boundaries intersect this circle as part of the CWD management zone. Further, if results from local population surveys or other credible scientific data suggest that cervids from within the radius are likely to move beyond the management zone boundary, the boundary should be expanded accordingly. In the Upper Peninsula, deer can seasonally migrate 50 km (Van Deelen et al. 1998), with overall movements exceeding 80 km (Doepker et al. 2015). These migratory movements, as well as other movements (e.g., dispersal), are currently unknown and certainly not aligned with or contained within county boundaries. Although some information exists on deer movements in the UP, most of this work relied on tag returns that do not provide the needed level of spatial and temporal resolution to inform management responses to a disease outbreak.

Consequently, If CWD was detected in the UP, large areas would likely be under surveillance and management that would not contain infected deer and large areas with potential for infected deer would not be within the prescribed surveillance zone, rendering the current management zone less effective. The Upper Peninsula Region (UPR), Biological and Social Sciences Section (BSSS), Wildlife Health Section (WHS), and Mississippi State University (MSU) wish to develop a program to address the need for information on deer movements. The core work would entail deploying GPS collars on deer in select wintering complexes and conditional winter range (starting along WI border) and documenting movements over three years. To complete the capture and collaring work, we would work cooperatively with interested sportspersons. 







WEDNESDAY, SEPTEMBER 01, 2021 

Michigan CWD TSE Prion 211 Cases To Date


Michigan CWD TSE Prion 211 Cases To Date

Deer Tested for Chronic Wasting Disease Since Detection of First Positive Free-ranging Deer (May 2015) 


Chronic Wasting Disease (CWD) Surveillance Chronic wasting disease (CWD) is a transmissible neurological disease found in deer and elk populations that produces small lesions in brains of infected animals. As a result, CWD causes weight loss and a decline in body control. It is a species-specific disease, and there have been no cases in humans or other animals.

Currently, to determine the presence of CWD, brain and lymph node samples are taken by an accredited veterinarian after an animal dies. These samples are then submitted for testing.

As part of their operations, all privately-owned cervid (POC) facilities in Michigan are required to submit samples. The number of samples that must be submitted depends on what specific program that a producer participates in: the Chronic Wasting Disease Herd Certification Program (CWD HCP) or the Surveillance Program.

First, for the CWD HCP, all cervids 12 months of age and older that die for any reason must be tested for CWD.

Second, all facilities that are not a part of the CWD HCP must participate in the Surveillance Program. The Surveillance Program requires that all animals 12 months of age and older that die from illness, injury, or euthanasia due to disease must be tested for CWD. In addition, 25% of cervids slaughtered, hunted, or culled must be tested. This number is calculated on an annual basis. In general, all facilities that have at least one death must test at least this one animal. 

Samples for either of these programs can be submitted to a private veterinarian, the Michigan State University Veterinary Diagnostic Lab, or an MDARD drop off location. 

For more information, contact the MDARD Cervid Program.


Special Surveillance Area (SSA) If a free-ranging or privately-owned cervid (POC) tests positive for chronic wasting disease (CWD), then a buffer circle is created around that positive animal. This buffer circle is referred to as a Special Surveillance Area (SSA). POC facilities that fall within a SSA will have increased CWD testing requirements.

More specifically, if a free-ranging cervid is found to be positive for CWD, a 15-mile radius circle is created around the positive animal. And, if a POC is found to be positive for CWD, a 5-mile radius circle is created around the positive animal. Further, for both cases, the SSA extends to the entirety of the county of the infected animal and any county that the 15-mile or 5-mile circle touches. 

For a complete list of counties that are included within a particular SSA, please review the map below.


Livestock Diseases:

Disease Species Number of Animals

CWD (Chronic Wasting Disease) Cervid 46

Number of herds involved in special surveillance zones around CWD positive free-ranging deer 84 84 


MDARD CWD Confirmed at Farmed Deer Facilities in Mecosta and Montcalm Counties

... Rural Development (MDARD) has confirmed two cases of chronic wasting disease (CWD) at two separate farmed deer facilities, one ... 123 free-ranging deer from Montcalm County. "Since chronic wasting disease can significantly impact all Michigan deer, it is ...


MDARD CWD Identified in Newaygo County Farmed Deer

... Agriculture and Rural and Development (MDARD) has confirmed chronic wasting disease (CWD) in three white-tailed deer from a ... rule out exposure of any other farmed deer. "Chronic wasting disease is a serious disease affecting both farmed and ...


MDARD CWD identified in a Montcalm County farmed deer

... Rural Development (MDARD) has confirmed a case of chronic wasting disease (CWD) in a four-year-old white-tailed ... 123 free-ranging deer in Montcalm County. "As chronic wasting disease affects both farmed and free-ranging deer, MDARD ...


Michigan CWD Confirmed at Farmed Deer Facilities in Mecosta and Montcalm Counties

CWD Confirmed at Farmed Deer Facilities in Mecosta and Montcalm Counties 

For immediate release: August 11, 2021 Media contact: Jennifer Holton, 517-284-5724

LANSING, MI - The Michigan Department of Agriculture and Rural Development (MDARD) has confirmed two cases of chronic wasting disease (CWD) at two separate farmed deer facilities, one in Mecosta County and one in Montcalm County. The two infected deer, a two-year-old and a four-year-old, were discovered through routine testing as part of the state's CWD surveillance program for farmed deer.

CWD is a fatal neurological disease that affects white-tailed deer, mule deer, elk, and moose. The disease can be transmitted directly from one animal to another, as well as indirectly through the environment. While an infected deer may appear healthy for months or years, it will eventually display abnormal behavior, progressive weight loss, and physical debilitation in the latter stages of the disease.

The presence of CWD in farmed and free-ranging deer is not new to Michigan. Since 2008, and including these new cases, CWD has been detected at eight Michigan deer farms in the following counties: Kent, Mecosta (3), Montcalm (3), and Newaygo.

With free-ranging deer, CWD was first discovered in May 2015, and cases have been found across nine counties in Michigan's Upper and Lower Peninsulas. To date, while no free-ranging white-tailed deer have tested positive for CWD in Mecosta County, the disease has been detected in 123 free-ranging deer from Montcalm County. 

"Since chronic wasting disease can significantly impact all Michigan deer, it is vitally important to detect the disease as early as possible," said State Veterinarian Nora Wineland, DVM. "Early detection allows MDARD and the Michigan Department of Natural Resources to work in collaboration with farmers and hunters to stem the spread and manage this serious disease."

As part of MDARD's disease response, investigations are being conducted to rule out exposure to any other farmed deer.

Currently, there have been no reported cases of CWD infection in humans. However, as a precaution, the U.S. Centers for Disease Control and the World Health Organization recommend that infected animals should not be consumed as food by either humans or domestic animals.

More information about CWD can be found at Michigan.gov/CWD or Michigan.gov/MDARD-Cervid.

###


CWD identified in a Montcalm County farmed deer 

For immediate release: March 12, 2021 Media contact: Jessy Sielski, 517-331-1151

LANSING, MI - The Michigan Department of Agriculture and Rural Development (MDARD) has confirmed a case of chronic wasting disease (CWD) in a four-year-old white-tailed deer from a Montcalm County deer farm. The case was found through samples that were submitted for routine testing as part of the state's CWD surveillance program for farmed deer.

CWD is a fatal neurological disease that affects white-tailed deer, mule deer, elk, and moose. CWD can be transmitted directly from one animal to another, as well as indirectly through the environment. While an infected deer may appear healthy for months or years, it will eventually display abnormal behavior, progressive weight loss, and physical debilitation in the latter stages of the disease.

The discovery of CWD in farmed and free-ranging deer is not new to the state of Michigan. Since 2008, and including this new case, CWD has been detected at six Michigan deer farms in the following counties: Kent, Mecosta (2), Montcalm (2), and Newaygo.

With free-ranging deer, CWD was first discovered in May 2015, and cases have been found across nine counties in both the Upper and Lower Peninsulas. To date, CWD has been detected in 123 free-ranging deer in Montcalm County. 

"As chronic wasting disease affects both farmed and free-ranging deer, MDARD works in partnership with the Michigan Department of Natural Resources and the state's deer farmers to detect and manage this serious disease," said State Veterinarian Nora Wineland, DVM. "Due to the nature of the disease, it is imperative that farmers, hunters, DNR, and MDARD continue to work in collaboration to protect all of Michigan's deer."

As part of MDARD's disease response, an investigation will be conducted to rule out exposure of any other farmed deer.

Currently, there have been no reported cases of CWD infection in humans. However, as a precaution, the U.S. Centers for Disease Control and the World Health Organization recommend infected animals not be consumed as food by either humans or domestic animals.

More information about CWD can be found at Michigan.gov/CWD or Michigan.gov/MDARD-Cervid.

###


APPENDIX A: 2020 REPORTABLE DISEASES

Livestock Diseases: 

CWD (Chronic Wasting Disease) Cervid 46 


CWD Identified in Newaygo County Farmed Deer 

For Immediate Release: January 14, 2020 Media Contact: Jessy Sielski, 517-284-5725

LANSING, MI - The Michigan Department of Agriculture and Rural and Development (MDARD) has confirmed chronic wasting disease (CWD) in three white-tailed deer from a Newaygo County deer farm. All three deer were four-and-a-half years old. The samples were submitted for routine testing as part of the state's CWD surveillance program for farmed deer.

To date, CWD has not been detected in free-ranging deer in Newaygo County. As part of MDARD's disease response, an investigation will be conducted to rule out exposure of any other farmed deer.

"Chronic wasting disease is a serious disease affecting both farmed and free-ranging deer," said State Veterinarian Nora Wineland, DVM. "MDARD and the Michigan Department of Natural Resources work together, in partnership with the state's deer farmers, to ensure the protection of all of Michigan's deer."

Since 2008, CWD has been detected in four additional privately-owned cervid facilities from Kent, Mecosta, and Montcalm Counties. The deer farm in Newaygo County is the fifth Michigan farm in which CWD has been detected.

CWD is a fatal neurological disease that affects white-tailed deer, mule deer, elk, and moose. CWD can be transmitted directly from one animal to another, as well as indirectly through the environment. Infected animals may display abnormal behavior, progressive weight loss and physical debilitation. To date, there have been no reported cases of CWD infection in humans. However, as a precaution, the U.S. Centers for Disease Control and the World Health Organization recommend that infected animals not be consumed as food by either humans or domestic animals.

More information about CWD can be found at Michigan.gov/CWD.





Greenville man charged with violating CWD deer requirements

By Elisabeth Waldon | on February 03, 2021

Eric Snyder

EUREKA TOWNSHIP — A Greenville man is facing half a dozen charges related to his alleged improper handling of deer with chronic wasting disease (CWD).

Eric David Snyder, 51, is charged with three counts of animal industry acts (privately owned cervidae) two counts of animal industry acts (felony violation) and one count of animals burial.

According to Montcalm County Prosecutor Andrea Krause, the alleged crimes occurred between March 2019 and February 2020. The Department of Natural Resources investigated, however, Snyder wasn’t charged until December 2020 and he wasn’t arraigned until Jan. 21. Krause said the coronavirus pandemic likely played a role in the delay.

According to Krause, Snyder owned Fieldview Whitetails, a deer farm/ranch in Eureka Township.

 “He had a deer test positive for CWD,” Krause said. “(Snyder) dumped the deer outside the farm in violation of the law. He also violated a quarantine of the other deer he had on his farm.”

A deer with CWD in Montcalm County was discovered in October 2017 and as a precaution in January 2018, all privately owned deer facilities were put into mandatory quarantine if they were within 15 miles of a deer that tested positive, according to Krause. In March 2019, a deer at Snyder’s farm was discovered to have CWD, and a follow-up investigation later that month discovered the alleged violations at the farm, according to Krause.

Snyder is being represented by attorney Jeff Crampton. If convicted, Snyder faces to from 90 days to five years prison and/or fines and costs.

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MONDAY, JUNE 28, 2021 

Michigan Total CWD Positive/Suspect Positive Deer 209 Cases To Date


FRIDAY, NOVEMBER 27, 2020 

Michigan, to date, CWD TSE Prion has been detected in 197 cervid 


SUNDAY, OCTOBER 11, 2020 

Michigan Chronic Wasting Disease CWD TSE Prion increases to 191 positive to date


TUESDAY, SEPTEMBER 22, 2020 

Michigan CWD TSE Prion 189 Positive To Date UPDATE September 2020


WEDNESDAY, MARCH 25, 2020 

Michigan CWD TSE Prion Total Suspect Positive Deer Moves Up To 188 with total deer tested 80,687 to date



THURSDAY, JANUARY 30, 2020 

Michigan CWD TSE Prion Total Suspect Positive Deer Jumps To 181 to date


MONDAY, JANUARY 27, 2020 

Michigan CWD TSE Prion MDARD 3 positive white-tailed deer from a Newaygo County deer farm depopulation and quarantine efforts update?


TUESDAY, JANUARY 14, 2020 

Michigan MDARD has confirmed chronic wasting disease (CWD) in 3 white-tailed deer from a Newaygo County deer farm


TUESDAY, JANUARY 07, 2020 

Michigan Total CWD TSE Prion Positive Suspect-Positive Deer Jump To 174 confirmed to date


THURSDAY, DECEMBER 12, 2019 
Michigan Total CWD TSE Prion Positive Suspect-Positive Deer Jump To 162 confirmed to date


FRIDAY, NOVEMBER 22, 2019 

Michigan Total CWD TSE Prion Positive/Suspect-Positive Deer 140 To Date


WEDNESDAY, NOVEMBER 06, 2019 

Michigan Total CWD TSE Prion Positive, Suspect Positive, Deer 136 To Date


2019 CWD Testing Goals and Results as of October 18, 2019


THURSDAY, OCTOBER 24, 2019 

Michigan DNR reports CWD-positive deer in Hamilton Township, Gratiot County


THURSDAY, OCTOBER 24, 2019 

Michigan DNR reports CWD-positive deer in Hamilton Township, Gratiot County


SATURDAY, OCTOBER 05, 2019 

Michigan MSU SCIENTISTS ARE TESTING A FASTER WAY TO DETECT CHRONIC WASTING DISEASE


SUNDAY, SEPTEMBER 22, 2019 

Michigan TWO MORE CWD TSE PRION POSITIVES Total Now At 124 Positive


TUESDAY, SEPTEMBER 17, 2019 

Michigan House Bill 4687 State Legislators Turn To Draft Dodger Ted Nugent To Make Scientific Decisions over DNR on CWD TSE Prion


SATURDAY, AUGUST 24, 2019 
Michigan Chronic Wasting Disease CWD TSE Prion Two More Cases Total 122 To Date
THURSDAY, MAY 23, 2019 

Michigan Osceola County deer farm/ranch owner arraigned on several violations

THURSDAY, MAY 09, 2019 

Michigan CWD TSE Prion increases to 120 Cases to Date


THURSDAY, MARCH 28, 2019 

Michigan CWD Identified in a Montcalm County Farmed Deer


March 30, 2018

Contact: Lt. David Shaw, 616-218-3762

Mecosta County man sentenced following DNR investigation

Game ranch owner falsified information related to chronic wasting disease testing

A Mecosta County game ranch owner has been sentenced on charges resulting from an investigation by the Michigan Department of Natural Resources Law Enforcement Division, in cooperation with the Michigan Department of Agriculture and Rural Development.

Lester Jay Gemmen, 64, of Morley was charged with providing false information regarding the origin of two deer heads that were submitted for disease testing, and for failing to properly maintain fencing at the Super G Ranch. The ranch is a privately owned cervid (POC) facility, a designation that includes game ranches and hunting ranches.

He was sentenced by the 77th District Court to 60 days in jail for each count, ordered to pay $775 in fines and costs and must perform 80 hours of community service.

The investigation began in 2017 after two of the six deer heads submitted by Gemmen tested positive for chronic wasting disease (CWD).

“I commend the detectives from our Special Investigations Unit and our field conservation officers for their thorough, professional approach to this investigation,” said 1st Lt. David Shaw, supervisor of the Special Investigations Unit of the DNR Law Enforcement Division.

The facility’s remaining deer were depopulated and tested, but no further evidence of CWD was found. The facility remains under quarantine, currently preventing ownership of farmed cervids.

The Privately Owned Cervid Program is jointly managed by the DNR and MDARD. There is mandatory CWD testing in all registered herds in Michigan, under the oversight of MDARD. The DNR oversees POC registration and performs inspections of POC facilities. Proper maintenance of POC facilities is critical to protecting Michigan’s free-ranging and privately owned cervid herds.

CWD is a fatal central nervous system disease that affects white-tailed deer, mule deer, elk and moose. It attacks the brain of infected animals, creating small lesions in the brain, which result in death. It is transmitted through direct animal-to-animal contact or by contact with saliva, urine, feces, blood, carcass parts of an infected animal or infected soil. To date, there have been no reported cases of CWD infection in humans. However, as a precaution, the U.S. Centers for Disease Control and Prevention and the World Health Organization recommend that infected animals not be consumed as food by humans or domestic animals.

Since May 2015, CWD-positive deer have been found in Michigan. As of mid-March 2018, 57 free-ranging deer have tested positive for the disease. CWD has not been found in the Upper Peninsula, though it has been discovered in Wisconsin, approximately 40 miles from the western Upper Peninsula border.

The DNR is working with stakeholders to address the status of CWD in Michigan. In the coming weeks, the DNR and the Michigan Natural Resources Commission will host a series of public engagement meetings across the state on CWD. The sessions will provide hunters, business owners and residents with opportunities to share their ideas and observations.

In addition, the DNR, NRC and MDARD are evaluating recommendations from the CWD Working Group, which was created after last year’s CWD Symposium. The symposium brought national and international experts to Michigan to discuss CWD. During the coming months, the DNR, NRC and MDARD will work with stakeholders to develop new CWD regulation recommendations.

Visit www.michigan.gov/cwd for more information about the disease, preventive measures and the public meeting schedule.


SATURDAY, MARCH 03, 2018 

Michigan-Sportsman.com Bans Terry S. Singeltary Sr. For Speaking about Chronic Wasting Disease CWD TSE Prion 




Voluntary Chronic Wasting Disease Herd Certification Program Annual Update, FY2020

Last Modified: Feb 9, 2021

U.S. Department of Agriculture

Animal and Plant Health Inspection Service (APHIS) Veterinary Services

Annual Update from the Cervid Health Team

Voluntary Chronic Wasting Disease Herd Certification Program (HCP)

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, herds participating in the HCP 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 farmed cervids from enrolled herds certified as low risk for CWD may move interstate. FY 2020 marks the eighth year that Approved States have submitted their CWD HCP annual reports to APHIS.

The current Cervid Health Program staff officers are as follows: Dr. Mark Lyons, Dr. Jennifer Siembieda, and Dr. 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 Summary of CW Detections

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 ARS, USGS, University of WI, and NIH for tissue sample testing using RT-QuIC

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

snip...

Voluntary Chronic Wasting Disease Herd Certification Program Annual Update, FY2020


Cervids: CWD Voluntary Herd Certification Program

Last Modified: Jun 29, 2021


CWD status of captive herds


SUNDAY, OCTOBER 24, 2021 

Voluntary Chronic Wasting Disease Herd Certification Program Annual Update, FY2020


SATURDAY, DECEMBER 04, 2021 

TPWD CWD TSE PRION TRACKER UPDATE TEXAS 270 CONFIRMED TO DATE POSTIVE CAPTIVE AND WILD


SATURDAY, NOVEMBER 06, 2021 

Texas adopts new management rules for chronic wasting disease in deer Nov 6, 2021


TPWD CWD TSE PRION TRACKER UPDATE TEXAS 270 CONFIRMED TO DATE POSTIVE CAPTIVE AND WILD

2021-11-18 Free Range Medina N/A White-tailed Deer M 3.5

2021-11-04 Free Range El Paso N/A Mule Deer F 4.5

2021-10-18 Breeder Deer Medina Facility #4 White-tailed Deer M 4

2021-10-12 Breeder Deer Hunt Facility #9 White-tailed Deer F 8.189041096

2021-10-12 Breeder Deer Uvalde Facility #8 White-tailed Deer M 1.208219178

2021-10-12 Breeder Deer Uvalde Facility #8 White-tailed Deer M 1.21369863

2021-10-12 Breeder Deer Uvalde Facility #8 White-tailed Deer M 1.205479452

2021-10-12 Breeder Deer Uvalde Facility #8 White-tailed Deer M 2.208219178

2021-10-12 Breeder Deer Uvalde Facility #8 White-tailed Deer M 2.117808219

2021-10-08 Breeder Deer Duval Facility #13 White-tailed Deer F 3.238356164

2021-10-08 Breeder Deer Medina Facility #4 White-tailed Deer F 2.260273973

2021-09-14 Breeder Deer Medina Facility #4 White-tailed Deer F 6.205479452

SNIP...SEE ALL;


“Regarding the current situation involving CWD in permitted deer breeding facilities, TPWD records indicate that within the last five years, the seven CWD-positive facilities transferred a total of 2,530 deer to 270 locations in 102 counties and eight locations in Mexico (the destinations included 139 deer breeding facilities, 118 release sites, five Deer Management Permit sites, and three nursing facilities).'' ...

It is apparent that prior to the recent emergency rules, the CWD detection rules were ineffective at detecting CWD earlier in the deer breeding facilities where it was eventually discovered and had been present for some time; this creates additional concern regarding adequate mitigation of the risk of transferring CWD-positive breeder deer to release sites where released breeder deer come into contact with free-ranging deer...

Commission Agenda Item No. 5 Exhibit B

DISEASE DETECTION AND RESPONSE RULES

PROPOSAL PREAMBLE

1. Introduction. 

snip...

 A third issue is the accuracy of mortality reporting. Department records indicate that for each of the last five years an average of 26 deer breeders have reported a shared total of 159 escapes. Department records for the same time period indicate an average of 31 breeding facilities reported a shared total of 825 missing deer (deer that department records indicate should be present in the facility, but cannot be located or verified). 



Listen here;

Nov 3, 2021


Nov 4, 2021


Counties where CWD Exposed Deer were Released, September 2021


Number of CWD Exposed Deer Released by County, September 2021


Oh, Deer, CWD, Heading Off a Wildlife Epidemic Texas Real Estate Research Center TAMU

Texas A & M University

Texas Real Estate Research Center 

Oh, Deer

Heading Off a Wildlife Epidemic

Charles E. Gilliland (Aug 18, 2021)

The Takeaway

Landowners in certain parts of the state need to be aware of chronic wasting disease, which can greatly reduce the number of deer. While there are no known cures or ways to eradicate the disease, the Texas Parks and Wildlife Department is taking measures to reduce its spread.

snip...

Because the spread of CWD is evolving, regulations can change quickly. Therefore, anyone involved in hunting activity should consult the most recent Outdoor Annual for the latest regulations. To reduce the chances of spreading the disease, TPWD regulations also restrict the movement of live deer from CWD zones.

Impact on Rural Landowners CWD poses a significant threat to the future of hunting in Texas. Deer population declines of 45 and 50 percent have been documented in Colorado and Wyoming. A broad infection of Texas deer populations resulting in similar population impacts would inflict severe economic damage to rural communities and could negatively impact land markets. Specifically, those landowners seeking to establish a thriving herd of deer could avoid buying in areas with confirmed CWD infections.

As they do with anthrax-susceptible properties, land brokers may find it advisable to inquire about the status of CWD infections on properties that they present for sale. Prospective buyers should also investigate the status of the wildlife on prospective properties. In addition, existing landowners should monitor developments as TPWD crafts management strategies to identify and contain this deadly disease. 

____________________

Dr. Gilliland (c-gilliland@tamu.edu) is a research economist with the Texas Real Estate Research Center at Texas A&M University.


FRIDAY, FEBRUARY 18, 2022 

Texas TPWD DIVISION 2 CHRONIC WASTING DISEASE COMPREHENSIVE RULES 


THE 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. 

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 with. 

***> that’s what’s so worrisome about Iatrogenic mode of transmission, a simple autoclave will not kill this TSE prion agent.

1: J Neurol Neurosurg Psychiatry 1994 Jun;57(6):757-8 

***> 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. 

PMID: 8006664 [PubMed - indexed for MEDLINE] 


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/

MONDAY, APRIL 19, 2021

Evaluation of the application for new alternative biodiesel production process for rendered fat including Category 1 animal by-products (BDI-RepCat® process, AT) ???

https://transmissiblespongiformencephalopathy.blogspot.com/2021/04/evaluation-of-application-for-new.html

Detection of protease-resistant cervid prion protein in water from a CWD-endemic area 

https://www.ncbi...nlm.nih.gov/pmc/articles/PMC2802782/pdf/prion0303_0171.pdf

A Quantitative Assessment of the Amount of Prion Diverted to Category 1 Materials and Wastewater During Processing 

http://onlinelibrary.wiley.com/doi/10.1111/j.1539-6924.2012.01922.x/abstract

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


5 or 6 years quarantine is NOT LONG ENOUGH FOR CWD TSE PRION !!!

QUARANTINE NEEDS TO BE 21 YEARS FOR CWD TSE PRION !

FRIDAY, APRIL 30, 2021 

Should Property Evaluations Contain Scrapie, CWD, TSE PRION Environmental Contamination of the land?

***> 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...

Scrapie Agent (Strain 263K) Can Transmit Disease via the Oral Route after Persistence in Soil over Years

Published: May 9, 2007

snip...

Our results showed that 263K scrapie agent can persist in soil at least over 29 months. Strikingly, not only the contaminated soil itself retained high levels of infectivity, as evidenced by oral administration to Syrian hamsters, but also feeding of aqueous soil extracts was able to induce disease in the reporter animals. We could also demonstrate that PrPSc in soil, extracted after 21 months, provides a catalytically active seed in the protein misfolding cyclic amplification (PMCA) reaction. PMCA opens therefore a perspective for considerably improving the detectability of prions in soil samples from the field.

snip...


***> This is very likely to have parallels with control efforts for CWD in cervids. <***

Paper

Rapid recontamination of a farm building occurs after attempted prion removal

Kevin Christopher Gough BSc (Hons), PhD Claire Alison Baker BSc (Hons) Steve Hawkins MIBiol Hugh Simmons BVSc, MRCVS, MBA, MA Timm Konold DrMedVet, PhD, MRCVS … See all authors 

First published: 19 January 2019 https://doi.org/10.1136/vr.105054

Abstract

The transmissible spongiform encephalopathy scrapie of sheep/goats and chronic wasting disease of cervids are associated with environmental reservoirs of infectivity. Preventing environmental prions acting as a source of infectivity to healthy animals is of major concern to farms that have had outbreaks of scrapie and also to the health management of wild and farmed cervids. Here, an efficient scrapie decontamination protocol was applied to a farm with high levels of environmental contamination with the scrapie agent. Post‐decontamination, no prion material was detected within samples taken from the farm buildings as determined using a sensitive in vitro replication assay (sPMCA). A bioassay consisting of 25 newborn lambs of highly susceptible prion protein genotype VRQ/VRQ introduced into this decontaminated barn was carried out in addition to sampling and analysis of dust samples that were collected during the bioassay. Twenty‐four of the animals examined by immunohistochemical analysis of lymphatic tissues were scrapie‐positive during the bioassay, samples of dust collected within the barn were positive by month 3. 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 scrapiepositive 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.



***> 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

Gudmundur Georgsson1, Sigurdur Sigurdarson2, Paul Brown3

http://www.microbiologyresearch.org/docserver/fulltext/jgv/87/12/3737.pdf?expires=1540908280&id=id&accname=guest&checksum=ED0572E1E5B272C100A32212A3E3761A


Front. Vet. Sci., 14 September 2015 | https://doi.org/10.3389/fvets.2015.00032

Objects in contact with classical scrapie sheep act as a reservoir for scrapie transmission

imageTimm Konold1*, imageStephen A. C. Hawkins2, imageLisa C. Thurston3, imageBen C. Maddison4, imageKevin C. Gough5, imageAnthony Duarte1 and imageHugh A. Simmons1

1Animal Sciences Unit, Animal and Plant Health Agency Weybridge, Addlestone, UK

2Pathology Department, Animal and Plant Health Agency Weybridge, Addlestone, UK

3Surveillance and Laboratory Services, Animal and Plant Health Agency Penrith, Penrith, UK

4ADAS UK, School of Veterinary Medicine and Science, University of Nottingham, Sutton Bonington, UK

5School of Veterinary Medicine and Science, University of Nottingham, Sutton Bonington, UK

Classical scrapie is an environmentally transmissible prion disease of sheep and goats. Prions can persist and remain potentially infectious in the environment for many years and thus pose a risk of infecting animals after re-stocking. In vitro studies using serial protein misfolding cyclic amplification (sPMCA) have suggested that objects on a scrapie-affected sheep farm could contribute to disease transmission. This in vivo study aimed to determine the role of field furniture (water troughs, feeding troughs, fencing, and other objects that sheep may rub against) used by a scrapie-infected sheep flock as a vector for disease transmission to scrapie-free lambs with the prion protein genotype VRQ/VRQ, which is associated with high susceptibility to classical scrapie. When the field furniture was placed in clean accommodation, sheep became infected when exposed to either a water trough (four out of five) or to objects used for rubbing (four out of seven). This field furniture had been used by the scrapie-infected flock 8 weeks earlier and had previously been shown to harbor scrapie prions by sPMCA. Sheep also became infected (20 out of 23) through exposure to contaminated field furniture placed within pasture not used by scrapie-infected sheep for 40 months, even though swabs from this furniture tested negative by PMCA. This infection rate decreased (1 out of 12) on the same paddock after replacement with clean field furniture. Twelve grazing sheep exposed to field furniture not in contact with scrapie-infected sheep for 18 months remained scrapie free. The findings of this study highlight the role of field furniture used by scrapie-infected sheep to act as a reservoir for disease re-introduction although infectivity declines considerably if the field furniture has not been in contact with scrapie-infected sheep for several months. PMCA may not be as sensitive as VRQ/VRQ sheep to test for environmental contamination.

snip...

Discussion 

Classical scrapie is an environmentally transmissible disease because it has been reported in naïve, supposedly previously unexposed sheep placed in pastures formerly occupied by scrapie-infected sheep (4, 19, 20). 

Although the vector for disease transmission is not known, soil is likely to be an important reservoir for prions (2) where – based on studies in rodents – prions can adhere to minerals as a biologically active form (21) and remain infectious for more than 2 years (22). 

Similarly, chronic wasting disease (CWD) has re-occurred in mule deer housed in paddocks used by infected deer 2 years earlier, which was assumed to be through foraging and soil consumption (23). 

Our study suggested that the risk of acquiring scrapie infection was greater through exposure to contaminated wooden, plastic, and metal surfaces via water or food troughs, fencing, and hurdles than through grazing. 

Drinking from a water trough used by the scrapie flock was sufficient to cause infection in sheep in a clean building. 

Exposure to fences and other objects used for rubbing also led to infection, which supported the hypothesis that skin may be a vector for disease transmission (9). 

The risk of these objects to cause infection was further demonstrated when 87% of 23 sheep presented with PrPSc in lymphoid tissue after grazing on one of the paddocks, which contained metal hurdles, a metal lamb creep and a water trough in contact with the scrapie flock up to 8 weeks earlier, whereas no infection had been demonstrated previously in sheep grazing on this paddock, when equipped with new fencing and field furniture. 

When the contaminated furniture and fencing were removed, the infection rate dropped significantly to 8% of 12 sheep, with soil of the paddock as the most likely source of infection caused by shedding of prions from the scrapie-infected sheep in this paddock up to a week earlier. 

This study also indicated that the level of contamination of field furniture sufficient to cause infection was dependent on two factors: stage of incubation period and time of last use by scrapie-infected sheep. 

Drinking from a water trough that had been used by scrapie sheep in the predominantly pre-clinical phase did not appear to cause infection, whereas infection was shown in sheep drinking from the water trough used by scrapie sheep in the later stage of the disease. 

It is possible that contamination occurred through shedding of prions in saliva, which may have contaminated the surface of the water trough and subsequently the water when it was refilled. 

Contamination appeared to be sufficient to cause infection only if the trough was in contact with sheep that included clinical cases. 

Indeed, there is an increased risk of bodily fluid infectivity with disease progression in scrapie (24) and CWD (25) based on PrPSc detection by sPMCA. 

Although ultraviolet light and heat under natural conditions do not inactivate prions (26), furniture in contact with the scrapie flock, which was assumed to be sufficiently contaminated to cause infection, did not act as vector for disease if not used for 18 months, which suggest that the weathering process alone was sufficient to inactivate prions. 

PrPSc detection by sPMCA is increasingly used as a surrogate for infectivity measurements by bioassay in sheep or mice. 

In this reported study, however, the levels of PrPSc present in the environment were below the limit of detection of the sPMCA method, yet were still sufficient to cause infection of in-contact animals. 

In the present study, the outdoor objects were removed from the infected flock 8 weeks prior to sampling and were positive by sPMCA at very low levels (2 out of 37 reactions). 

As this sPMCA assay also yielded 2 positive reactions out of 139 in samples from the scrapie-free farm, the sPMCA assay could not detect PrPSc on any of the objects above the background of the assay. 

False positive reactions with sPMCA at a low frequency associated with de novo formation of infectious prions have been reported (27, 28). 

This is in contrast to our previous study where we demonstrated that outdoor objects that had been in contact with the scrapie-infected flock up to 20 days prior to sampling harbored PrPSc that was detectable by sPMCA analysis [4 out of 15 reactions (12)] and was significantly more positive by the assay compared to analogous samples from the scrapie-free farm. 

This discrepancy could be due to the use of a different sPMCA substrate between the studies that may alter the efficiency of amplification of the environmental PrPSc. 

In addition, the present study had a longer timeframe between the objects being in contact with the infected flock and sampling, which may affect the levels of extractable PrPSc. 

Alternatively, there may be potentially patchy contamination of this furniture with PrPSc, which may have been missed by swabbing. 

The failure of sPMCA to detect CWD-associated PrP in saliva from clinically affected deer despite confirmation of infectivity in saliva-inoculated transgenic mice was associated with as yet unidentified inhibitors in saliva (29), and it is possible that the sensitivity of sPMCA is affected by other substances in the tested material. 

In addition, sampling of amplifiable PrPSc and subsequent detection by sPMCA may be more difficult from furniture exposed to weather, which is supported by the observation that PrPSc was detected by sPMCA more frequently in indoor than outdoor furniture (12). 

A recent experimental study has demonstrated that repeated cycles of drying and wetting of prion-contaminated soil, equivalent to what is expected under natural weathering conditions, could reduce PMCA amplification efficiency and extend the incubation period in hamsters inoculated with soil samples (30). 

This seems to apply also to this study even though the reduction in infectivity was more dramatic in the sPMCA assays than in the sheep model. 

Sheep were not kept until clinical end-point, which would have enabled us to compare incubation periods, but the lack of infection in sheep exposed to furniture that had not been in contact with scrapie sheep for a longer time period supports the hypothesis that prion degradation and subsequent loss of infectivity occurs even under natural conditions. 

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. 

These results suggest that the VRQ/VRQ sheep model may be more sensitive than sPMCA for the detection of environmentally associated scrapie, and suggest that extremely low levels of scrapie contamination are able to cause infection in susceptible sheep genotypes. 

Keywords: classical scrapie, prion, transmissible spongiform encephalopathy, sheep, field furniture, reservoir, serial protein misfolding cyclic amplification 

http://journal.frontiersin.org/article/10.3389/fvets.2015.00032/full

***> 172. Establishment of PrPCWD extraction and detection methods in the farm soil

Kyung Je Park, Hoo Chang Park, In Soon Roh, Hyo Jin Kim, Hae-Eun Kang and Hyun Joo Sohn

Foreign Animal Disease Division, Animal and Plant Quarantine Agency, Gimcheon, Gyeongsangbuk-do, Korea

Conclusions: Our studies showed that PrPCWD persist in 0.001% CWD contaminated soil for at least 4 year and natural CWD-affected farm soil. When cervid reintroduced into CWD outbreak farm, the strict decontamination procedures of the infectious agent should be performed in the environment of CWD-affected cervid habitat.

https://www.tandfonline.com/doi/full/10.1080/19336896.2019.1615197

***> CONGRESSIONAL ABSTRACTS PRION CONFERENCE 2018
P69 Experimental transmission of CWD from white-tailed deer to co-housed reindeer 

Mitchell G (1), Walther I (1), Staskevicius A (1), Soutyrine A (1), Balachandran A (1) 

(1) National & OIE Reference Laboratory for Scrapie and CWD, Canadian Food Inspection Agency, Ottawa, Ontario, Canada. 

Chronic wasting disease (CWD) continues to be detected in wild and farmed cervid populations of North America, affecting predominantly white-tailed deer, mule deer and elk. Extensive herds of wild caribou exist in northern regions of Canada, although surveillance has not detected the presence of CWD in this population. Oral experimental transmission has demonstrated that reindeer, a species closely related to caribou, are susceptible to CWD. Recently, CWD was detected for the first time in Europe, in wild Norwegian reindeer, advancing the possibility that caribou in North America could also become infected. Given the potential overlap in habitat between wild CWD-infected cervids and wild caribou herds in Canada, we sought to investigate the horizontal transmissibility of CWD from white-tailed deer to reindeer. 

Two white-tailed deer were orally inoculated with a brain homogenate prepared from a farmed Canadian white-tailed deer previously diagnosed with CWD. Two reindeer, with no history of exposure to CWD, were housed in the same enclosure as the white-tailed deer, 3.5 months after the deer were orally inoculated. The white-tailed deer developed clinical signs consistent with CWD beginning at 15.2 and 21 months post-inoculation (mpi), and were euthanized at 18.7 and 23.1 mpi, respectively. Confirmatory testing by immunohistochemistry (IHC) and western blot demonstrated widespread aggregates of pathological prion protein (PrPCWD) in the central nervous system and lymphoid tissues of both inoculated white-tailed deer. Both reindeer were subjected to recto-anal mucosal associated lymphoid tissue (RAMALT) biopsy at 20 months post-exposure (mpe) to the white-tailed deer. The biopsy from one reindeer contained PrPCWD confirmed by IHC. This reindeer displayed only subtle clinical evidence of disease prior to a rapid decline in condition requiring euthanasia at 22.5 mpe. Analysis of tissues from this reindeer by IHC revealed widespread PrPCWD deposition, predominantly in central nervous system and lymphoreticular tissues. Western blot molecular profiles were similar between both orally inoculated white-tailed deer and the CWD positive reindeer. Despite sharing the same enclosure, the other reindeer was RAMALT negative at 20 mpe, and PrPCWD was not detected in brainstem and lymphoid tissues following necropsy at 35 mpe. Sequencing of the prion protein gene from both reindeer revealed differences at several codons, which may have influenced susceptibility to infection. 

Natural transmission of CWD occurs relatively efficiently amongst cervids, supporting the expanding geographic distribution of disease and the potential for transmission to previously naive populations. The efficient horizontal transmission of CWD from white-tailed deer to reindeer observed here highlights the potential for reindeer to become infected if exposed to other cervids or environments infected with CWD. 

SOURCE REFERENCE 2018 PRION CONFERENCE ABSTRACT

Research Project: TRANSMISSION, DIFFERENTIATION, AND PATHOBIOLOGY OF TRANSMISSIBLE SPONGIFORM ENCEPHALOPATHIES Location: Virus and Prion Research

Title: Horizontal transmission of chronic wasting disease in reindeer

Author

item MOORE, SARAH - ORISE FELLOW item KUNKLE, ROBERT item WEST GREENLEE, MARY - IOWA STATE UNIVERSITY item Nicholson, Eric item RICHT, JUERGEN item HAMIR, AMIRALI item WATERS, WADE item Greenlee, Justin

Submitted to: Emerging Infectious Diseases

Publication Type: Peer Reviewed Journal

Publication Acceptance Date: 8/29/2016

Publication Date: 12/1/2016

Citation: Moore, S., Kunkle, R., Greenlee, M., Nicholson, E., Richt, J., Hamir, A., Waters, W., Greenlee, J. 2016. Horizontal transmission of chronic wasting disease in reindeer. Emerging Infectious Diseases. 22(12):2142-2145. doi:10.3201/eid2212.160635.

Interpretive Summary: Chronic wasting disease (CWD) is a fatal neurodegenerative disease that occurs in farmed and wild cervids (deer and elk) of North America and was recently diagnosed in a single free-ranging reindeer (Rangifer tarandus tarandus) in Norway. CWD is a transmissible spongiform encephalopathy (TSE) that is caused by infectious proteins called prions that are resistant to various methods of decontamination and environmental degradation. Little is known about the susceptibility of or potential for transmission amongst reindeer. In this experiment, we tested the susceptibility of reindeer to CWD from various sources (elk, mule deer, or white-tailed deer) after intracranial inoculation and tested the potential for infected reindeer to transmit to non-inoculated animals by co-housing or housing in adjacent pens. Reindeer were susceptible to CWD from elk, mule deer, or white-tailed deer sources after experimental inoculation. Most importantly, non-inoculated reindeer that were co-housed with infected reindeer or housed in pens adjacent to infected reindeer but without the potential for nose-to-nose contact also developed evidence of CWD infection. This is a major new finding that may have a great impact on the recently diagnosed case of CWD in the only remaining free-ranging reindeer population in Europe as our findings imply that horizontal transmission to other reindeer within that herd has already occurred. Further, this information will help regulatory and wildlife officials developing plans to reduce or eliminate CWD and cervid farmers that want to ensure that their herd remains CWD-free, but were previously unsure of the potential for reindeer to transmit CWD.

Technical Abstract: Chronic wasting disease (CWD) is a naturally-occurring, fatal prion disease of cervids. Reindeer (Rangifer tarandus tarandus) are susceptible to CWD following oral challenge, and CWD was recently reported in a free-ranging reindeer of Norway. Potential contact between CWD-affected cervids and Rangifer species that are free-ranging or co-housed on farms presents a potential risk of CWD transmission. The aims of this study were to 1) investigate the transmission of CWD from white-tailed deer (Odocoileus virginianus; CWDwtd), mule deer (Odocoileus hemionus; CWDmd), or elk (Cervus elaphus nelsoni; CWDelk) to reindeer via the intracranial route, and 2) to assess for direct and indirect horizontal transmission to non-inoculated sentinels. Three groups of 5 reindeer fawns were challenged intracranially with CWDwtd, CWDmd, or CWDelk. Two years after challenge of inoculated reindeer, non-inoculated negative control reindeer were introduced into the same pen as the CWDwtd inoculated reindeer (direct contact; n=4) or into a pen adjacent to the CWDmd inoculated reindeer (indirect contact; n=2). Experimentally inoculated reindeer were allowed to develop clinical disease. At death/euthanasia a complete necropsy examination was performed, including immunohistochemical testing of tissues for disease-associated CWD prion protein (PrPcwd). Intracranially challenged reindeer developed clinical disease from 21 months post-inoculation (months PI). PrPcwd was detected in 5 out of 6 sentinel reindeer although only 2 out of 6 developed clinical disease during the study period (< 57 months PI). We have shown that reindeer are susceptible to CWD from various cervid sources and can transmit CWD to naïve reindeer both directly and indirectly.

https://www.ars.usda.gov/research/publications/publication/?seqNo115=328261

Infectivity surviving ashing to 600*C is (in my opinion) degradable but infective. based on Bown & Gajdusek, (1991), landfill and burial may be assumed to have a reduction factor of 98% (i.e. a factor of 50) over 3 years. CJD-infected brain-tissue remained infectious after storing at room-temperature for 22 months (Tateishi et al, 1988). Scrapie agent is known to remain viable after at least 30 months of desiccation (Wilson et al, 1950). and pastures that had been grazed by scrapie-infected sheep still appeared to be contaminated with scrapie agent three years after they were last occupied by sheep (Palsson, 1979).

http://europa.eu.int/comm/food/fs/sc/ssc/out58_en.pdf

Dr. Paul Brown Scrapie Soil Test BSE Inquiry Document

https://web.archive.org/web/20090505211734/http://www.bseinquiry.gov.uk/files/sc/Seac07/tab03.pdf

Pathogens. 2020 Apr; 9(4): 311.

Published online 2020 Apr 23. doi: 10.3390/pathogens9040311

PMCID: PMC7238116

PMID: 32340296

Long-Term Incubation PrPCWD with Soils Affects Prion Recovery but Not Infectivity

Alsu Kuznetsova,1 Debbie McKenzie,2 Catherine Cullingham,3 and Judd M. Aiken1,*

Abstract

Chronic wasting disease (CWD) is a contagious prion disease of cervids. The infectious agent is shed from animals at the preclinical and clinical stages of disease where it persists in the environment as a reservoir of CWD infectivity. In this study, we demonstrate that long-term incubation of CWD prions (generated from tg-mice infected with deer or elk prions) with illite, montmorillonite (Mte) and whole soils results in decreased recovery of PrPCWD, suggesting that binding becomes more avid and irreversible with time. This continual decline of immunoblot PrPCWD detection did not correlate with prion infectivity levels. Bioassay showed no significant differences in incubation periods between mice inoculated with 1% CWD brain homogenate (BH) and with the CWD-BH pre-incubated with quartz or Luvisolic Ae horizon for 1 or 30 weeks. After 55 weeks incubation with Chernozem and Luvisol, bound PrPCWD was not detectable by immunoblotting but remained infectious. This study shows that although recovery of PrPCWD bound to soil minerals and whole soils with time become more difficult, prion infectivity is not significantly altered. Detection of prions in soil is, therefore, not only affected by soil type but also by length of time of the prion–soil interaction.

snip...

4. Conclusions

The binding of prions to soil minerals and other soil constituents impacts PrPCWD recovery. During extended incubation with soils, PrP signal on immunoblots continuously declined until it was no longer detectable after 25 weeks in soils with loamy-clay texture and Mte minerology. PrPCWD infectivity did not, however, decrease after 30 weeks incubation with quartz and the Luvisolic Ae soil horizon. At 55 weeks incubation in Chernozem and Luvisol, CWD-BH remained infectious. We studied a wide variety of soil types (from prairie, mountain and boreal regions) and showed decreased PrPCWD signal recovery (as measured by immunoblotting) with retention of infectivity. The decrease in PrPCWD recovery was particularly dramatic in soils from the prairie region. Regardless of soil minerology, texture and humus content, detection of PrPCWD in environmental soil samples is a challenge after long-term incubation. These findings provide important information on the behavior of prions in natural environments, but complicate analysis of environmental samples.

Keywords: prion protein, soil, CWD, prolonged incubation, CWD infectivity, prion detection


Prion. 2012 Jul 1; 6(3): 302–308. doi: 10.4161/pri.20025 PMCID: PMC3399538 PMID: 22561162

Temperature influences the interaction of ruminant PrPTSE with soil

Ben C. Maddison, 1 Jonathan P. Owen, 1 Maged A. Taema, 2 George Shaw, 3 and Kevin C. Gough 2 , *

Abstract

Ovine scrapie and cervid chronic wasting disease can be transmitted in the absence of animal-to-animal contact, and environmental reservoirs of infectivity have been implicated in their spread and persistence. Investigating environmental factors that influence the interaction of disease-associated PrP with soils is imperative to understanding what is likely to be the complex role of soil in disease transmission. Here, we describe the effects of soil temperature on the binding/desorption and persistence of both ovine scrapie- and bovine BSE-PrPTSE. Binding of PrPTSE to a sandy loam soil at temperatures of 4°C, 8–12°C and 25–30°C demonstrated that an increase in temperature resulted in (1) a decrease in the amount of PrPTSE recovered after 24 h of interaction with soil, (2) an increase in the amount of N-terminal cleavage of the prion protein over 11 d and (3) a decrease in the persistence of PrPTSE on soil over an 18 mo period.

snip...

In the present study we investigated the effects of soil temperature in the range 4°C to 30°C on the interaction of BSE- and scrapie-PrPTSE with a complex soil matrix. Lower soil temperatures resulted in increased levels of PrPTSE recovery and persistence over an 18-mo incubation period. A low soil temperature also resulted in less cleavage of the N-terminal domain of PrPTSE after an 11-d interaction. These effects of temperature on PrPTSE-soil interaction were likely to be exerted through both microbial activity and abiotic cleavage mechanisms. Together, the data indicate that for the recoverable fraction of PrPTSE, soils at lower temperature may release increased levels of PrPTSE.

A recent study using transmissible mink encephalopathy reported a correlation between the level of desorption of PrPTSE from soil and the infectivity titer of the sample.25 If such a correlation is also true for ovine scrapie and bovine BSE, the data presented here indicate that the bioavailability of prions in soil for the environmental transmission of scrapie or BSE may be influenced by the temperature of the soil. However, it remains to be seen whether the reported influence of temperature on prion interaction with a sandy-loam soil is consistent with other soil types. Of course, it should also be considered that temperature would be just one of a range of factors influencing the bioavailability of prions from soil; other factors would likely include soil type, prion strain and the biological matrix of the prion source. Scrapie and CWD are known to be spread by environmental routes and therefore understanding the range of factors that influence the persistence of environmental prions is vital in developing eradication programmes.

Keywords: BSE, environment, prion, scrapie, soil, transmission


Using in vitro Prion replication for high sensitive detection of prions and prionlike proteins and for understanding mechanisms of transmission. 

Claudio Soto Mitchell Center for Alzheimer's diseases and related Brain disorders, Department of Neurology, University of Texas Medical School at Houston. 

Prion and prion-like proteins are misfolded protein aggregates with the ability to selfpropagate to spread disease between cells, organs and in some cases across individuals. I n T r a n s m i s s i b l e s p o n g i f o r m encephalopathies (TSEs), prions are mostly composed by a misfolded form of the prion protein (PrPSc), which propagates by transmitting its misfolding to the normal prion protein (PrPC). The availability of a procedure to replicate prions in the laboratory may be important to study the mechanism of prion and prion-like spreading and to develop high sensitive detection of small quantities of misfolded proteins in biological fluids, tissues and environmental samples. Protein Misfolding Cyclic Amplification (PMCA) is a simple, fast and efficient methodology to mimic prion replication in the test tube. PMCA is a platform technology that may enable amplification of any prion-like misfolded protein aggregating through a seeding/nucleation process. In TSEs, PMCA is able to detect the equivalent of one single molecule of infectious PrPSc and propagate prions that maintain high infectivity, strain properties and species specificity. Using PMCA we have been able to detect PrPSc in blood and urine of experimentally infected animals and humans affected by vCJD with high sensitivity and specificity. Recently, we have expanded the principles of PMCA to amplify amyloid-beta (Aβ) and alphasynuclein (α-syn) aggregates implicated in Alzheimer's and Parkinson's diseases, respectively. Experiments are ongoing to study the utility of this technology to detect Aβ and α-syn aggregates in samples of CSF and blood from patients affected by these diseases.

=========================

***>>> Recently, we have been using PMCA to study the role of environmental prion contamination on the horizontal spreading of TSEs. These experiments have focused on the study of the interaction of prions with plants and environmentally relevant surfaces. Our results show that plants (both leaves and roots) bind tightly to prions present in brain extracts and excreta (urine and feces) and retain even small quantities of PrPSc for long periods of time. Strikingly, ingestion of prioncontaminated leaves and roots produced disease with a 100% attack rate and an incubation period not substantially longer than feeding animals directly with scrapie brain homogenate. Furthermore, plants can uptake prions from contaminated soil and transport them to different parts of the plant tissue (stem and leaves). Similarly, prions bind tightly to a variety of environmentally relevant surfaces, including stones, wood, metals, plastic, glass, cement, etc. Prion contaminated surfaces efficiently transmit prion disease when these materials were directly injected into the brain of animals and strikingly when the contaminated surfaces were just placed in the animal cage. These findings demonstrate that environmental materials can efficiently bind infectious prions and act as carriers of infectivity, suggesting that they may play an important role in the horizontal transmission of the disease.

========================

Since its invention 13 years ago, PMCA has helped to answer fundamental questions of prion propagation and has broad applications in research areas including the food industry, blood bank safety and human and veterinary disease diagnosis. 

source reference Prion Conference 2015 abstract book

Grass Plants Bind, Retain, Uptake, and Transport Infectious Prions

Sandra Pritzkow,1 Rodrigo Morales,1 Fabio Moda,1,3 Uffaf Khan,1 Glenn C. Telling,2 Edward Hoover,2 and Claudio Soto1, * 1Mitchell Center for Alzheimer’s Disease and Related Brain Disorders, Department of Neurology, University of Texas Medical School at Houston, 6431 Fannin Street, Houston, TX 77030, USA

2Prion Research Center, Department of Microbiology, Immunology, and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO 80523, USA

3Present address: IRCCS Foundation Carlo Besta Neurological Institute, 20133 Milan, Italy *Correspondence: claudio.soto@uth.tmc.edu http://dx.doi.org/10.1016/j.celrep.2015.04.036

SUMMARY

Prions are the protein-based infectious agents responsible for prion diseases. Environmental prion contamination has been implicated in disease transmission. Here, we analyzed the binding and retention of infectious prion protein (PrPSc) to plants. Small quantities of PrPSc contained in diluted brain homogenate or in excretory materials (urine and feces) can bind to wheat grass roots and leaves. Wild-type hamsters were efficiently infected by ingestion of prion-contaminated plants. The prion-plant interaction occurs with prions from diverse origins, including chronic wasting disease. Furthermore, leaves contaminated by spraying with a prion-containing preparation retained PrPSc for several weeks in the living plant. Finally, plants can uptake prions from contaminated soil and transport them to aerial parts of the plant (stem and leaves). These findings demonstrate that plants can efficiently bind infectious prions and act as carriers of infectivity, suggesting a possible role of environmental prion contamination in the horizontal transmission of the disease.

INTRODUCTION

snip...

DISCUSSION

This study shows that plants can efficiently bind prions contained in brain extracts from diverse prion infected animals, including CWD-affected cervids. PrPSc attached to leaves and roots from wheat grass plants remains capable of seeding prion replication in vitro. Surprisingly, the small quantity of PrPSc naturally excreted in urine and feces from sick hamster or cervids was enough to efficiently contaminate plant tissue. Indeed, our results suggest that the majority of excreted PrPSc is efficiently captured by plants’ leaves and roots. Moreover, leaves can be contaminated by spraying them with a prion-containing extract, and PrPSc remains detectable in living plants for as long as the study was performed (several weeks). Remarkably, prion contaminated plants transmit prion disease to animals upon ingestion, producing a 100% attack rate and incubation periods not substantially longer than direct oral administration of sick brain homogenates.

Finally, an unexpected but exciting result was that plants were able to uptake prions from contaminated soil and transport them to aerial parts of the plant tissue. Although it may seem farfetched that plants can uptake proteins from the soil and transport it to the parts above the ground, there are already published reports of this phenomenon (McLaren et al., 1960; Jensen and McLaren, 1960;Paungfoo-Lonhienne et al., 2008). The high resistance of prions to degradation and their ability to efficiently cross biological barriers may play a role in this process. The mechanism by which plants bind, retain, uptake, and transport prions is unknown. We are currently studying the way in which prions interact with plants using purified, radioactively labeled PrPSc to determine specificity of the interaction, association constant, reversibility, saturation, movement, etc.

Epidemiological studies have shown numerous instances of scrapie or CWD recurrence upon reintroduction of animals on pastures previously exposed to prion-infected animals. Indeed, reappearance of scrapie has been documented following fallow periods of up to 16 years (Georgsson et al., 2006), and pastures were shown to retain infectious CWD prions for at least 2 years after exposure (Miller et al., 2004). It is likely that the environmentally mediated transmission of prion diseases depends upon the interaction of prions with diverse elements, including soil, water, environmental surfaces, various invertebrate animals, and plants.

However, since plants are such an important component of the environment and also a major source of food for many animal species, including humans, our results may have far-reaching implications for animal and human health. Currently, the perception of the riskfor animal-to-human prion transmission has beenmostly limited to consumption or exposure to contaminated meat; our results indicate that plants might also be an important vector of transmission that needs to be considered in risk assessment. 

https://www.cell.com/cell-reports/pdf/S2211-1247%2815%2900437-4.pdf

Published: 07 October 2021

Review on PRNP genetics and susceptibility to chronic wasting disease of Cervidae

Katayoun Moazami-Goudarzi, Olivier Andréoletti, Jean-Luc Vilotte & Vincent Béringue 

Veterinary Research volume 52, Article number: 128 (2021) Cite this article

Abstract

To date, chronic wasting disease (CWD) is the most infectious form of prion disease affecting several captive, free ranging and wild cervid species. Responsible for marked population declines in North America, its geographical spread is now becoming a major concern in Europe. Polymorphisms in the prion protein gene (PRNP) are an important factor influencing the susceptibility to prions and their rate of propagation. All reported cervid PRNP genotypes are affected by CWD. However, in each species, some polymorphisms are associated with lower attack rates and slower progression of the disease. This has potential consequences in terms of genetic selection, CWD diffusion and strain evolution. CWD also presents a zoonotic risk due to prions capacity to cross species barriers. This review summarizes our current understanding of CWD control, focusing on PRNP genetic, strain diversity and capacity to infect other animal species, including humans.

snip...

CWD positive animals with extended time before they succumb to disease likely represent a source of chronic prion shedding within populations and may contribute to environmental contamination. 


***> CWD positive animals with extended time before they succumb to disease likely represent a source of chronic prion shedding within populations and may contribute to environmental contamination. <***

Genes (Basel) . 2021 Sep 10;12(9):1396. doi: 10.3390/genes12091396.

Selective Breeding for Disease-Resistant PRNP Variants to Manage Chronic Wasting Disease in Farmed Whitetail Deer

Nicholas Haley 1, Rozalyn Donner 1, Kahla Merrett 1, Matthew Miller 1, Kristen Senior 1

Affiliations expand

PMID: 34573378 DOI: 10.3390/genes12091396

Abstract

Chronic wasting disease (CWD) is a fatal transmissible spongiform encephalopathy (TSE) of cervids caused by a misfolded variant of the normal cellular prion protein, and it is closely related to sheep scrapie. Variations in a host's prion gene, PRNP, and its primary protein structure dramatically affect susceptibility to specific prion disorders, and breeding for PRNP variants that prevent scrapie infection has led to steep declines in the disease in North American and European sheep. 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. In CWD-endemic areas, depopulation of private herds becomes challenging to justify, leading to opportunities to manage the disease in situ. We developed a selective breeding program for farmed white-tailed deer in a high-prevalence CWD-endemic area which focused on reducing frequencies of highly susceptible PRNP variants and introducing animals with less susceptible variants. With the use of newly developed primers, we found that breeding followed predictable Mendelian inheritance, and early data support our project's utility in reducing CWD prevalence. This project represents a novel approach to CWD management, with future efforts building on these findings.

Keywords: CWD; PRNP; deer; prion; resistance; selective breeding; susceptibility.


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

In Moore et al., reindeer carrying allele E had longer survival-times following intracranial exposure [24]. In the same experiment, a reindeer with a genotype carrier of E, found dead without showing clinical signs ~13 months post-intracranial inoculation, had no histopathological lesions or PrPSc deposition at post-mortem examination.

snip...

Our data support the notion that PRNP genetic variation modulates CWD susceptibility rather than conferring complete resistance. This is in agreement with experimental observations of reindeer-developing CWD after intracranial inoculation regardless of PRNP genotype [24].


***> Our data support the notion that PRNP genetic variation modulates CWD susceptibility rather than conferring complete resistance. 

 Published: 27 May 2021

White-tailed deer S96 prion protein does not support stable in vitro propagation of most common CWD strains

Alicia Otero, Camilo Duque Velásquez, Judd Aiken & Debbie McKenzie 

Scientific Reports volume 11, Article number: 11193 (2021) Cite this article

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Abstract

PrPC variation at residue 96 (G/S) plays an important role in the epidemiology of chronic wasting disease (CWD) in exposed white-tailed deer populations. In vivo studies have demonstrated the protective effect of serine at codon 96, which hinders the propagation of common CWD strains when expressed in homozygosis and increases the survival period of S96/wt heterozygous deer after challenge with CWD. Previous in vitro studies of the transmission barrier suggested that following a single amplification step, wt and S96 PrPC were equally susceptible to misfolding when seeded with various CWD prions. When we performed serial prion amplification in vitro using S96-PrPC, we observed a reduction in the efficiency of propagation with the Wisc-1 or CWD2 strains, suggesting these strains cannot stably template their conformations on this PrPC once the primary sequence has changed after the first round of replication. Our data shows the S96-PrPC polymorphism is detrimental to prion conversion of some CWD strains. These data suggests that deer homozygous for S96-PrPC may not sustain prion transmission as compared to a deer expressing G96-PrPC.

snip...

The protective effect of S96 and H95 alleles was further demonstrated by experimental oral infection in white-tailed deer expressing these amino acid substitutions19. Among the alleles of the PRNP gene associated with a lower CWD incidence and extended preclinical phase, S96 has the highest allelic frequency (~ 25%) after the wt allele in several white-tailed deer populations from the United States and Canada26,27,31. Subsequent independent transmission and epidemiological studies have demonstrated that deer homozygous and heterozygous for S96-PrPC are, compared to wt/wt deer, less susceptible to CWD infection, present prolonged survival times, show delayed prion accumulation and are generally at a significantly earlier stage of disease when deer herds are depopulated23,31,32,33.


***> Subsequent independent transmission and epidemiological studies have demonstrated that deer homozygous and heterozygous for S96-PrPC are, compared to wt/wt deer, less susceptible to CWD infection, present prolonged survival times,

Prion protein polymorphisms associated with reduced CWD susceptibility limit peripheral PrPCWD deposition in orally infected white-tailed deer

Alicia Otero1 , Camilo Duque Velásquez4,5, Chad Johnson3 , Allen Herbst2,5, Rosa Bolea1 , Juan José Badiola1 , Judd Aiken2,5 and Debbie McKenzie4,5*

Abstract

Background: Chronic wasting disease (CWD) is a prion disease affecting members of the Cervidae family. PrPC primary structures play a key role in CWD susceptibility resulting in extended incubation periods and regulating the propagation of CWD strains. We analyzed the distribution of abnormal prion protein (PrPCWD) aggregates in brain and peripheral organs from orally inoculated white-tailed deer expressing four different PRNP genotypes: Q95G96/ Q95G96 (wt/wt), S96/wt, H95/wt and H95/S96 to determine if there are substantial differences in the deposition pattern of PrPCWD between different PRNP genotypes.

Results: Although we detected differences in certain brain areas, globally, the different genotypes showed similar PrPCWD deposition patterns in the brain. However, we found that clinically affected deer expressing H95 PrPC , despite having the longest survival periods, presented less PrPCWD immunoreactivity in particular peripheral organs. In addition, no PrPCWD was detected in skeletal muscle of any of the deer.

Conclusions: Our data suggest that expression of H95-PrPC limits peripheral accumulation of PrPCWD as detected by immunohistochemistry. Conversely, infected S96/wt and wt/wt deer presented with similar PrPCWD peripheral distribution at terminal stage of disease, suggesting that the S96-PrPC allele, although delaying CWD progression, does not completely limit the peripheral accumulation of the infectious agent.

snip...

The significantly longer incubation periods observed in deer with H95-PRNP alleles may not impact secretion of CWD (i.e., less CWD secreted over longer time periods). The emergence of new CWD strains could implicate a zoonotic potential [20]. 

Keywords: Prions, Prion diseases, Chronic wasting disease, CWD, PrPCWD, Peripheral tissues, Polymorphisms, Deer


***> Selective Breeding

***> less susceptible to CWD infection, present prolonged survival times...

this is very disturbing. with all the hype about selective breeding with different alleles, and presenting longer survival times with cwd, this would only allow the spreading of the cwd tse prion to last longer in the given environment imo., and as such has been stated in scientific literature...terry


With cervids, however, resistance based on the PRNP allele alone is not absolute, and is better characterized as a delayed progression [18,25]


Volume 23, Number 9—September 2017 Research Letter

Chronic Wasting Disease Prion Strain Emergence and Host Range Expansion

Allen Herbst1, Camilo Duque Velásquez1, Elizabeth Triscott, Judd M. Aiken, and Debbie McKenzieComments to Author Author affiliations: University of Alberta, Edmonton, Alberta, Canada

Abstract

Human and mouse prion proteins share a structural motif that regulates resistance to common chronic wasting disease (CWD) prion strains. Successful transmission of an emergent strain of CWD prion, H95+, into mice resulted in infection. Thus, emergent CWD prion strains may have higher zoonotic potential than common strains.


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 Department of Microbiology and Immunology, Midwestern University, United States; 2Department of Diagnostic Medicine and Pathobiology, Kansas State University; 3Prion Research Center; Colorado State University; 4U.S. Geological Survey, Pennsylvania Cooperative Fish and Wildlife Research Unit; 5Agricultural Research Service, United States Department of Agriculture; 6Canadian Food Inspection Agency, National and OlE Reference Laboratory for Scrapie and CWD

In mammalian species, the susceptibility to prion diseases is affected, in part, by the sequence of the host's prion protein (PrP). In sheep, a gradation from scrapie susceptible to resistant has been established both in vivo and in vitro based on the amino acids present at PrP positions 136, 154, and 171, which has led to global breeding programs to reduce the prevalence of scrapie in domestic sheep. In cervids, resistance is commonly characterized as a delayed progression of chronic wasting disease (CWD); at present, no cervid PrP allele conferring absolute resistance to prion infection has been identified. To model the susceptibility of various naturally-occurring and hypothetical cervid PrP alleles in vitro, we compared the amplification rates and efficiency of various CWD isolates in recombinant PrPC using real time quaking-induced conversion. We hypothesized that amplification metrics of these isolates in cervid PrP substrates would correlate to in vivo susceptibility - allowing susceptibility prediction for alleles found at 10 frequency in nature, and that there would be an additive effect of multiple resistant codons in hypothetical alleles. 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


''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.


''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.


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.









THURSDAY, DECEMBER 16, 2021 

Detection of CWD prions in naturally infected white‑tailed deer fetuses and gestational tissues by PMCA


THURSDAY, DECEMBER 16, 2021 

RT‑QuIC detection of CWD prion seeding activity in white‑tailed deer muscle tissues


ARS RESEARCH Generation of human chronic wasting disease in transgenic mice 

Publication Acceptance Date: 9/8/2021

Research Project: Pathobiology, Genetics, and Detection of Transmissible Spongiform Encephalopathies Location: Virus and Prion Research

Title: Generation of human chronic wasting disease in transgenic mice

Author item WANG, ZERUI - Case Western Reserve University (CWRU) item QIN, KEFENG - University Of Chicago item CAMACHO, MANUEL - Case Western Reserve University (CWRU) item SHEN, PINGPING - Case Western Reserve University (CWRU) item YUAN, JUE - Case Western Reserve University (CWRU) item Greenlee, Justin item CUI, LI - Jilin University item KONG, QINGZHONG - Case Western Reserve University (CWRU) item MASTRIANNI, JAMES - University Of Chicago item ZOU, WEN-QUAN - Case Western Reserve University (CWRU)

Submitted to: Acta Neuropathologica Publication Type: Peer Reviewed Journal Publication Acceptance Date: 9/8/2021 Publication Date: N/A Citation: N/A

Interpretive Summary: Prion diseases are invariably fatal neurologic diseases for which there is no known prevention or cure. Chronic wasting disease (CWD) is the prion disease of deer and elk and is present in farmed and free ranging herds throughout North America. To date there is no clear evidence that the CWD agent could be transmitted to humans. This manuscript describes the use of an in vitro technique, cell-free serial protein misfolding cyclic amplification (sPMCA), to generate a CWD prion that is infectious to transgenic mice expressing the human prion protein. This study provides the first evidence that CWD prions may be able to cause misfolding in the human prion protein. This information will impact medical experts and those involved in making policy for farmed cervids and wildlife.

Technical Abstract: Chronic wasting disease (CWD) is a cervid spongiform encephalopathy or prion disease caused by the infectious prion or PrPSc, a misfolded conformer of cellular prion protein (PrPC). It has rapidly spread in North America and also has been found in Asia and Europe. In contrast to the zoonotic mad cow disease that is the first animal prion disease found transmissible to humans, the transmissibility of CWD to humans remains uncertain although most previous studies have suggested that humans may not be susceptible to CWD. Here we report the generation of an infectious human PrPSc by seeding CWD PrPSc in normal human brain PrPC through the in vitro cell-free serial protein misfolding cyclic amplification (sPMCA). Western blotting confirms that the sPMCA-induced proteinase K-resistant PrPSc is a human form, evidenced by a PrP-specific antibody that recognizes human but not cervid PrP. Remarkably, two lines of humanized transgenic (Tg) mice expressing human PrP-129Val/Val (VV) or -129Met/Met (MM) polymorphism develop prion disease at 233 ± 6 (mean ± SE) days post-inoculation (dpi) and 552 ± 27 dpi, respectively, upon intracerebral inoculation with the sPMCA-generated PrPSc. The brain of diseased Tg mice reveals the electrophoretic profile of PrPSc similar to sporadic Creutzfeldt-Jakob disease (sCJD) MM1 or VV2 subtype but different neuropathological patterns. We believe that our study provides the first evidence that CWD PrPSc is able to convert human PrPC into PrPSc in vitro and the CWD-derived human PrPSc mimics atypical sCJD subtypes in humanized Tg mice.


''The brain of diseased Tg mice reveals the electrophoretic profile of PrPSc similar to sporadic Creutzfeldt-Jakob disease (sCJD) MM1 or VV2 subtype but different neuropathological patterns.'' 

''We believe that our study provides the first evidence that CWD PrPSc is able to convert human PrPC into PrPSc in vitro and the CWD-derived human PrPSc mimics atypical sCJD subtypes in humanized Tg mice.''

Published: 26 September 2021

Generation of human chronic wasting disease in transgenic mice

Zerui Wang, Kefeng Qin, Manuel V. Camacho, Ignazio Cali, Jue Yuan, Pingping Shen, Justin Greenlee, Qingzhong Kong, James A. Mastrianni & Wen-Quan Zou

Acta Neuropathologica Communications volume 9, Article number: 158 (2021)

Abstract

Chronic wasting disease (CWD) is a cervid prion disease caused by the accumulation of an infectious misfolded conformer (PrPSc) of cellular prion protein (PrPC). It has been spreading rapidly in North America and also found in Asia and Europe. Although bovine spongiform encephalopathy (i.e. mad cow disease) is the only animal prion disease known to be zoonotic, the transmissibility of CWD to humans remains uncertain. Here we report the generation of the first CWD-derived infectious human PrPSc by elk CWD PrPSc-seeded conversion of PrPC in normal human brain homogenates using in vitro protein misfolding cyclic amplification (PMCA). Western blotting with human PrP selective antibody confirmed that the PMCA-generated protease-resistant PrPSc was derived from the human PrPC substrate. Two lines of humanized transgenic mice expressing human PrP with either Val or Met at the polymorphic codon 129 developed clinical prion disease following intracerebral inoculation with the PMCA-generated CWD-derived human PrPSc. Diseased mice exhibited distinct PrPSc patterns and neuropathological changes in the brain. Our study, using PMCA and animal bioassays, provides the first evidence that CWD PrPSc can cross the species barrier to convert human PrPC into infectious PrPSc that can produce bona fide prion disease when inoculated into humanized transgenic mice.

Snip...

It is worth noting that the annual number of sporadic CJD (sCJD) cases in the USA has increased, with the total number of suspected and confirmed sCJD cases rising from 284 in 2003 to 511 in 2017 (https://www.cdc.gov/prions/cjd/occurrence-transmission.html). The greatly enhanced CJD surveillance and an aging population in the USA certainly contributed to the observed increase in annual sCJD case numbers in recent years, but the possibility cannot be excluded that some of the increased sCJD prevalence is linked to CWD exposure.

In the present study, using serial protein misfolding cyclic amplification (sPMCA) assay we generate PrPSc by seeding CWD prions in normal human brain homogenates. Importantly, we reveal that two lines of humanized Tg mice expressing human PrP-129VV and 129MM develop prion diseases upon intracerebral inoculation of the abnormal PrP generated by sPMCA. We believe that our study provides the first opportunity to dissect the clinical, pathological and biochemical features of the CWD-derived human prion disease in two lines of humanized Tg mice expressing two major human PrP genotypes, respectively.


i thought i might share some news about cwd zoonosis that i got, that i cannot share or post to the public yet, i promised for various reasons, one that it will cause a shit storm for sure, but it was something i really already knew from previous studies, but, i was told that ;

==================

''As you can imagine, 2 and 5 (especially 5) may raise alarms.  The evidence we have for 4 are not as strong or tight as I would like to have.   At this point, please do not post any of the points publicly yet, but you can refer to points 1-3 in private discussions and all 5 points when discussing with relevant public officials to highlight the long-term risks of CWD zoonosis.''

====================

so, i figure your as about as official as it gets, and i think this science is extremely important for you to know and to converse about with your officials. it's about to burn a whole in my pocket. this is about as close as it will ever get for cwd zoonosis to be proven in my time, this and what Canada Czub et al found with the Macaques, plus an old study from cjd surveillance unit back that showed cjd and a 9% increase in risk from folks that eat venison, i will post all this below for your files Sir. i remember back in the BSE nvCJD days, from when the first BSE case in bovine was confirmed around 1984 maybe 83, i forget the good vets named that screwed it up first, Carol something, but from 83ish to 95 96 when nvCJD was linked to humans from BSE in cattle, so that took 10 to 15 years. hell, at that rate, especially with Texas and cwd zoonsis, hell, i'll be dead before it's official, if ever, so here ya go Sir. there was a grant study on cwd zoonosis that had been going on for some time, i followed it over the years, then the grant date for said study had expired, so, i thought i would write the good Professor about said study i.e. Professor Kong, CWRU et al. i will post the grant study abstract first, and then after that, what reply i got back, about said study that i was told not to post/publish...

CWD ZOONOSIS GRANT FIRST;

===============

Cervid to human prion transmission

Kong, Qingzhong 

Case Western Reserve University, Cleveland, OH, United States

 Abstract Prion disease is transmissible and invariably fatal. Chronic wasting disease (CWD) is the prion disease affecting deer, elk and moose, and it is a widespread and expanding epidemic affecting 22 US States and 2 Canadian provinces so far. CWD poses the most serious zoonotic prion transmission risks in North America because of huge venison consumption (>6 million deer/elk hunted and consumed annually in the USA alone), significant prion infectivity in muscles and other tissues/fluids from CWD-affected cervids, and usually high levels of individual exposure to CWD resulting from consumption of the affected animal among often just family and friends. However, we still do not know whether CWD prions can infect humans in the brain or peripheral tissues or whether clinical/asymptomatic CWD zoonosis has already occurred, and we have no essays to reliably detect CWD infection in humans. We hypothesize that: (1) The classic CWD prion strain can infect humans at low levels in the brain and peripheral lymphoid tissues; (2) The cervid-to-human transmission barrier is dependent on the cervid prion strain and influenced by the host (human) prion protein (PrP) primary sequence; (3) Reliable essays can be established to detect CWD infection in humans; and (4) CWD transmission to humans has already occurred. We will test these hypotheses in 4 Aims using transgenic (Tg) mouse models and complementary in vitro approaches. 

Aim 1 will prove that the classical CWD strain may infect humans in brain or peripheral lymphoid tissues at low levels by conducting systemic bioassays in a set of humanized Tg mouse lines expressing common human PrP variants using a number of CWD isolates at varying doses and routes. Experimental human CWD samples will also be generated for Aim 3. 

Aim 2 will test the hypothesis that the cervid-to-human prion transmission barrier is dependent on prion strain and influenced by the host (human) PrP sequence by examining and comparing the transmission efficiency and phenotypes of several atypical/unusual CWD isolates/strains as well as a few prion strains from other species that have adapted to cervid PrP sequence, utilizing the same panel of humanized Tg mouse lines as in Aim 1. 

Aim 3 will establish reliable essays for detection and surveillance of CWD infection in humans by examining in details the clinical, pathological, biochemical and in vitro seeding properties of existing and future experimental human CWD samples generated from Aims 1-2 and compare them with those of common sporadic human Creutzfeldt-Jakob disease (sCJD) prions. 

Aim 4 will attempt to detect clinical CWD-affected human cases by examining a significant number of brain samples from prion-affected human subjects in the USA and Canada who have consumed venison from CWD-endemic areas utilizing the criteria and essays established in Aim 3. The findings from this proposal will greatly advance our understandings on the potential and characteristics of cervid prion transmission in humans, establish reliable essays for CWD zoonosis and potentially discover the first case(s) of CWD infection in humans.

Public Health Relevance There are significant and increasing human exposure to cervid prions because chronic wasting disease (CWD, a widespread and highly infectious prion disease among deer and elk in North America) continues spreading and consumption of venison remains popular, but our understanding on cervid-to-human prion transmission is still very limited, raising public health concerns. This proposal aims to define the zoonotic risks of cervid prions and set up and apply essays to detect CWD zoonosis using mouse models and in vitro methods. The findings will greatly expand our knowledge on the potentials and characteristics of cervid prion transmission in humans, establish reliable essays for such infections and may discover the first case(s) of CWD infection in humans.

 Funding Agency Agency National Institute of Health (NIH) Institute National Institute of Neurological Disorders and Stroke (NINDS) Type Research Project (R01) Project # 1R01NS088604-01A1 Application # 9037884 Study Section Cellular and Molecular Biology of Neurodegeneration Study Section (CMND) Program Officer Wong, May Project Start 2015-09-30 Project End 2019-07-31 Budget Start 2015-09-30 Budget End 2016-07-31 Support Year 1 Fiscal Year 2015 Total Cost $337,507 Indirect Cost $118,756

snip... 


Professor Kongs reply to me just this month about above grant study that has NOT been published in peer reveiw yet...

=================================

Here is a brief summary of our findings:

snip...can't post, made a promise...tss

On Sat, Apr 3, 2021 at 12:19 PM Terry Singeltary <flounder9@verizon.net> wrote:

snip...

end...tss

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CWD ZOONOSIS THE FULL MONTY TO DATE

International Conference on Emerging Diseases, Outbreaks & Case Studies & 16th Annual Meeting on Influenza March 28-29, 2018 | Orlando, USA

Qingzhong Kong

Case Western Reserve University School of Medicine, USA

Zoonotic potential of chronic wasting disease prions from cervids

Chronic wasting disease (CWD) is the prion disease in cervids (mule deer, white-tailed deer, American elk, moose, and reindeer). It has become an epidemic in North America, and it has been detected in the Europe (Norway) since 2016. The widespread CWD and popular hunting and consumption of cervid meat and other products raise serious public health concerns, but questions remain on human susceptibility to CWD prions, especially on the potential difference in zoonotic potential among the various CWD prion strains. We have been working to address this critical question for well over a decade. We used CWD samples from various cervid species to inoculate transgenic mice expressing human or elk prion protein (PrP). We found infectious prions in the spleen or brain in a small fraction of CWD-inoculated transgenic mice expressing human PrP, indicating that humans are not completely resistant to CWD prions; this finding has significant ramifications on the public health impact of CWD prions. The influence of cervid PrP polymorphisms, the prion strain dependence of CWD-to-human transmission barrier, and the characterization of experimental human CWD prions will be discussed.

Speaker Biography Qingzhong Kong has completed his PhD from the University of Massachusetts at Amherst and Post-doctoral studies at Yale University. He is currently an Associate Professor of Pathology, Neurology and Regenerative Medicine. He has published over 50 original research papers in reputable journals (including Science Translational Medicine, JCI, PNAS and Cell Reports) and has been serving as an Editorial Board Member on seven scientific journals. He has multiple research interests, including public health risks of animal prions (CWD of cervids and atypical BSE of cattle), animal modeling of human prion diseases, mechanisms of prion replication and pathogenesis, etiology of sporadic Creutzfeldt-Jacob disease (CJD) in humans, normal cellular PrP in the biology and pathology of multiple brain and peripheral diseases, proteins responsible for the α-cleavage of cellular PrP, as well as gene therapy and DNA vaccination.






SUNDAY, JULY 25, 2021 

North American and Norwegian Chronic Wasting Disease prions exhibit different potential for interspecies transmission and zoonotic risk 

''Our data suggest that reindeer and red deer from Norway could be the most transmissible CWD prions to other mammals, whereas North American CWD prions were more prone to generate human prions in vitro.''


MONDAY, JULY 19, 2021 

***> U Calgary researchers at work on a vaccine against a fatal infectious disease affecting deer and potentially people


Prion Conference 2018 Abstracts

BSE aka MAD COW DISEASE, was first discovered in 1984, and it took until 1995 to finally admit that BSE was causing nvCJD, the rest there is history, but that science is still evolving i.e. science now shows that indeed atypical L-type BSE, atypical Nor-98 Scrapie, and typical Scrapie are all zoonosis, zoonotic for humans, there from. 

HOW long are we going to wait for Chronic Wasting Disease, CWD TSE Prion of Cervid, and zoonosis, zoonotic tranmission to humans there from?

Studies have shown since 1994 that humans are susceptible to CWD TSE Prion, so, what's the hold up with making CWD a zoonotic zoonosis disease, the iatrogenic transmissions there from is not waiting for someone to make a decision.

Prion Conference 2018 Abstracts

P190 Human prion disease mortality rates by occurrence of chronic wasting disease in freeranging cervids, United States

Abrams JY (1), Maddox RA (1), Schonberger LB (1), Person MK (1), Appleby BS (2), Belay ED (1)

(1) Centers for Disease Control and Prevention (CDC), National Center for Emerging and Zoonotic Infectious Diseases, Atlanta, GA, USA (2) Case Western Reserve University, National Prion Disease Pathology Surveillance Center (NPDPSC), Cleveland, OH, USA.

Background

Chronic wasting disease (CWD) is a prion disease of deer and elk that has been identified in freeranging cervids in 23 US states. While there is currently no epidemiological evidence for zoonotic transmission through the consumption of contaminated venison, studies suggest the CWD agent can cross the species barrier in experimental models designed to closely mimic humans. We compared rates of human prion disease in states with and without CWD to examine the possibility of undetermined zoonotic transmission.

Methods

Death records from the National Center for Health Statistics, case records from the National Prion Disease Pathology Surveillance Center, and additional state case reports were combined to create a database of human prion disease cases from 2003-2015. Identification of CWD in each state was determined through reports of positive CWD tests by state wildlife agencies. Age- and race-adjusted mortality rates for human prion disease, excluding cases with known etiology, were determined for four categories of states based on CWD occurrence: highly endemic (>16 counties with CWD identified in free-ranging cervids); moderately endemic (3-10 counties with CWD); low endemic (1-2 counties with CWD); and no CWD states. States were counted as having no CWD until the year CWD was first identified. Analyses stratified by age, sex, and time period were also conducted to focus on subgroups for which zoonotic transmission would be more likely to be detected: cases <55 years old, male sex, and the latter half of the study (2010-2015).

Results

Highly endemic states had a higher rate of prion disease mortality compared to non-CWD states (rate ratio [RR]: 1.12, 95% confidence interval [CI] = 1.01 - 1.23), as did low endemic states (RR: 1.15, 95% CI = 1.04 - 1.27). Moderately endemic states did not have an elevated mortality rate (RR: 1.05, 95% CI = 0.93 - 1.17). In age-stratified analyses, prion disease mortality rates among the <55 year old population were elevated for moderately endemic states (RR: 1.57, 95% CI = 1.10 – 2.24) while mortality rates were elevated among those ≥55 for highly endemic states (RR: 1.13, 95% CI = 1.02 - 1.26) and low endemic states (RR: 1.16, 95% CI = 1.04 - 1.29). In other stratified analyses, prion disease mortality rates for males were only elevated for low endemic states (RR: 1.27, 95% CI = 1.10 - 1.48), and none of the categories of CWD-endemic states had elevated mortality rates for the latter time period (2010-2015).

Conclusions

While higher prion disease mortality rates in certain categories of states with CWD in free-ranging cervids were noted, additional stratified analyses did not reveal markedly elevated rates for potentially sensitive subgroups that would be suggestive of zoonotic transmission. Unknown confounding factors or other biases may explain state-by-state differences in prion disease mortality.

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P172 Peripheral Neuropathy in Patients with Prion Disease

Wang H(1), Cohen M(1), Appleby BS(1,2)

(1) University Hospitals Cleveland Medical Center, Cleveland, Ohio (2) National Prion Disease Pathology Surveillance Center, Cleveland, Ohio.

Prion disease is a fatal progressive neurodegenerative disease due to deposition of an abnormal protease-resistant isoform of prion protein. Typical symptoms include rapidly progressive dementia, myoclonus, visual disturbance and hallucinations. Interestingly, in patients with prion disease, the abnormal protein canould also be found in the peripheral nervous system. Case reports of prion deposition in peripheral nerves have been reported. Peripheral nerve involvement is thought to be uncommon; however, little is known about the exact prevalence and features of peripheral neuropathy in patients with prion disease.

We reviewed autopsy-proven prion cases from the National Prion Disease Pathology Surveillance Center that were diagnosed between September 2016 to March 2017. We collected information regarding prion protein diagnosis, demographics, comorbidities, clinical symptoms, physical exam, neuropathology, molecular subtype, genetics lab, brain MRI, image and EMG reports. Our study included 104 patients. Thirteen (12.5%) patients had either subjective symptoms or objective signs of peripheral neuropathy. Among these 13 patients, 3 had other known potential etiologies of peripheral neuropathy such as vitamin B12 deficiency or prior chemotherapy. Among 10 patients that had no other clear etiology, 3 (30%) had familial CJD. The most common sCJD subtype was MV1-2 (30%), followed by MM1-2 (20%). The Majority of cases wasere male (60%). Half of them had exposure to wild game. The most common subjective symptoms were tingling and/or numbness of distal extremities. The most common objective finding was diminished vibratory sensation in the feet. Half of them had an EMG with the findings ranging from fasciculations to axonal polyneuropathy or demyelinating polyneuropathy.

Our study provides an overview of the pattern of peripheral neuropathy in patients with prion disease. Among patients with peripheral neuropathy symptoms or signs, majority has polyneuropathy. It is important to document the baseline frequency of peripheral neuropathy in prion diseases as these symptoms may become important when conducting surveillance for potential novel zoonotic prion diseases.

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P177 PrP plaques in methionine homozygous Creutzfeldt-Jakob disease patients as a potential marker of iatrogenic transmission

Abrams JY (1), Schonberger LB (1), Cali I (2), Cohen Y (2), Blevins JE (2), Maddox RA (1), Belay ED (1), Appleby BS (2), Cohen ML (2)

(1) Centers for Disease Control and Prevention (CDC), National Center for Emerging and Zoonotic Infectious Diseases, Atlanta, GA, USA (2) Case Western Reserve University, National Prion Disease Pathology Surveillance Center (NPDPSC), Cleveland, OH, USA.

Background

Sporadic Creutzfeldt-Jakob disease (CJD) is widely believed to originate from de novo spontaneous conversion of normal prion protein (PrP) to its pathogenic form, but concern remains that some reported sporadic CJD cases may actually be caused by disease transmission via iatrogenic processes. For cases with methionine homozygosity (CJD-MM) at codon 129 of the PRNP gene, recent research has pointed to plaque-like PrP deposition as a potential marker of iatrogenic transmission for a subset of cases. This phenotype is theorized to originate from specific iatrogenic source CJD types that comprise roughly a quarter of known CJD cases.

Methods

We reviewed scientific literature for studies which described PrP plaques among CJD patients with known epidemiological links to iatrogenic transmission (receipt of cadaveric human grown hormone or dura mater), as well as in cases of reported sporadic CJD. The presence and description of plaques, along with CJD classification type and other contextual factors, were used to summarize the current evidence regarding plaques as a potential marker of iatrogenic transmission. In addition, 523 cases of reported sporadic CJD cases in the US from January 2013 through September 2017 were assessed for presence of PrP plaques.

Results

We identified four studies describing 52 total cases of CJD-MM among either dura mater recipients or growth hormone recipients, of which 30 were identified as having PrP plaques. While sporadic cases were not generally described as having plaques, we did identify case reports which described plaques among sporadic MM2 cases as well as case reports of plaques exclusively in white matter among sporadic MM1 cases. Among the 523 reported sporadic CJD cases, 0 of 366 MM1 cases had plaques, 2 of 48 MM2 cases had kuru plaques, and 4 of 109 MM1+2 cases had either kuru plaques or both kuru and florid plaques. Medical chart review of the six reported sporadic CJD cases with plaques did not reveal clinical histories suggestive of potential iatrogenic transmission.

Conclusions

PrP plaques occur much more frequently for iatrogenic CJD-MM cases compared to sporadic CJDMM cases. Plaques may indicate iatrogenic transmission for CJD-MM cases without a type 2 Western blot fragment. The study results suggest the absence of significant misclassifications of iatrogenic CJD as sporadic. To our knowledge, this study is the first to describe grey matter kuru plaques in apparently sporadic CJD-MM patients with a type 2 Western blot fragment.

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P180 Clinico-pathological analysis of human prion diseases in a brain bank series

Ximelis T (1), Aldecoa I (1,2), Molina-Porcel L (1,3), Grau-Rivera O (4), Ferrer I (5), Nos C (6), Gelpi E (1,7), Sánchez-Valle R (1,4)

(1) Neurological Tissue Bank of the Biobanc-Hospital ClÃnic-IDIBAPS, Barcelona, Spain (2) Pathological Service of Hospital ClÃnic de Barcelona, Barcelona, Spain (3) EAIA Trastorns Cognitius, Centre Emili Mira, Parc de Salut Mar, Barcelona, Spain (4) Department of Neurology of Hospital ClÃnic de Barcelona, Barcelona, Spain (5) Institute of Neuropathology, Hospital Universitari de Bellvitge, Hospitalet de Llobregat, Barcelona (6) General subdirectorate of Surveillance and Response to Emergencies in Public Health, Department of Public Health in Catalonia, Barcelona, Spain (7) Institute of Neurology, Medical University of Vienna, Vienna, Austria.

Background and objective:

The Neurological Tissue Bank (NTB) of the Hospital Clínic-Institut d‘Investigacions Biomèdiques August Pi i Sunyer, Barcelona, Spain is the reference center in Catalonia for the neuropathological study of prion diseases in the region since 2001. The aim of this study is to analyse the characteristics of the confirmed prion diseases registered at the NTB during the last 15 years.

Methods:

We reviewed retrospectively all neuropathologically confirmed cases registered during the period January 2001 to December 2016.

Results:

176 cases (54,3% female, mean age: 67,5 years and age range: 25-86 years) of neuropathological confirmed prion diseases have been studied at the NTB. 152 cases corresponded to sporadic Creutzfeldt-Jakob disease (sCJD), 10 to genetic CJD, 10 to Fatal Familial Insomnia, 2 to GerstmannSträussler-Scheinker disease, and 2 cases to variably protease-sensitive prionopathy (VPSPr). Within sCJD subtypes the MM1 subtype was the most frequent, followed by the VV2 histotype.

Clinical and neuropathological diagnoses agreed in 166 cases (94%). The clinical diagnosis was not accurate in 10 patients with definite prion disease: 1 had a clinical diagnosis of Fronto-temporal dementia (FTD), 1 Niemann-Pick‘s disease, 1 Lewy Body‘s Disease, 2 Alzheimer‘s disease, 1 Cortico-basal syndrome and 2 undetermined dementia. Among patients with VPSPr, 1 had a clinical diagnosis of Amyotrophic lateral sclerosis (ALS) and the other one with FTD.

Concomitant pathologies are frequent in older age groups, mainly AD neuropathological changes were observed in these subjects.

Discussion:

A wide spectrum of human prion diseases have been identified in the NTB being the relative frequencies and main characteristics like other published series. There is a high rate of agreement between clinical and neuropathological diagnoses with prion diseases. These findings show the importance that public health has given to prion diseases during the past 15 years. Continuous surveillance of human prion disease allows identification of new emerging phenotypes. Brain tissue samples from these donors are available to the scientific community. For more information please visit:


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P192 Prion amplification techniques for the rapid evaluation of surface decontamination procedures

Bruyere-Ostells L (1), Mayran C (1), Belondrade M (1), Boublik Y (2), Haïk S (3), Fournier-Wirth C (1), Nicot S (1), Bougard D (1)

(1) Pathogenesis and control of chronic infections, Etablissement Français du Sang, Inserm, Université de Montpellier, Montpellier, France. (2) Centre de Recherche en Biologie cellulaire de Montpellier, CNRS, Université de Montpellier, Montpellier, France. (3) Inserm U 1127, CNRS UMR 7225, Sorbonne Universités, UPMC Université Paris 06 UMR S 1127, Institut du Cerveau et de la Moelle épinière, ICM, Paris, France.

Aims:

Transmissible Spongiform Encephalopathies (TSE) or prion diseases are a group of incurable and always fatal neurodegenerative disorders including Creutzfeldt-Jakob diseases (CJD) in humans. These pathologies include sporadic (sCJD), genetic and acquired (variant CJD) forms. By the past, sCJD and vCJD were transmitted by different prion contaminated biological materials to patients resulting in more than 400 iatrogenic cases (iCJD). The atypical nature and the biochemical properties of the infectious agent, formed by abnormal prion protein or PrPTSE, make it particularly resistant to conventional decontamination procedures. In addition, PrPTSE is widely distributed throughout the organism before clinical onset in vCJD and can also be detected in some peripheral tissues in sporadic CJD. Risk of iatrogenic transmission of CJD by contaminated medical device remains thus a concern for healthcare facilities. Bioassay is the gold standard method to evaluate the efficacy of prion decontamination procedures but is time-consuming and expensive. Here, we propose to compare in vitro prion amplification techniques: Protein Misfolding Cyclic Amplification (PMCA) and Real-Time Quaking Induced Conversion (RT-QuIC) for the detection of residual prions on surface after decontamination.

Methods:

Stainless steel wires, by mimicking the surface of surgical instruments, were proposed as a carrier model of prions for inactivation studies. To determine the sensitivity of the two amplification techniques on wires (Surf-PMCA and Surf-QuIC), steel wires were therefore contaminated with serial dilutions of brain homogenates (BH) from a 263k infected hamster and from a patient with sCJD (MM1 subtype). We then compared the different standard decontamination procedures including partially and fully efficient treatments by detecting the residual seeding activity on 263K and sCJD contaminated wires. We completed our study by the evaluation of marketed reagents endorsed for prion decontamination.

Results:

The two amplification techniques can detect minute quantities of PrPTSE adsorbed onto a single wire. 8/8 wires contaminated with a 10-6 dilution of 263k BH and 1/6 with the 10-8 dilution are positive with Surf-PMCA. Similar performances were obtained with Surf-QuIC on 263K: 10/16 wires contaminated with 10-6 dilution and 1/8 wires contaminated with 10-8 dilution are positive. Regarding the human sCJD-MM1 prion, Surf-QuIC allows us to detect 16/16 wires contaminated with 10-6 dilutions and 14/16 with 10-7 . Results obtained after decontamination treatments are very similar between 263K and sCJD prions. Efficiency of marketed treatments to remove prions is lower than expected.

Conclusions:

Surf-PMCA and Surf-QuIC are very sensitive methods for the detection of prions on wires and could be applied to prion decontamination studies for rapid evaluation of new treatments. Sodium hypochlorite is the only product to efficiently remove seeding activity of both 263K and sCJD prions.

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WA2 Oral transmission of CWD into Cynomolgus macaques: signs of atypical disease, prion conversion and infectivity in macaques and bio-assayed transgenic mice

Schatzl HM (1, 2), Hannaoui S (1, 2), Cheng Y-C (1, 2), Gilch S (1, 2), Beekes M (3), SchulzSchaeffer W (4), Stahl-Hennig C (5) and Czub S (2, 6)

(1) University of Calgary, Calgary Prion Research Unit, Calgary, Canada (2) University of Calgary, Faculty of Veterinary Medicine, Calgary, Canada, (3) Robert Koch Institute, Berlin, Germany, (4) University of Homburg/Saar, Homburg, Germany, (5) German Primate Center, Goettingen, Germany, (6) Canadian Food Inspection Agency (CFIA), Lethbridge, Canada.

To date, BSE is the only example of interspecies transmission of an animal prion disease into humans. The potential zoonotic transmission of CWD is an alarming issue and was addressed by many groups using a variety of in vitro and in vivo experimental systems. Evidence from these studies indicated a substantial, if not absolute, species barrier, aligning with the absence of epidemiological evidence suggesting transmission into humans. Studies in non-human primates were not conclusive so far, with oral transmission into new-world monkeys and no transmission into old-world monkeys. Our consortium has challenged 18 Cynomolgus macaques with characterized CWD material, focusing on oral transmission with muscle tissue. Some macaques have orally received a total of 5 kg of muscle material over a period of 2 years. After 5-7 years of incubation time some animals showed clinical symptoms indicative of prion disease, and prion neuropathology and PrPSc deposition were found in spinal cord and brain of euthanized animals. PrPSc in immunoblot was weakly detected in some spinal cord materials and various tissues tested positive in RT-QuIC, including lymph node and spleen homogenates. To prove prion infectivity in the macaque tissues, we have intracerebrally inoculated 2 lines of transgenic mice, expressing either elk or human PrP. At least 3 TgElk mice, receiving tissues from 2 different macaques, showed clinical signs of a progressive prion disease and brains were positive in immunoblot and RT-QuIC. Tissues (brain, spinal cord and spleen) from these and preclinical mice are currently tested using various read-outs and by second passage in mice. Transgenic mice expressing human PrP were so far negative for clear clinical prion disease (some mice >300 days p.i.). In parallel, the same macaque materials are inoculated into bank voles. Taken together, there is strong evidence of transmissibility of CWD orally into macaques and from macaque tissues into transgenic mouse models, although with an incomplete attack rate. The clinical and pathological presentation in macaques was mostly atypical, with a strong emphasis on spinal cord pathology. Our ongoing studies will show whether the transmission of CWD into macaques and passage in transgenic mice represents a form of non-adaptive prion amplification, and whether macaque-adapted prions have the potential to infect mice expressing human PrP. The notion that CWD can be transmitted orally into both new-world and old-world non-human primates asks for a careful reevaluation of the zoonotic risk of CWD.

See also poster P103

***> The notion that CWD can be transmitted orally into both new-world and old-world non-human primates asks for a careful reevaluation of the zoonotic risk of CWD.

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WA16 Monitoring Potential CWD Transmission to Humans

Belay ED

Centers for Disease Control and Prevention (CDC), National Center for Emerging and Zoonotic Infectious Diseases, Atlanta, GA, USA.

The spread of chronic wasting disease (CWD) in animals has raised concerns about increasing human exposure to the CWD agent via hunting and venison consumption, potentially facilitating CWD transmission to humans. Several studies have explored this possibility, including limited epidemiologic studies, in vitro experiments, and laboratory studies using various types of animal models. Most human exposures to the CWD agent in the United States would be expected to occur in association with deer and elk hunting in CWD-endemic areas. The Centers for Disease Control and Prevention (CDC) collaborated with state health departments in Colorado, Wisconsin, and Wyoming to identify persons at risk of CWD exposure and to monitor their vital status over time. Databases were established of persons who hunted in Colorado and Wyoming and those who reported consumption of venison from deer that later tested positive in Wisconsin. Information from the databases is periodically cross-checked with mortality data to determine the vital status and causes of death for deceased persons. Long-term follow-up of these hunters is needed to assess their risk of development of a prion disease linked to CWD exposure.

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P166 Characterization of CJD strain profiles in venison consumers and non-consumers from Alberta and Saskatchewan

Stephanie Booth (1,2), Lise Lamoureux (1), Debra Sorensen (1), Jennifer L. Myskiw (1,2), Megan Klassen (1,2), Michael Coulthart (3), Valerie Sim (4)

(1) Zoonotic Diseases and Special Pathogens, National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg (2) Department of Medical Microbiology and Infectious Diseases, University of Manitoba, Winnipeg (3) Canadian CJD Surveillance System, Public Health Agency of Canada, Ottawa (4) Division of Neurology, Department of Medicine Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton.

Chronic wasting disease (CWD) is spreading rapidly through wild cervid populations in the Canadian provinces of Alberta and Saskatchewan. While this has implications for tourism and hunting, there is also concern over possible zoonotic transmission to humans who eat venison from infected deer. Whilst there is no evidence of any human cases of CWD to date, the Canadian CJD Surveillance System (CJDSS) in Canada is staying vigilant. When variant CJD occurred following exposure to BSE, the unique biochemical fingerprint of the pathologic PrP enabled a causal link to be confirmed. However, we cannot be sure what phenotype human CWD prions would present with, or indeed, whether this would be distinct from that see in sporadic CJD. Therefore we are undertaking a systematic analysis of the molecular diversity of CJD cases of individuals who resided in Alberta and Saskatchewan at their time of death comparing venison consumers and non-consumers, using a variety of clinical, imaging, pathological and biochemical markers. Our initial objective is to develop novel biochemical methodologies that will extend the baseline glycoform and genetic polymorphism typing that is already completed by the CJDSS. Firstly, we are reviewing MRI, EEG and pathology information from over 40 cases of CJD to select clinically affected areas for further investigation. Biochemical analysis will include assessment of the levels of protease sensitive and resistant prion protein, glycoform typing using 2D gel electrophoresis, testing seeding capabilities and kinetics of aggregation by quaking-induced conversion, and determining prion oligomer size distributions with asymmetric flow field fractionation with in-line light scattering. Progress and preliminary data will be presented. Ultimately, we intend to further define the relationship between PrP structure and disease phenotype and establish a baseline for the identification of future atypical CJD cases that may arise as a result of exposure to CWD.

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Source Prion Conference 2018 Abstracts




Volume 24, Number 8—August 2018 Research Susceptibility of Human Prion Protein to Conversion by Chronic Wasting Disease Prions

Marcelo A. BarriaComments to Author , Adriana Libori, Gordon Mitchell, and Mark W. Head Author affiliations: National CJD Research and Surveillance Unit, University of Edinburgh, Edinburgh, Scotland, UK (M.A. Barria, A. Libori, M.W. Head); National and OIE Reference Laboratory for Scrapie and CWD, Canadian Food Inspection Agency, Ottawa, Ontario, Canada (G. Mitchell)

Abstract Chronic wasting disease (CWD) is a contagious and fatal neurodegenerative disease and a serious animal health issue for deer and elk in North America. The identification of the first cases of CWD among free-ranging reindeer and moose in Europe brings back into focus the unresolved issue of whether CWD can be zoonotic like bovine spongiform encephalopathy. We used a cell-free seeded protein misfolding assay to determine whether CWD prions from elk, white-tailed deer, and reindeer in North America can convert the human prion protein to the disease-associated form. We found that prions can convert, but the efficiency of conversion is affected by polymorphic variation in the cervid and human prion protein genes. In view of the similarity of reindeer, elk, and white-tailed deer in North America to reindeer, red deer, and roe deer, respectively, in Europe, a more comprehensive and thorough assessment of the zoonotic potential of CWD might be warranted.

snip...

Discussion Characterization of the transmission properties of CWD and evaluation of their zoonotic potential are important for public health purposes. Given that CWD affects several members of the family Cervidae, it seems reasonable to consider whether the zoonotic potential of CWD prions could be affected by factors such as CWD strain, cervid species, geographic location, and Prnp–PRNP polymorphic variation. We have previously used an in vitro conversion assay (PMCA) to investigate the susceptibility of the human PrP to conversion to its disease-associated form by several animal prion diseases, including CWD (15,16,22). The sensitivity of our molecular model for the detection of zoonotic conversion depends on the combination of 1) the action of proteinase K to degrade the abundant human PrPC that constitutes the substrate while only N terminally truncating any human PrPres produced and 2) the presence of the 3F4 epitope on human but not cervid PrP. In effect, this degree of sensitivity means that any human PrPres formed during the PMCA reaction can be detected down to the limit of Western blot sensitivity. In contrast, if other antibodies that detect both cervid and human PrP are used, such as 6H4, then newly formed human PrPres must be detected as a measurable increase in PrPres over the amount remaining in the reaction product from the cervid seed. Although best known for the efficient amplification of prions in research and diagnostic contexts, the variation of the PMCA method employed in our study is optimized for the definitive detection of zoonotic reaction products of inherently inefficient conversion reactions conducted across species barriers. By using this system, we previously made and reported the novel observation that elk CWD prions could convert human PrPC from human brain and could also convert recombinant human PrPC expressed in transgenic mice and eukaryotic cell cultures (15).

A previous publication suggested that mule deer PrPSc was unable to convert humanized transgenic substrate in PMCA assays (23) and required a further step of in vitro conditioning in deer substrate PMCA before it was able to cross the deer–human molecular barrier (24). However, prions from other species, such as elk (15) and reindeer affected by CWD, appear to be compatible with the human protein in a single round of amplification (as shown in our study). These observations suggest that different deer species affected by CWD could present differing degrees of the olecular compatibility with the normal form of human PrP.

The contribution of the polymorphism at codon 129 of the human PrP gene has been extensively studied and is recognized as a risk factor for Creutzfeldt-Jakob disease (4). In cervids, the equivalent codon corresponds to the position 132 encoding methionine or leucine. This polymorphism in the elk gene has been shown to play an important role in CWD susceptibility (25,26). We have investigated the effect of this cervid Prnp polymorphism on the conversion of the humanized transgenic substrate according to the variation in the equivalent PRNP codon 129 polymorphism. Interestingly, only the homologs methionine homozygous seed–substrate reactions could readily convert the human PrP, whereas the heterozygous elk PrPSc was unable to do so, even though comparable amounts of PrPres were used to seed the reaction. In addition, we observed only low levels of human PrPres formation in the reactions seeded with the homozygous methionine (132 MM) and the heterozygous (132 ML) seeds incubated with the other 2 human polymorphic substrates (129 MV and 129 VV). The presence of the amino acid leucine at position 132 of the elk Prnp gene has been attributed to a lower degree of prion conversion compared with methionine on the basis of experiments in mice made transgenic for these polymorphic variants (26). Considering the differences observed for the amplification of the homozygous human methionine substrate by the 2 polymorphic elk seeds (MM and ML), reappraisal of the susceptibility of human PrPC by the full range of cervid polymorphic variants affected by CWD would be warranted.

In light of the recent identification of the first cases of CWD in Europe in a free-ranging reindeer (R. tarandus) in Norway (2), we also decided to evaluate the in vitro conversion potential of CWD in 2 experimentally infected reindeer (18). Formation of human PrPres was readily detectable after a single round of PMCA, and in all 3 humanized polymorphic substrates (MM, MV, and VV). This finding suggests that CWD prions from reindeer could be more compatible with human PrPC generally and might therefore present a greater risk for zoonosis than, for example, CWD prions from white-tailed deer. A more comprehensive comparison of CWD in the affected species, coupled with the polymorphic variations in the human and deer PRNP–Prnp genes, in vivo and in vitro, will be required before firm conclusions can be drawn. Analysis of the Prnp sequence of the CWD reindeer in Norway was reported to be identical to the specimens used in our study (2). This finding raises the possibility of a direct comparison of zoonotic potential between CWD acquired in the wild and that produced in a controlled laboratory setting. (Table).

The prion hypothesis proposes that direct molecular interaction between PrPSc and PrPC is necessary for conversion and prion replication. Accordingly, polymorphic variants of the PrP of host and agent might play a role in determining compatibility and potential zoonotic risk. In this study, we have examined the capacity of the human PrPC to support in vitro conversion by elk, white-tailed deer, and reindeer CWD PrPSc. Our data confirm that elk CWD prions can convert the human PrPC, at least in vitro, and show that the homologous PRNP polymorphisms at codon 129 and 132 in humans and cervids affect conversion efficiency. Other species affected by CWD, particularly caribou or reindeer, also seem able to convert the human PrP. It will be important to determine whether other polymorphic variants found in other CWD-affected Cervidae or perhaps other factors (17) exert similar effects on the ability to convert human PrP and thus affect their zoonotic potential.

Dr. Barria is a research scientist working at the National CJD Research and Surveillance Unit, University of Edinburgh. His research has focused on understanding the molecular basis of a group of fatal neurologic disorders called prion diseases.

Acknowledgments We thank Aru Balachandran for originally providing cervid brain tissues, Abigail Diack and Jean Manson for providing mouse brain tissue, and James Ironside for his critical reading of the manuscript at an early stage.

This report is independent research commissioned and funded by the United Kingdom’s Department of Health Policy Research Programme and the Government of Scotland. The views expressed in this publication are those of the authors and not necessarily those of the Department of Health or the Government of Scotland.

Author contributions: The study was conceived and designed by M.A.B. and M.W.H. The experiments were conducted by M.A.B. and A.L. Chronic wasting disease brain specimens were provided by G.M. The manuscript was written by M.A.B. and M.W.H. All authors contributed to the editing and revision of the manuscript.



Prion 2017 Conference Abstracts
First evidence of intracranial and peroral transmission of Chronic Wasting Disease (CWD) into Cynomolgus macaques: a work in progress Stefanie Czub1, Walter Schulz-Schaeffer2, Christiane Stahl-Hennig3, Michael Beekes4, Hermann Schaetzl5 and Dirk Motzkus6 1 
University of Calgary Faculty of Veterinary Medicine/Canadian Food Inspection Agency; 2Universitatsklinikum des Saarlandes und Medizinische Fakultat der Universitat des Saarlandes; 3 Deutsches Primaten Zentrum/Goettingen; 4 Robert-Koch-Institut Berlin; 5 University of Calgary Faculty of Veterinary Medicine; 6 presently: Boehringer Ingelheim Veterinary Research Center; previously: Deutsches Primaten Zentrum/Goettingen 
This is a progress report of a project which started in 2009. 
21 cynomolgus macaques were challenged with characterized CWD material from white-tailed deer (WTD) or elk by intracerebral (ic), oral, and skin exposure routes. Additional blood transfusion experiments are supposed to assess the CWD contamination risk of human blood product. Challenge materials originated from symptomatic cervids for ic, skin scarification and partially per oral routes (WTD brain). Challenge material for feeding of muscle derived from preclinical WTD and from preclinical macaques for blood transfusion experiments. We have confirmed that the CWD challenge material contained at least two different CWD agents (brain material) as well as CWD prions in muscle-associated nerves. 
Here we present first data on a group of animals either challenged ic with steel wires or per orally and sacrificed with incubation times ranging from 4.5 to 6.9 years at postmortem. Three animals displayed signs of mild clinical disease, including anxiety, apathy, ataxia and/or tremor. In four animals wasting was observed, two of those had confirmed diabetes. All animals have variable signs of prion neuropathology in spinal cords and brains and by supersensitive IHC, reaction was detected in spinal cord segments of all animals. Protein misfolding cyclic amplification (PMCA), real-time quaking-induced conversion (RT-QuiC) and PET-blot assays to further substantiate these findings are on the way, as well as bioassays in bank voles and transgenic mice. 
At present, a total of 10 animals are sacrificed and read-outs are ongoing. Preclinical incubation of the remaining macaques covers a range from 6.4 to 7.10 years. Based on the species barrier and an incubation time of > 5 years for BSE in macaques and about 10 years for scrapie in macaques, we expected an onset of clinical disease beyond 6 years post inoculation. 
PRION 2017 DECIPHERING NEURODEGENERATIVE DISORDERS ABSTRACTS REFERENCE
8. Even though human TSE‐exposure risk through consumption of game from European cervids can be assumed to be minor, if at all existing, no final conclusion can be drawn due to the overall lack of scientific data. In particular the US data do not clearly exclude the possibility of human (sporadic or familial) TSE development due to consumption of venison. The Working Group thus recognizes a potential risk to consumers if a TSE would be present in European cervids. It might be prudent considering appropriate measures to reduce such a risk, e.g. excluding tissues such as CNS and lymphoid tissues from the human food chain, which would greatly reduce any potential risk for consumers. However, it is stressed that currently, no data regarding a risk of TSE infections from cervid products are available.


SATURDAY, FEBRUARY 23, 2019 

Chronic Wasting Disease CWD TSE Prion and THE FEAST 2003 CDC an updated review of the science 2019


TUESDAY, NOVEMBER 04, 2014 

Six-year follow-up of a point-source exposure to CWD contaminated venison in an Upstate New York community: risk behaviours and health outcomes 2005–2011

Authors, though, acknowledged the study was limited in geography and sample size and so it couldn't draw a conclusion about the risk to humans. They recommended more study. Dr. Ermias Belay was the report's principal author but he said New York and Oneida County officials are following the proper course by not launching a study. "There's really nothing to monitor presently. No one's sick," Belay said, noting the disease's incubation period in deer and elk is measured in years. "


Transmission Studies

Mule deer transmissions of CWD were by intracerebral inoculation and compared with natural cases {the following was written but with a single line marked through it ''first passage (by this route)}....TSS

resulted in a more rapidly progressive clinical disease with repeated episodes of synocopy ending in coma. One control animal became affected, it is believed through contamination of inoculum (?saline). Further CWD transmissions were carried out by Dick Marsh into ferret, mink and squirrel monkey. Transmission occurred in ALL of these species with the shortest incubation period in the ferret.

snip.... 


Prion Infectivity in Fat of Deer with Chronic Wasting Disease▿ 

Brent Race#, Kimberly Meade-White#, Richard Race and Bruce Chesebro* + Author Affiliations

In mice, prion infectivity was recently detected in fat. Since ruminant fat is consumed by humans and fed to animals, we determined infectivity titers in fat from two CWD-infected deer. Deer fat devoid of muscle contained low levels of CWD infectivity and might be a risk factor for prion infection of other species. 


Prions in Skeletal Muscles of Deer with Chronic Wasting Disease 

Here bioassays in transgenic mice expressing cervid prion protein revealed the presence of infectious prions in skeletal muscles of CWD-infected deer, demonstrating that humans consuming or handling meat from CWD-infected deer are at risk to prion exposure. 


*** 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”

From: TSS 

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

-----Original Message-----

From: Sent: Sunday, September 29, 2002 10:15 AM


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***,

snip... full text ; 


> However, to date, no CWD infections have been reported in people. 

sporadic, spontaneous CJD, 85%+ of all human TSE, did not just happen. never in scientific literature has this been proven.

if one looks up the word sporadic or spontaneous at pubmed, you will get a laundry list of disease that are classified in such a way;



key word here is 'reported'. science has shown that CWD in humans will look like sporadic CJD. SO, how can one assume that CWD has not already transmitted to humans? they can't, and it's as simple as that. from all recorded science to date, CWD has already transmitted to humans, and it's being misdiagnosed as sporadic CJD. ...terry 

*** LOOKING FOR CWD IN HUMANS AS nvCJD or as an ATYPICAL CJD, LOOKING IN ALL THE WRONG PLACES $$$ ***

> However, to date, no CWD infections have been reported in people.
key word here is ‘reported’. science has shown that CWD in humans will look like sporadic CJD. SO, how can one assume that CWD has not already transmitted to humans? they can’t, and it’s as simple as that. from all recorded science to date, CWD has already transmitted to humans, and it’s being misdiagnosed as sporadic CJD. …terry
*** LOOKING FOR CWD IN HUMANS AS nvCJD or as an ATYPICAL CJD, LOOKING IN ALL THE WRONG PLACES $$$ ***
*** 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).***
CWD TSE PRION AND ZOONOTIC, ZOONOSIS, POTENTIAL

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@ References: <3daf5023 .4080804="" wt.net="">

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 =============== 


''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

Consumption of venison and veal was much less widespread among both cases and controls. For both of these meats there was evidence of a trend with increasing frequency of consumption being associated with increasing risk of CJD. (not nvCJD, but sporadic CJD...tss) These associations were largely unchanged when attention was restricted to pairs with data obtained from relatives. ...

Table 9 presents the results of an analysis of these data.

There is STRONG evidence of an association between ‘’regular’’ veal eating and risk of CJD (p = .0.01).

Individuals reported to eat veal on average at least once a year appear to be at 13 TIMES THE RISK of individuals who have never eaten veal.

There is, however, a very wide confidence interval around this estimate. There is no strong evidence that eating veal less than once per year is associated with increased risk of CJD (p = 0.51).

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).

There is some evidence that risk of CJD INCREASES WITH INCREASING FREQUENCY OF LAMB EATING (p = 0.02).

The evidence for such an association between beef eating and CJD is weaker (p = 0.14). When only controls for whom a relative was interviewed are included, this evidence becomes a little STRONGER (p = 0.08).

snip...

It was found that when veal was included in the model with another exposure, the association between veal and CJD remained statistically significant (p = < 0.05 for all exposures), while the other exposures ceased to be statistically significant (p = > 0.05).

snip...

In conclusion, an analysis of dietary histories revealed statistical associations between various meats/animal products and INCREASED RISK OF CJD. When some account was taken of possible confounding, the association between VEAL EATING AND RISK OF CJD EMERGED AS THE STRONGEST OF THESE ASSOCIATIONS STATISTICALLY. ...

snip...

In the study in the USA, a range of foodstuffs were associated with an increased risk of CJD, including liver consumption which was associated with an apparent SIX-FOLD INCREASE IN THE RISK OF CJD. By comparing the data from 3 studies in relation to this particular dietary factor, the risk of liver consumption became non-significant with an odds ratio of 1.2 (PERSONAL COMMUNICATION, PROFESSOR A. HOFMAN. ERASMUS UNIVERSITY, ROTTERDAM). (???...TSS)

snip...see full report ;




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...see full text;

MONDAY, FEBRUARY 25, 2019

***> MAD DOGS AND ENGLISHMEN BSE, SCRAPIE, CWD, CJD, TSE PRION A REVIEW 2019


***> ''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).''

***> In conclusion, sensory symptoms and loss of reflexes in Gerstmann-Sträussler-Scheinker syndrome can be explained by neuropathological changes in the spinal cord. We conclude that the sensory symptoms and loss of lower limb reflexes in Gerstmann-Sträussler-Scheinker syndrome is due to pathology in the caudal spinal cord. <***

***> The clinical and pathological presentation in macaques was mostly atypical, with a strong emphasis on spinal cord pathology.<*** 

***> The notion that CWD can be transmitted orally into both new-world and old-world non-human primates asks for a careful reevaluation of the zoonotic risk of CWD. <***

***> All animals have variable signs of prion neuropathology in spinal cords and brains and by supersensitive IHC, reaction was detected in spinal cord segments of all animals.<*** 

***> In particular the US data do not clearly exclude the possibility of human (sporadic or familial) TSE development due to consumption of venison. The Working Group thus recognizes a potential risk to consumers if a TSE would be present in European cervids.'' Scientific opinion on chronic wasting disease (II) <***



***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 

O.05: Transmission of prions to primates after extended silent incubation periods: Implications for BSE and scrapie risk assessment in human populations 
Emmanuel Comoy, Jacqueline Mikol, Valerie Durand, Sophie Luccantoni, Evelyne Correia, Nathalie Lescoutra, Capucine Dehen, and Jean-Philippe Deslys Atomic Energy Commission; Fontenay-aux-Roses, France 

Prion diseases (PD) are the unique neurodegenerative proteinopathies reputed to be transmissible under field conditions since decades. The transmission of Bovine Spongiform Encephalopathy (BSE) to humans evidenced that an animal PD might be zoonotic under appropriate conditions. Contrarily, in the absence of obvious (epidemiological or experimental) elements supporting a transmission or genetic predispositions, PD, like the other proteinopathies, are reputed to occur spontaneously (atpical animal prion strains, sporadic CJD summing 80% of human prion cases). 

Non-human primate models provided the first evidences supporting the transmissibiity of human prion strains and the zoonotic potential of BSE. Among them, cynomolgus macaques brought major information for BSE risk assessment for human health (Chen, 2014), according to their phylogenetic proximity to humans and extended lifetime. We used this model to assess the zoonotic potential of other animal PD from bovine, ovine and cervid origins even after very long silent incubation periods. 

*** We recently observed the direct transmission of a natural classical scrapie isolate to macaque after a 10-year silent incubation period, 

***with features similar to some reported for human cases of sporadic CJD, albeit requiring fourfold long incubation than BSE. Scrapie, as recently evoked in humanized mice (Cassard, 2014), 

***is the third potentially zoonotic PD (with BSE and L-type BSE), 

***thus questioning the origin of human sporadic cases. 

We will present an updated panorama of our different transmission studies and discuss the implications of such extended incubation periods on risk assessment of animal PD for human health. 

=============== 

***thus questioning the origin of human sporadic cases*** 

=============== 

***our findings suggest that possible transmission risk of H-type BSE to sheep and human. Bioassay will be required to determine whether the PMCA products are infectious to these animals. 

============== 

https://prion2015.files.wordpress.com/2015/05/prion2015abstracts.pdf 

***Transmission data also revealed that several scrapie prions propagate in HuPrP-Tg mice with efficiency comparable to that of cattle BSE. While the efficiency of transmission at primary passage was low, subsequent passages resulted in a highly virulent prion disease in both Met129 and Val129 mice. 

***Transmission of the different scrapie isolates in these mice leads to the emergence of prion strain phenotypes that showed similar characteristics to those displayed by MM1 or VV2 sCJD prion. 

***These results demonstrate that scrapie prions have a zoonotic potential and raise new questions about the possible link between animal and human prions. 

http://www.tandfonline.com/doi/abs/10.1080/19336896.2016.1163048?journalCode=kprn20 

PRION 2016 TOKYO

Saturday, April 23, 2016

SCRAPIE WS-01: Prion diseases in animals and zoonotic potential 2016

Prion. 10:S15-S21. 2016 ISSN: 1933-6896 printl 1933-690X online

Taylor & Francis

Prion 2016 Animal Prion Disease Workshop Abstracts

WS-01: Prion diseases in animals and zoonotic potential

Transmission of the different scrapie isolates in these mice leads to the emergence of prion strain phenotypes that showed similar characteristics to those displayed by MM1 or VV2 sCJD prion. 

These results demonstrate that scrapie prions have a zoonotic potential and raise new questions about the possible link between animal and human prions. 

http://www.tandfonline.com/doi/abs/10.1080/19336896.2016.1163048?journalCode=kprn20

Title: Transmission of scrapie prions to primate after an extended silent incubation period) 

*** In complement to the recent demonstration that humanized mice are susceptible to scrapie, we report here the first observation of direct transmission of a natural classical scrapie isolate to a macaque after a 10-year incubation period. Neuropathologic examination revealed all of the features of a prion disease: spongiform change, neuronal loss, and accumulation of PrPres throughout the CNS. 

*** This observation strengthens the questioning of the harmlessness of scrapie to humans, at a time when protective measures for human and animal health are being dismantled and reduced as c-BSE is considered controlled and being eradicated. 

*** Our results underscore the importance of precautionary and protective measures and the necessity for long-term experimental transmission studies to assess the zoonotic potential of other animal prion strains. 

http://www.ars.usda.gov/research/publications/publications.htm?SEQ_NO_115=313160

GAME FARM INDUSTRY WANTS TO COVER UP FINDINGS OF INCREASE RISK TO CJD FROM CERVID

BSE INQUIRY

CJD9/10022

October 1994

Mr R.N. Elmhirst Chairman British Deer Farmers Association Holly Lodge Spencers Lane 

BerksWell Coventry CV7 7BZ

Dear Mr Elmhirst,

CREUTZFELDT-JAKOB DISEASE (CJD) SURVEILLANCE UNIT REPORT

Thank you for your recent letter concerning the publication of the third annual report from the CJD Surveillance Unit. I am sorry that you are dissatisfied with the way in which this report was published.

The Surveillance Unit is a completely independant outside body and the Department of Health is committed to publishing their reports as soon as they become available. In the circumstances it is not the practice to circulate the report for comment since the findings of the report would not be amended.. In future we can ensure that the British Deer Farmers Association receives a copy of the report in advance of publication.

The Chief Medical Officer has undertaken to keep the public fully informed of the results of any research in respect of CJD. This report was entirely the work of the unit and was produced completely independantly of the the Department.

The statistical results regarding the consumption of venison was put into perspective in the body of the report and was not mentioned at all in the press release. Media attention regarding this report was low key but gave a realistic presentation of the statistical findings of the Unit. This approach to publication was successful in that consumption of venison was highlighted only once by the media ie. in the News at one television proqramme.

I believe that a further statement about the report, or indeed statistical links between CJD and consumption of venison, would increase, and quite possibly give damaging credence, to the whole issue. From the low key media reports of which I am aware it seems unlikely that venison consumption will suffer adversely, if at all. 

http://web.archive.org/web/20030511010117/http://www.bseinquiry.gov.uk/files/yb/1994/10/00003001.pdf

Recently the question has again been brought up as to whether scrapie is transmissible to man. This has followed reports that the disease has been transmitted to primates. One particularly lurid speculation (Gajdusek 1977) conjectures that the agents of scrapie, kuru, Creutzfeldt-Jakob disease and transmissible encephalopathy of mink are varieties of a single "virus". The U.S. Department of Agriculture concluded that it could "no longer justify or permit scrapie-blood line and scrapie-exposed sheep and goats to be processed for human or animal food at slaughter or rendering plants" (ARC 84/77)" The problem is emphasized by the finding that some strains of scrapie produce lesions identical to the once which characterize the human dementias"

Whether true or not. the hypothesis that these agents might be transmissible to man raises two considerations. First, the safety of laboratory personnel requires prompt attention. Second, action such as the "scorched meat" policy of USDA makes the solution of the scrapie problem urgent if the sheep industry is not to suffer grievously.

snip...

76/10.12/4.6

http://web.archive.org/web/20010305223125/www.bseinquiry.gov.uk/files/yb/1976/10/12004001.pdf

IN CONFIDENCE

SCRAPIE TRANSMISSION TO CHIMPANZEES

IN CONFIDENCE

reference...

RB3.20

TRANSMISSION TO CHIMPANZEES

1. Kuru and CJD have been successfully transmitted to chimpanzees but scrapie and TME have not.

2. We cannot say that scrapie will not transmit to chimpanzees. There are several scrapie strains and I am not aware that all have been tried (that would have to be from mouse passaged material). Nor has a wide enough range of field isolates subsequently strain typed in mice been inoculated by the appropriate routes (i/c, ilp and i/v) :

3. I believe the proposed experiment to determine transmissibility, if conducted, would only show the susceptibility or resistance of the chimpanzee to infection/disease by the routes used and the result could not be interpreted for the predictability of the susceptibility for man. Proposals for prolonged oral exposure of chimpanzees to milk from cattle were suggested a long while ago and rejected.

4. In view of Dr Gibbs' probable use of chimpazees Mr Wells' comments (enclosed) are pertinent. I have yet to receive a direct communication from Dr Schellekers but before any collaboration or provision of material we should identify the Gibbs' proposals and objectives.

5. A positive result from a chimpanzee challenged severely would likely create alarm in some circles even if the result could not be interpreted for man. I have a view that all these agents could be transmitted provided a large enough dose by appropriate routes was given and the animals kept long enough. Until the mechanisms of the species barrier are more clearly understood it might be best to retain that hypothesis.

6. A negative result would take a lifetime to determine but that would be a shorter period than might be available for human exposure and it would still not answer the question regarding mans' susceptibility. In the meantime no doubt the negativity would be used defensively. It would however be counterproductive if the experiment finally became positive. We may learn more about public reactions following next Monday' s meeting.

R. Bradley

23 September 1990

CVO (+Mr Wells' comments)

Dr T W A Little

Dr B J Shreeve

90/9.23/1.1.

http://web.archive.org/web/20090506041740/http://www.bseinquiry.gov.uk/files/yb/1990/09/23001001.pdf

IN CONFIDENCE CHIMPANZEES

CODE 18-77 Reference RB3.46

Some further information that may assist in decision making has been gained by discussion with Dr Rosalind Ridley.

She says that careful study of Gajdusek's work shows no increased susceptibility of chimpanzees over New World Monkeys such as Squirrel Monkeys. She does not think it would tell you anything about the susceptibility to man. Also Gajdusek did not, she believes, challenge chimpanzees with scrapie as severely as we did pigs and we know little of that source of scrapie. Comparisons would be difficult. She also would not expect the Home Office to sanction such experiments here unless there was a very clear and important objective that would be important for human health protection. She doubted such a case could be made. If this is the case she thought it would be unethical to do an experiment abroad because we could not do it in our own country.

Retrospectively she feels they should have put up more marmosets than they did. They all remain healthy. They would normally regard the transmission as negative if no disease resulted in five years.

We are not being asked for a decision but I think that before we made one we should gain as much knowledge as we can. If we decided to proceed we would have to bear any criticisms for many years if there was an adverse view by scientists or ­media. This should not be undertaken lightly. There is already some adverse comment here, I gather, on the pig experiment though that will subside.

The Gibbs' (as' distinct from Schellekers') study is somewhat different. We are merely supplying material for comparative studies in a laboratory with the greatest experience of human SEs in the world and it has been sanctioned by USDA (though we do not know for certain yet if chimpanzees specifically will be used). This would keep it at a lower profile than if we conducted such an experiment in the UK or Europe.

I consider we must have very powerful and defendable objectives to go beyond Gibbs' proposed experiments and should not initiate others just because an offer has been made.

Scientists have a responsibility to seek other methods of investigative research other than animal experimentation. At present no objective has convinced me we need to do research using Chimpanzees - a species in need of protection. Resisting such proposals would enable us to communicate that information to the scientist and the public should the need arise. A line would have been drawn.

CVO cc Dr T Dr B W A Little Dr B J Shreeve

R Bradley

26 September 1990

90/9.26/3.2

http://web.archive.org/web/20090506041605/http://www.bseinquiry.gov.uk/files/yb/1990/09/26003001.pdf

this is tse prion political theater here, i.e. what i call TSE PRION POKER...tss

http://web.archive.org/web/20031028205208/www.bseinquiry.gov.uk/files/yb/1990/08/28002001.pdf

http://web.archive.org/web/20030822170317/www.bseinquiry.gov.uk/files/yb/1990/11/01005001.pdf

3. Prof. A. Robertson gave a brief account of BSE. The US approach was to accord it a very low profile indeed. Dr. A Thiermann showed the picture in the ''Independent'' with cattle being incinerated and thought this was a fanatical incident to be avoided in the US at all costs.

snip...

PAGE 26

Transmission Studies

Mule deer transmissions of CWD were by intracerebral inoculation and compared with natural cases {the following was written but with a single line marked through it ''first passage (by this route)}....TSS

resulted in a more rapidly progressive clinical disease with repeated episodes of synocopy ending in coma. One control animal became affected, it is believed through contamination of inoculum (?saline). Further CWD transmissions were carried out by Dick Marsh into ferret, mink and squirrel monkey. Transmission occurred in ALL of these species with the shortest incubation period in the ferret.

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. 

snip...see;

IN CONFIDENCE

PERCEPTIONS OF UNCONVENTIONAL SLOW VIRUS DISEASE OF ANIMALS IN THE USA

GAH WELLS

REPORT OF A VISIT TO THE USA

APRIL-MAY 1989

http://web.archive.org/web/20090506002237/http://www.bseinquiry.gov.uk/files/mb/m11b/tab01.pdf

why do we not want to do TSE transmission studies on chimpanzees $

5. A positive result from a chimpanzee challenged severly would likely create alarm in some circles even if the result could not be interpreted for man. 

***> I have a view that all these agents could be transmitted provided a large enough dose by appropriate routes was given and the animals kept long enough. 

***> Until the mechanisms of the species barrier are more clearly understood it might be best to retain that hypothesis.

snip...

https://web.archive.org/web/20090506041740/http://www.bseinquiry.gov.uk/files/yb/1990/09/23001001.pdf

MONDAY, FEBRUARY 25, 2019

***> MAD DOGS AND ENGLISHMEN BSE, SCRAPIE, CWD, CJD, TSE PRION A REVIEW 2019

https://bseinquiry.blogspot.com/2019/02/mad-dogs-and-englishmen-bse-scrapie-cwd.html

*** The potential impact of prion diseases on human health was greatly magnified by the recognition that interspecies transfer of BSE to humans by beef ingestion resulted in vCJD. While changes in animal feed constituents and slaughter practices appear to have curtailed vCJD, there is concern that CWD of free-ranging deer and elk in the U.S. might also cross the species barrier. Thus, consuming venison could be a source of human prion disease. Whether BSE and CWD represent interspecies scrapie transfer or are newly arisen prion diseases is unknown. Therefore, the possibility of transmission of prion disease through other food animals cannot be ruled out. There is evidence that vCJD can be transmitted through blood transfusion. There is likely a pool of unknown size of asymptomatic individuals infected with vCJD, and there may be asymptomatic individuals infected with the CWD equivalent. ***These circumstances represent a potential threat to blood, blood products, and plasma supplies.

http://cdmrp.army.mil/prevfunded/nprp/NPRP_Summit_Final_Report.pdf

***> 1st and foremost your biggest problem is 'VOLUNTARY'! AS with the BSE 589.2001 FEED REGULATIONS, especially since it is still voluntary with cervid, knowing full well that cwd and scrapie will transmit to pigs by oral route. VOLUNTARY DOES NOT WORK! all animal products should be banned and be made mandatory, and the herd certification program should be mandatory, or you don't move cervid. IF THE CWD HERD CERTIFICATION IS NOT MANDATORY, it will be another colossal tse prion failure from the start.

***> 2nd USA should declare a Declaration of Extraordinary Emergency due to CWD, and all exports of cervid and cervid products must be stopped internationally, and there should be a ban of interstate movement of cervid, until a live cwd test is available.

***> 3rd Captive Farmed cervid ESCAPEES should be made mandatory to report immediately, and strict regulations for those suspect cwd deer that just happen to disappear. IF a cervid escapes and is not found, that farm should be indefinitely shut down, all movement, until aid MIA cervid is found, and if not ever found, that farm shut down permanently.

***> 4th Captive Farmed Cervid, INDEMNITY, NO MORE Federal indemnity program, or what i call, ENTITLEMENT PROGRAM for game farm industry. NO MORE BAIL OUTS FROM TAX PAYERS. if the captive industry can't buy insurance to protect not only themselves, but also their customers, and especially the STATE, from Chronic Wasting Disease CWD TSE Prion or what some call mad deer disease and harm therefrom, IF they can't afford to buy that insurance that will cover all of it, then they DO NOT GET A PERMIT to have a game farm for anything. This CWD TSE Prion can/could/has caused property values to fall from some reports in some places. roll the dice, how much is a state willing to lose?

***> 5th QUARANTINE OF ALL FARMED CAPTIVE, BREEDERS, URINE, ANTLER, VELVET, SPERM, OR ANY FACILITY, AND THEIR PRODUCTS, that has been confirmed to have Chronic Wasting Disease CWD TSE Prion, the QUARANTINE should be for 21 years due to science showing what scrapie can do. 5 years is NOT near long enough. see; Infectious agent of sheep scrapie may persist in the environment for at least 16 to 21 years.

***> 6th America BSE 589.2001 FEED REGULATIONS CWD TSE Prion

***> 7TH TRUCKING TRANSPORTING CERVID CHRONIC WASTING DISEASE TSE PRION VIOLATING THE LACEY ACT

***> 8TH ALL CAPTIVE FARMING CERVID OPERATIONS MUST BE INSURED TO PAY FOR ANY CLEAN UP OF CWD AND QUARANTINE THERE FROM FOR THE STATE, NO MORE ENTITLEMENT PROGRAM FOR CERVID GAME FARMING PAY TO PLAY FOR CWD TSE PRION OFF THE TAX PAYERS BACK.

***> 9TH ANY STATE WITH DOCUMENTED CWD, INTERSTATE, NATIONAL, AND INTERNATIONAL MOVEMENT OF ALL CERVID, AND ALL CERVID PRODUCTS MUST BE HALTED!

***> 10TH BAN THE SALE OF STRAW BRED BUCKS AND ALL CERVID SEMEN AND URINE PRODUCTS

***> 11th ALL CAPTIVE FARMED CERVID AND THEIR PRODUCTS MUST BE CWD TSE PRION TESTED ANNUALLY AND BEFORE SALE FOR CWD TSE PRION

SEE FULL SCIENCE REFERENCES AND REASONINGS ;

Control of Chronic Wasting Disease OMB Control Number: 0579-0189 APHIS-2021-0004 Singeltary Submission



Docket No. APHIS-2018-0011 Chronic Wasting Disease Herd Certification




Published: 06 September 2021

***> Chronic wasting disease: a cervid prion infection looming to spillover

Alicia Otero, Camilo Duque Velásquez, Judd Aiken & Debbie McKenzie 

Veterinary Research volume 52, Article number: 115 (2021) 



FRIDAY, APRIL 30, 2021 

Should Property Evaluations Contain Scrapie, CWD, TSE PRION Environmental Contamination of the land?


WEDNESDAY, DECEMBER 04, 2013 

Chronic Wasting Disease CWD and Land Value concerns? 



TUESDAY, APRIL 13, 2021 

Implications of farmed-cervid movements on the transmission of chronic wasting disease

TRUCKING TRANSPORTING CERVID CHRONIC WASTING DISEASE TSE PRION VIOLATING THE LACEY ACT



MONDAY, MARCH 05, 2018 

TRUCKING AROUND AND SPREADING CHRONIC WASTING DISEASE CWD TSE PRION VIA MOVEMENT OF CERVID AND TRANSPORTATION VEHICLES



SATURDAY, JULY 09, 2016

Texas Intrastate – within state movement of all Cervid or Trucking Chronic Wasting Disease CWD TSE Prion Moratorium




THURSDAY, AUGUST 20, 2015 

TEXAS CAPTIVE Deer Industry, Pens, Breeding, Big Business, Invites Crooks and CWD



THURSDAY, FEBRUARY 17, 2022 

Captive Cervids and their Contribution to CWD 



FRIDAY, FEBRUARY 11, 2022 

Passage of the CWD agent through meadow voles results in increased attack rates and decreased incubation periods in raccoons



Terry S. Singeltary Sr.

posted by Terry S. Singeltary Sr. at 3:24 PM

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