USAHA 117TH ANNUAL MEETING USDA-APHIS–VS CWD Herd Certification Program Goals TSE PRION October 17 – 23, 2013
Goals for CWD Herd Certification Program
Lee Ann Thomas, Ruminant Health Programs, USDA-APHIS–VS
An overview was presented of the voluntary national Chronic Wasting Disease
(CWD) herd certification program for farmed deer, elk, and moose as well as
established minimum standards for interstate movement of cervids. The purpose of
the Herd Certification Program (HCP) is to provide clarification and guidance on
how to comply with and meet requirements of the CWD rule and contains two Parts:
Part A – Herd Certification
and
Part B – Guidance on Response to CWD-affected herds.
Funding for the program is through APHIS-VS Equine, Cervids, Small
Ruminants (ECSR) Commodity Health Line which funds essential activities for
surveillance and program operations with flexibility to respond to new and
emerging health concerns. A review of the FY 2013/14 Program Activities of
APHIS-VS which included federal oversight of the voluntary national CWD HCP as
well as the principle activities conducted that pertain to the HCP. Based on
available resources, APHIS will serve in an advisory capacity to Approved States
for
1) epidemiological investigations of positive findings;
2) development of herd plans (newly infected herds);
3) quarantine, depopulations, cleaning and disinfection; and
4) assistance with annual herd inspections and tri-annual physical herd
inventories.
FY 2013/14 Program Activities required for Approved States included
1) compliance with CWD rule;
2) annual reports;
3) management of HCP data;
4) reporting positive cervid herds to APHIS;
5) respond, investigate, and manage CAPTIVE WILDLIFE AND ALTERNATIVE
LIVESTOCK 169 any positive, suspect, and exposed animals/herds; and 6) develop
herd plans for positive/exposed herds.
The CWD Interim Final Rule (CWD Herd Certification Program and Interstate
Movement of Farmed or Captive Deer, Elk, and Moose) was published in the Federal
Register June 13, 2012 with a public comment period. The effective date of the
rule was August 13, 2012. Part 81 of the Rule delayed enforcement until December
10, 2012. Public comments have been considered and affirmation of a final rule
is in development.
The Revised federal rule applies only to the following genera known to be
susceptible to CWD by natural infection including, Cervus (elk, red deer, sika
deer), Odocoileus (white-tailed deer (WTD), mule deer (MD), black-tailed deer
(BTD) and Alces (moose).
States may have requirements for other cervid species.
The objectives of the CWD rule are to
1) provide uniform minimum requirements for state CWD herd certification
programs (HCPs);
2) provide uniform minimum requirements for interstate movement of CWD
susceptible species;
3) provide a regulatory framework to support domestic and international
markets for farmed cervids and cervid products; and
4) provide a consistent approach towards minimizing risk of introduction
and transmission of CWD in cervid populations.
Provisions of the CWD rule include
1) Part 55 (Subpart A): Indemnity, Laboratory Approval, Official Laboratory
Testing;
2) Part 55 (Subpart B): Voluntary national Approved State CWD HCP for
farmed cervids (deer and elk) (fencing requirements, animal ID and herd
inventory requirements, surveillance - testing mortalities >12 months, and
herd status – based on years of surveillance and participation in HCP),
3) Part 81: Interstate movement minimum requirements ) establishes minimum
requirements for interstate movement of cervids.
*** The CWD rule does not include international movement regulations.
***
States having a CWD HCP may request federal approval of their State program
which will be approved by APHIS in accordance with CWD rule (9 CFR 55.23). As of
October 2013, there are 29 Approved State HCPs. Approved states must have a
signed memorandum of understanding (MOU) with APHIS that addresses
1) authority to restrict animal movement;
2) enforces and monitors quarantines;
3) surveillance and disease reporting capability;
4) animal identification;
5) designated CWD HCP coordinator;
6) mortality surveillance;
7) recordkeeping and data management;
8) ability to conduct epidemiologic investigations;
8) education/ outreach for producers;
9) herd plans (CWD positive/exposed herds);
and
10) annual reports to renew Approved status.
Herd owners already participating in State CWD programs will keep initial
State enrollment date (first date of participation) when State is designated an
Approved State CWD HCP.
There is no available funding projected for FY2014 to support direct herd
owner enrollment in the national program. Herd owners must comply with animal
identification, fencing requirements, reporting REPORT OF THE COMMITTEE 170
escapes & mortalities and mortality testing for certified status, herd
records and inventories, separation from other herds, and status of herd
additions.
A CWD Working Group was formed to review and provide input on revisions to
the CWD Program Standards (2012 USAHA Resolution).
Members included representatives from the cervid industry, state animal
health officials, state wildlife agencies/ Association of Fish and Wildlife
Agencies (AFWA), and diagnostic laboratories (AAVLD/NAHLN), and APHIS-VS.
Meetingwere conducted through weekly teleconferences and topics discussed
included – physical inventory, sample collection, missing samples, reporting
mortalities and escapes, transiting, herd plans, trace outs, animal
identification, fencing, and interstate movement. Further information can be
found at:
http://www.aphis.usda.gov/animal_health/animal_diseases/cwd.
snip...
CAPTIVE WILDLIFE AND ALTERNATIVE LIVESTOCK 171 Committee Business:
There was one resolution presented and passed by the Committee regarding a
National Review of Research Needs for Chronic Wasting Disease.
The resolution was submitted requesting that the USAHA request the USDA,
and the U.S. Department of Interior (DOI) to arrange a diversified blue-ribbon
panel (which would include industry stakeholders, university and federal
researchers, and Federal and State regulatory agencies) to determine research
needs and identify and prioritize intervention strategies for the control of
Chronic Wasting Disease.
The resolution was moved by member Warren Bluntzer and seconded by Glen
Zebarth, and forwarded to the Committee on Nominations and Resolutions.
A recommendation was presented to the Committee on Captive Wildlife and
Alternative Livestock to create a new Committee on farmed cervidae.
The motion to form the new Committee was moved by Richard Winters and
seconded by Paul Anderson.
A vote following discussion was tied 13 to 13. The following is a copy of
the recommendation with some preliminary edits.
It was felt by many of the members that if this Committee was approved that
there should be some significant modifications to the mission statement, which
was proposed as follows:
Background: The farmed cervidae industry is unique in that producers deal
with diseases, regulations and political issues which are unlike any other
animal agricultural industry. To effectively address these issues requires a
national forum for discussion. The creation of a new USAHA committee where
farmed cervidae producers can work together with state and federal regulatory
officials and scientists to solve the problems faced by the industry is
critical.
Mission: “The purpose of the Committee on Farmed Cervidae is to
provide a national forum to (1) discuss scientific, regulatory and political
issues affecting the farmed cervidae industry, (2) evaluate state and federal
regulatory programs, (3) develop effective programs to control diseases, and (4)
recommend regulatory programs that contribute to the growth and prosperity of
the farmed cervidae industry while mitigating disease risks.” The Committee
adjourned at 12:47 p.m.
snip...
Three new Scrapie/chronic wasting disease (CWD) testing platforms have been
approved by NVSL/VS for use in the 21 NAHLN laboratories performing surveillance
to replace the Ventana NexES (being obsoleted). Laboratories may select from:
Biocare Medical’s IntelliPATH FLX®, Leica Microsystem’s BOND MAX, or the Ventana
Discovery XT. NVSL- Pathobiology Laboratory (PL) will continue to provide
standard operating procedures (SOP), proficiency testing (PT), reagent quality
assurance (QA) and confirmatory testing on each of the platforms.
snip...
RESOLUTION NUMBER: 16 - APPROVED SOURCE: COMMITTEE ON CAPTIVE WILDLIFE AND
ALTERNATIVE LIVESTOCK SUBJECT MATTER: NATIONAL REVIEW OF RESEARCH NEEDS FOR
CHRONIC WASTING DISEASE BACKGROUND INFORMATION:
In the absence of an approved
live animal test, vaccine, or recognition of genetically resistant animals,
depopulation and indemnity of the herd mates is NOMINATIONS AND RESOLUTIONS 289
our only method of prevention to stop the spread of Chronic Wasting Disease
(CWD) to other animals. A Federal CWD Rule has been implemented with the purpose
of controlling the spread of CWD versus eradication. To insure a successful
program more tools are needed to manage this disease.
RESOLUTION: The United
States Animal Health Association (USAHA) requests that the United States
Department of Agriculture, and United States Department of Interior arrange a
diversified blue-ribbon panel (including: industry stakeholders, university and
federal researchers, Federal and State regulatory agencies) to determine
research needs and identify and prioritize intervention strategies for the
control of Chronic Wasting Disease.
*****
Chronic Wasting Disease Ecology and Epidemiology of Mule Deer and
White-tailed Deer in Wyoming
Dr. Brant Schumaker of the University of Wyoming reported that the effects
of high chronic wasting disease (CWD) prevalence in free-ranging deer
populations are unknown. In south-central Wyoming, CWD prevalence exceeds 50% in
hunter harvested deer. We hypothesized that 1) vital rates are depressed by CWD
and the finite rate of population growth (λ) is subsequently lowered, 2) CWD
alters normal deer behavior during preclinical and clinical disease, and 3)
genetic differences associated with CWD incubation periods drives natural
selection to favor less susceptible deer. To test these hypotheses, we
radio-collared white-tailed deer (Odocoileus virginianus) and mule deer
(Odocoileus hemionus) and monitored them to determine a) survival probability,
pregnancy rates, and annual recruitment, b) cause of death, c) home range area
and habitat use, d) migration patterns, e) dispersal behavior, and f) genetic
variation in incubation period based on CWD-status. Deer were tested for CWD
using tonsil tissue collected by biopsy at capture and immunohistochemistry.
White-tailed deer positive for CWD were 4.5 times more likely to die annually
compared to CWD-negative deer. High CWD prevalence depressed survival of young
females and resulted in an unsustainable white-tailed deer population (λ <
1.0); however, when female harvest was eliminated, the population became stable
(λ =1.0). Female CWD-positive white-tailed deer maintain locally high CWD
incidence as they migrated less and occupied smaller home ranges compared to
other deer. Male CWD-positive white-tailed deer migrated at the highest
proportion and likely contributed to spread of CWD to disparate populations. In
the last nine years, mule deer genetically associated with prolonged incubation
periods to CWD have increased in frequency in the population. However, it is
still unknown whether or not this change will counteract the negative impacts of
CWD on the population. The white-tailed deer population is adversely affected by
high CWD prevalence; however, implementing management techniques to increase
annual survival of females may maintain deer populations. The impact of CWD on
mule deer populations is currently unknown; however, the present study is in its
final stages with results to be completed in the near future.
*****
b) Scrapie control programs in the U.S. are based in the National Scrapie
Program, which some potential trade partners are not comfortable with. As such,
they rely on the OIE standards as their default measure in disallowing sheep
imports from the U.S. USDA responded that basically they will not be able to
change those National Scrapie Program shortcomings in the short term. USDA will
negotiate with OIE and may effect change by 2015.
*****
RESOLUTION NUMBER: 22 - APPROVED SOURCE: COMMITTEE ON SHEEP AND GOATS
SUBJECT MATTER: SEPARATE SHEEP AND GOAT COMMODITY HEALTH LINE ITEM BACKGROUND
INFORMATION:
In FY2011, the United States Department of Agriculture (USDA),
Animal and Plant Health Inspection Service (APHIS), Veterinary Services (VS)
primarily addressed sheep and goat health/disease issues through the National
Scrapie Eradication Program (NSEP) and National Animal Health Monitoring System
(NAHMS) studies. For FY2012, USDA-APHIS-VS requested that Congress approve
commodity-based funding which would include horses, cervids, sheep, and goats in
a single line item where funding could be transferred between the commodities
based on priorities identified by USDA-APHIS-VS and its partners. The proposed
grouping of these species is reminiscent of the failed Miscellaneous Diseases
line item in the USDA-APHIS-VS budget of over 20 years ago.
*****
Health Association is concerned that sheep and goat funding may be diverted
to address needs of other species, which could jeopardize the eradication of
scrapie from the United States and the health and well-being of sheep and goats.
The currently proposed species grouping of Equines, Cervids, and Small Ruminants
(sheep and goats) is not appropriate to serve the health and disease needs of
such a diverse group of animals. Equines and Cervids have very few common health
and disease issues with Sheep and Goats. Emerging diseases in each of the
species in the proposed grouping will most likely result in even less
commonality in disease/health priorities among these species.
RESOLUTION: The
United States Animal Health Association (USAHA) urges the United States
Department of Agriculture (USDA), Animal and Plant Health Inspection Service
(APHIS), Veterinary Services (VS) to establish a separate funding line item for
Sheep and Goat Health.
*****
Leafstedt, SD; Mary Lis, CT; Jim Logan, WY; Michael Marshall, UT; Shirley
McKenzie, NC; Cheryl Miller, IN; Ronald Miller, PA; Elisabeth Patton, WI; Jewell
Plumley, WV; Justin Roach, OK; Suelee Robbe-Austerman, IA; Paul Rodgers, WV;
Joan Dean Rowe, NC; Ben Smith, WA; Scott Stuart, CO; Diane Sutton, MD; Manoel
Tamassia, NJ; Stephen White, WA; Nora Wineland, MO; David Winters, TX; Cindy
Wolf, MN. The Committee met on October 22, 2013 at the Town and Country Hotel,
San Diego, California, from 9:00 to 11:46 a.m.
There were 12 members and 9 guests present.
The meeting began with a review of the of the Committee purpose. Attendees
did not elect to make any changes to the current language. The following
presentations and reports were given.
USDA-APHIS Scrapie Program Update and Scrapie Surveillance Projects Alan
Huddleston, Associate National Scrapie Program Director United States Department
of Agriculture, Animal and Plant Health Inspection Service, Veterinary Services
(USDA-APHIS-VS) (Presented by TJ Myers Associate Deputy Administrator,
USDA-APHIS-VS) Scrapie Eradication Program Results
• There has been a 90 percent decrease in the percent positive sheep
sampled at slaughter adjusted for face color, from 0.15 to 0.015 percent, since
the start of Regulatory Scrapie Slaughter Surveillance (RSSS) in FY 2003 thru
September 30, 2013.
• There were 11 new infected or source flocks reported in FY 2013 as of
September 30, 2013. FY 2013 is the first year since FY 2005 when a reduction in
the number of new scrapie infected and source flocks was not observed. Now that
the program is in the tail end of the eradication effort it is likely that the
numbers will go up and down from year to year due to the difficulty in
accurately measuring the frequency of uncommon events. Slaughter Surveillance
• The number of animals sampled through slaughter surveillance in FY 2013,
through September 30, 2013 was 42,888 compared to 40,776 in FY 2012; this
represents an increase of 5 percent. The increase was due to increased sampling
of goats. Scrapie Surveillance Plan
• Implementation o States with regulatory scrapie slaughter surveillance
(RSSS) collection sites will continue to sample all targeted sheep and goats.
REPORT OF THE COMMITTEE 340
o States have State-of-origin sampling minimums for
sheep.
o VS plans to require annual State-of-origin sampling minimum for goats
to be met once the proposed rule revising title 9, Code of Federal Regulations
(9 CFR) parts 54 and 79 is finalized. Proposed sampling minimums were provided
for FY 2013 and FY 2014.
o The annual State-of-origin sampling minimum for sheep
is 20 percent of the number required to detect a scrapie prevalence of 0.1
percent with 95 percent confidence or 1 percent of the breeding flock in the
State, whichever is less. The objective is to sample sufficient sheep in a
5-year period to detect a scrapie prevalence of 0.1 percent with 95 percent
confidence or 5 percent of the breeding flock in the State, whichever is less.
o
The annual State-of-origin sampling minimum for goats is determined based on the
States’ goat scrapie case incidence. o If a State has not had a goat scrapie
case in the previous ten years, its annual goat sampling minimum is its prorated
share of 3,000 samples, based on its proportion of the U.S. goat population as
determined by the National Agricultural Statistics Survey (NASS) Sheep and Goat
annual report.
o If a State has had a goat scrapie case in the previous ten
years, its annual goat sampling minimum is determined using the same method as
is used for determining its annual sheep sampling minimum.
o Beginning in FY
2013, sheep and goat sampling minimums were calculated separately. As a result,
a higher percentage of States will not achieve their sheep sampling minimums in
FY 2013 compared with FY 2012. Approximately 40% will not achieve the sheep
sampling minimums this fiscal year, compared to approximately 20% in FY 2012.
States that did not meet their sheep sampling minimum in FY 2013 through RSSS
but will be expected to find other sampling sources to meet the minimum in FY
2014.
Note: These are minimums. Plans are to continue to collect samples from
the maximum number of targeted animals given the available budget.
FY 2014 Priorities
• VS priorities for scrapie are to focus on improving the effectiveness and
cost efficiency of surveillance and to increase animal identification
compliance. This will be accomplished in part by publishing a proposed rule that
would address gaps in identification and require States to meet reasonable
surveillance targets to remain consistent States. States must meet these targets
for VS to demonstrate geographically appropriate surveillance to meet the
criteria for freedom and have confidence that all of the remaining cases have
been found.
• The rule would propose to: SCRAPIE 341
o Give the APHIS Administrator
authority to relieve requirements for sheep and goats exposed to scrapie types,
such as Nor98-like, that do not pose a significant risk of transmission;
o Increase flexibility in how investigations can be conducted and allow the
epidemiology in a specific flock to be given more consideration in determining
flock and animal status;
o Add a genetic-based approach to regulation;
o Make goat identification requirements similar to those for sheep to
support ongoing slaughter surveillance in goats (no changes will be made in the
consistent State requirements regarding identification of goats in intrastate
commerce);
o Tighten the definition of slaughter channels;
o Expand the individual
identification requirement to all sexually intact animals unless moving as a
group/lot (allows mixed-source groups moving in slaughter channels under 18
months);
o Limit the use of tattoos and implants to animals not moving through
markets and not in slaughter channels;
and
o Reduce recordkeeping requirements by making them similar to the current
uniform methods and rules compliance guidance.
• APHIS is also revising its scrapie import regulations to bring them more
in line with the World Animal Health Organization (OIE) scrapie chapter. This
will ensure that we meet OIE criteria for free status and prevent the
reintroduction of scrapie after free status is achieved. Scrapie Flock
Certification Program (SFCP) Standards On May 3, 2013 APHIS announced its
intention to revise the SFCP. The comment period closed June 3, and the revised
program has gone into effect. The SFCP standards were revised to increase the
program’s ability to identify infected flocks quicker and to prevent infected
flocks from becoming certified, to reduce costs associated with the program, and
to increase SFCP contribution to scrapie surveillance. Scrapie program staff
collected input from SFCP enrolled producers, industry representatives, and
State and federal stakeholders. The public had a final opportunity to comment on
the revised standards through a Federal Register notice. In the revised SFCP the
Complete category is eliminated. Additionally, the Select category is revised,
and the Export category is slightly modified.
• Select category: APHIS has redirected monitoring from inspections to
sampling. Select category flocks do not become certified. Specifics for this
category include:
o There are no annual inspections.
o Owners must report clinical signs of scrapie.
o Herd owners follow 9 CFR 79 requirements for recordkeeping and animal ID
for their flocks.
o Flock owners can acquire animals from any other flock, whether or not
REPORT OF THE COMMITTEE 342
that flock is enrolled in the SFCP.
o The sampling and testing requirements include:
Sheep or goats displaying clinical signs over 12 months of age;
Animals of any age that either test suspect, inconclusive or positive on a
live animal scrapie test or have been determined to be a scrapie suspect by a
State, Federal or accredited veterinarian;
and
A minimum of one animal per 1-3
years, depending on flock size.
• Export Category:
APHIS continues a high level of monitoring including
inspections and sampling. Flocks can become Export Certified. Specifics for this
category include:
o Annual inspections are required.
o Owners must report clinical signs of scrapie.
o Animals must be identified with official SFCP ID. o Flock owners must
meet rigorous recordkeeping requirements including maintaining records on every
animal that leaves the flock for seven years.
o Flock owners must have all cull animals inspected, including home
slaughtered animals, for clinical signs of scrapie at least 30 days before
culling.
o Flock owners can acquire female animals and embryos only from other
Export category flocks of equal or higher status.
o Flock owners can use sheep and goat milk and colostrum and sheep and goat
milk- and colostrum-derived products only from within their own flock or from
other Export category flocks of equal or higher status.
o The sampling and testing requirements include:
Sheep or goats displaying clinical signs over 12 months of age;
Animals of any age that either test suspect, inconclusive or positive on a
live animal scrapie test or have been determined to be a scrapie suspect by a
State, Federal or accredited veterinarian;
All found dead mature animals, including euthanized animals;
An annual sampling minimum of one test eligible animal tested for each year
of status held (A flock will be removed from the program if the flock owner
fails to submit at least one test eligible animal for two consecutive years.);
To gain six years in status, 15 test eligible animals must be sampled; and
The requirements for Export Certified status include:
seven years in status; and
Meet one of three sampling protocols o Standard: 30 test eligible animals o
Alternative
1: test all genetically susceptible animals sold SCRAPIE 343
o Alternative
2: test all foundation flock animals.
• Participants in the Complete category had the following options:
(1) join the Export category with up to 5 years of status;
(2) join the revised Select category; or
(3) withdraw from the program.
o For participants who held “Certified” status in the Complete category who
convert to the Export category, APHIS will continue to publish their “Certified”
status on its website for 3 years following the start date of the revised
program, in addition to their new “Export Monitored” status, to allow them
sufficient time to become Export Certified; and
o If instead they convert to the Select category or withdraw from the
program, APHIS will not continue to publish their “Certified” status on its
website.
Scrapie Surveillance Projects:
• Since the start of slaughter surveillance in 2003 the prevalence of
scrapie in sheep has declined 85 percent from 0.2 percent to less than 0.03
percent. The prevalence in goats is estimated to be less than 0.02 percent.
• APHIS continues to find new approaches to increase flock level
surveillance.
• In FY 2013 APHIS initiated an effort to provide information on sample
collection and to encourage producer and accredited veterinarian submission of
samples.
• Instructions for producers and veterinarians to submit samples are now
available on the APHIS Scrapie Web Page.
• In FY 2014 APHIS will conduct pilot projects in New Jersey and Arkansas
to evaluate the efficiency of working with accredited veterinarians to collect
samples for scrapie testing.
Update from Agriculture Research Service David Schneider USDA, Agriculture
Research Service (ARS), Animal Disease Research Unit (ADRU)
The USDA-ARS unit in Pullman, Washington, conducts an integrated research
program involving studies on scrapie transmission, diagnosis and susceptibility
genetics in domestic sheep and goats. Accumulation of disease-associated prion
protein (PrPSc) in the placenta of sheep is a recognized source for natural
transmission of classical scrapie disease and environmental contamination. Much
less is known about prion accumulation in the placenta of goats but our recent
study demonstrated much less PrPSc accumulates in the placenta in goats, which
calls into question its role in natural transmission. In a recent follow-up
study, we now demonstrate that the placenta of goats does harbor prions
infectious to other goats and sheep when exposed by the oral route. A study on
Nor98-like scrapie in breeding ewes is now in its 6th year.
REPORT OF THE COMMITTEE 344 Ewes were experimentally inoculated with brain
homogenate obtained from a U.S. sheep with clinical Nor98-like scrapie.
Recipient ewes are bred annually to examine the placenta for evidence of a
transmissible agent. Placentas shed 2009-2013 were negative.
*** In 2013, one recipient ewe developed an unrelated disease. At
postmortem examination, abundant accumulation of PrPSc was observed only in the
cerebellum of this ewe with much less accumulation in the hindbrain obex. This
confirms that initial inoculation of these ewes has been successful. Monitoring
continues in the remaining ewes of this study.
Improvements in tissue-based (rectal biopsy) live animal testing for
scrapie with focus on application to goats continue. In addition, efforts toward
developing a live-animal blood test have demonstrated the presence of prions
(infectivity) in the blood of sheep and goats, even those with preclinical
disease and within blood sample volumes routinely used in veterinary diagnostic
work. A recent study also demonstrates PrPSc accumulation in lymphoid tissues of
hemal nodes, small lymphoid organs that filter blood but not lymph.
Collectively, these findings confirm that blood is a relevant target for
continued assay development. We continue to develop methods for enriching the
relevant blood fractions for assay and are now making efforts to adapt novel in
vitro assays for detecting infectivity and prion-associated misfolding activity.
A long term study examining the effect of prion genotype on susceptibility
to goat scrapie and the effect of genetic changes on accuracy of live animal
testing continue. Following oral infection at birth with placenta and
brain-derived scrapie, goats with the highly susceptible genotype all developed
clinical disease around 24 months. Goats with the less susceptible or long
incubation genetics today remain clinically normal. Monitoring continues.
Prion Transmission Through Milk Christina Sigurdson University of
California, San Diego School of Medicine, Department of Pathology Prion
disorders are caused by misfolded proteins that are naturally transmitted,
causing a fatal neurological disease in animals. In sheep with classical
scrapie, prions accumulate in the follicles of lymphoid tissues in addition to
the brain and spinal cord. Follicular dendritic cells (FDCs) form a network
within the follicles and accumulate high levels of prions during disease.
Previous work in mice has revealed that follicular inflammation in non-lymphoid
organs, such as kidney, results in prion accumulation and can lead to prion
shedding, such as into the urine. We have found sheep with follicular mastitis
and scrapie that have accumulated prions within the follicles of the mammary
gland. In follow-up studies, we found that sheep with scrapie and lentiviral
mastitis secrete prions into the milk and infect nearly 90% of naïve suckling
lambs. Taken together, lentiviruses may enhance prion transmission and
conceivably sustain prion infections in flocks for generations. Work by other
groups has also shown prion infectivity in all three milk fractions, cells,
casein whey, and SCRAPIE 345 cream. Prion infectivity has also been detected in
milk from sheep having the VRQ/VRQ genotype with no evidence of mastitis.
References 1. Konold, T., Moore, S.J., Bellworthy, S.J. & Simmons, H.A.
Evidence of scrapie transmission via milk. BMC Vet Res 4, 14 (2008). 2. Konold,
T., et al. Evidence of effective scrapie transmission via colostrum and milk in
sheep. BMC Vet Res 9, 99 (2013). 3. Ligios, C., et al. Sheep with Scrapie and
Mastitis Transmit Infectious Prions through the Milk. J Virol 85, 1136-1139
(2011). 4. Ligios, C., et al. PrPSc in mammary glands of sheep affected by
scrapie and mastitis. Nat Med 11, 1137-1138 (2005). 5. Lacroux, C., et al.
Prions in milk from ewes incubating natural scrapie. PLoS Pathog 4, e1000238
(2008).
Committee Business: The final response from the Committee’s 2012 Resolution
(26, 9 and 30 Combined) relating to the export of sheep and goats was reviewed.
In this response the USDA-APHIS-VS agreed to ask the World Organization for
Animal Health (OIE) to modify the Scrapie Chapter to consider options such as
genotyping to qualify animals for export. USDA-APHIS-VS agreed to make this
request by Spring 2014, and would expect to see the Scrapie Chapter amended in
Spring 2015 or 2016 if their revisions were to be accepted by OIE. One of the
Committee members updated the group on progress related to a 2010 Resolution
#48. This resolution requested USDA, Food Safety Inspection Service (FSIS) to
work with USDA-APHIS-VS and industry to identify and approve appropriate sites
for radio frequency identification implants for goats and sheep. As a result,
both the underside of the tail and the base of the ear are now approved sites
for these implants. No new resolutions or recommendations were introduced. The
Committee briefly discussed the challenges of obtaining scrapie surveillance
samples from certain flocks and herds. Several members mentioned that one
barrier to sample collection is the problem that the producers have with carcass
disposal after the head has been removed. Members agreed that offering options
to producers to help them properly dispose of these carcasses could
significantly increase voluntary participation in surveillance. Options include
to transporting carcasses to diagnostic laboratories or providing payment to the
producers to offset the cost of carcass disposal.
snip...
Regulatory Updates for Sheep and Goat Importations Joyce Bowling-Heyward,
NCIE, USDA-APHIS Discussion initiated with discussion of bovine spongiform
encephalopathy (BSE), Scrapie and other Transmissible spongiform
encephalopathies (TSEs) in Ruminants, and impact on regulations concerning
these. Schmallenburg Virus and potential for incursion was discussed, and need
for surveillance and vigilance. A complete copy of this presentation is included
at the end of this report.
snip...
A comment was posted regarding bovine spongiform encephalopathy (BSE)
indicating the possible need to review the present protocol for renderers so
that carcasses which are submitted for rabies, are flagged at the render and
held until testing for rabies and BSE is completed.
snip...
PROCEEDINGS ONE HUNDRED AND SEVENTEENTH ANNUAL MEETING of the UNITED STATES
ANIMAL HEALTH ASSOCIATION Town and Country Hotel San Diego, California October
17 – 23, 2013
Friday, December 14, 2012
DEFRA U.K. What is the risk of Chronic Wasting Disease CWD being introduced
into Great Britain? A Qualitative Risk Assessment October 2012
snip...
In the USA, under the Food and Drug Administration’s BSE Feed Regulation
(21 CFR 589.2000) most material (exceptions include milk, tallow, and gelatin)
from deer and elk is prohibited for use in feed for ruminant animals. With
regards to feed for non-ruminant animals, under FDA law, CWD positive deer may
not be used for any animal feed or feed ingredients. For elk and deer considered
at high risk for CWD, the FDA recommends that these animals do not enter the
animal feed system. However, this recommendation is guidance and not a
requirement by law.
Animals considered at high risk for CWD include:
1) animals from areas declared to be endemic for CWD and/or to be CWD
eradication zones and
2) deer and elk that at some time during the 60-month period prior to
slaughter were in a captive herd that contained a CWD-positive animal.
Therefore, in the USA, materials from cervids other than CWD positive
animals may be used in animal feed and feed ingredients for non-ruminants.
The amount of animal PAP that is of deer and/or elk origin imported from
the USA to GB can not be determined, however, as it is not specified in TRACES.
It may constitute a small percentage of the 8412 kilos of non-fish origin
processed animal proteins that were imported from US into GB in 2011.
*** Overall, therefore, it is considered there is a __greater than
negligible risk___ that (nonruminant) animal feed and pet food containing deer
and/or elk protein is imported into GB.
There is uncertainty associated with this estimate given the lack of data
on the amount of deer and/or elk protein possibly being imported in these
products.
snip...
36% in 2007 (Almberg et al., 2011). In such areas, population declines of
deer of up to 30 to 50% have been observed (Almberg et al., 2011). In areas of
Colorado, the prevalence can be as high as 30% (EFSA, 2011).
The clinical signs of CWD in affected adults are weight loss and
behavioural changes that can span weeks or months (Williams, 2005). In addition,
signs might include excessive salivation, behavioural alterations including a
fixed stare and changes in interaction with other animals in the herd, and an
altered stance (Williams, 2005). These signs are indistinguishable from cervids
experimentally infected with bovine spongiform encephalopathy (BSE).
Given this, if CWD was to be introduced into countries with BSE such as GB,
for example, infected deer populations would need to be tested to differentiate
if they were infected with CWD or BSE to minimise the risk of BSE entering the
human food-chain via affected venison.
snip...
The rate of transmission of CWD has been reported to be as high as 30% and
can approach 100% among captive animals in endemic areas (Safar et al., 2008).
snip...
In summary, in endemic areas, there is a medium probability that the soil
and surrounding environment is contaminated with CWD prions and in a
bioavailable form. In rural areas where CWD has not been reported and deer are
present, there is a greater than negligible risk the soil is contaminated with
CWD prion.
snip...
In summary, given the volume of tourists, hunters and servicemen moving
between GB and North America, *** the probability of at least one person
travelling to/from a CWD affected area and, in doing so, contaminating their
clothing, footwear and/or equipment prior to arriving in GB is greater than
negligible. For deer hunters, specifically, the risk is likely to be greater
given the increased contact with deer and their environment. However, there is
significant uncertainty associated with these estimates.
snip...
Therefore, it is considered that farmed and park deer may have a higher
probability of exposure to CWD transferred to the environment than wild deer
given the restricted habitat range and higher frequency of contact with tourists
and returning GB residents.
snip...
>>>With regards to feed for non-ruminant animals, under FDA law,
CWD positive deer may not be used for any animal feed or feed ingredients. For
elk and deer considered at high risk for CWD, the FDA recommends that these
animals do not enter the animal feed system. However, this recommendation is
guidance and not a requirement by law. <<<
Draft Guidance on Use of Material From Deer and Elk in Animal Feed; CVM
Updates on Deer and Elk Withdrawn FDA Veterinarian Newsletter July/August 2003
Volume XVIII, No 4
FDA has announced the availability of a draft guidance for industry
entitled “Use of Material from Deer and Elk in Animal Feed.” This draft guidance
document (GFI #158), when finalized, will describe FDA’s current thinking
regarding the use in animal feed of material from deer and elk that are positive
for Chronic Wasting Disease (CWD) or that are at high risk for CWD.
CWD is a neurological (brain) disease of farmed and wild deer and elk that
belong in the cervidae animal family (cervids). Only deer and elk are known to
be susceptible to CWD by natural transmission. The disease has been found in
farmed and wild mule deer, white-tailed deer, North American elk, and farmed
black-tailed deer. CWD belongs to a family of animal and human diseases called
transmissible spongiform encephalopathies (TSEs). TSEs are very rare, but are
always fatal.
This draft Level 1 guidance, when finalized, will represent the Agency’s
current thinking on the topic. It does not create or confer any rights for or on
any person and does not operate to bind FDA or the public. An alternate method
may be used as long as it satisfies the requirements of applicable statutes and
regulations.
Draft guidance #158 is posted on the FDA/Center for Veterinary Medicine
Home Page. Single copies of the draft guidance may be obtained from the FDA
Veterinarian.
- - Page Last Updated: 04/16/2013
CONTAINS NON-BINDING RECOMMENDATIONS
158
Guidance for Industry
Use of Material from Deer and Elk in Animal Feed
Comments and suggestions regarding the document should be submitted to
Division of Dockets Management (HFA-305), Food and Drug Administration, 5630
Fishers Lane, Rm. 1061, Rockville, MD 20852. Submit electronic comments to
http://www.regulations.gov. All comments
should be identified with the Docket No. 03D-0186.
For questions regarding this guidance, contact Burt Pritchett, Center for
Veterinary Medicine (HFV- 222), Food and Drug Administration, 7519 Standish
Place, Rockville, MD 20855, 240-453-6860, E-mail: burt.pritchett@fda.hhs.gov.
Additional copies of this guidance document may be requested from the
Communications Staff (HFV-12), Center for Veterinary Medicine, Food and Drug
Administration, 7519 Standish Place, Rockville, MD 20855, and may be viewed on
the Internet at
http://www.fda.gov/AnimalVeterinary/GuidanceComplianceEnforcement/GuidanceforIndustry/default.htm.
U.S. Department of Health and Human Services
Food and Drug Administration Center for Veterinary Medicine September 15,
2003
CONTAINS NON-BINDING RECOMMENDATIONS
158
Guidance for Industry1
Use of Material from Deer and Elk in Animal Feed
This guidance represents the Food and Drug Administration’s current
thinking on the use of material from deer and elk in animal feed. It does not
create or confer any rights for or on any person and does not operate to bind
FDA or the public. You can use an alternative approach if the approach satisfies
the requirements of applicable statutes or regulations. If you want to discuss
an alternative approach, contact the FDA staff responsible for implementing this
guidance. If you cannot identify the appropriate FDA staff, call the appropriate
number listed on the title page of this guidance.
I. Introduction
FDA’s guidance documents, including this guidance, do not establish legally
enforceable responsibilities. Instead, guidances describe the Agency’s current
thinking on a topic and should be viewed only as recommendations, unless
specific regulatory or statutory requirements are cited. The use of the word
“should” in Agency guidances means that something is suggested or recommended,
but not required.
Under FDA’s BSE feed regulation (21 CFR 589.2000) most material from deer
and elk is prohibited for use in feed for ruminant animals. This guidance
document describes FDA’s recommendations regarding the use in all animal feed of
all material from deer and elk that are positive for Chronic Wasting Disease
(CWD) or are considered at high risk for CWD. The potential risks from CWD to
humans or non-cervid animals such as poultry and swine are not well understood.
However, because of recent recognition that CWD is spreading rapidly in
white-tailed deer, and because CWD’s route of transmission is poorly understood,
FDA is making recommendations regarding the use in animal feed of rendered
materials from deer and elk that are CWD-positive or that are at high risk for
CWD.
II. Background
CWD is a neurological (brain) disease of farmed and wild deer and elk that
belong in the animal family cervidae (cervids). Only deer and elk are known to
be susceptible to CWD by natural transmission. The disease has been found in
farmed and wild mule deer,
1 This guidance has been prepared by the Division of Animal Feeds in the
Center for Veterinary Medicine (CVM) at the Food and Drug Administration.
1
CONTAINS NON-BINDING RECOMMENDATIONS
2
white-tailed deer, North American elk, and in farmed black-tailed deer. CWD
belongs to a family of animal and human diseases called transmissible spongiform
encephalopathies (TSEs). These include bovine spongiform encephalopathy (BSE or
“mad cow” disease) in cattle; scrapie in sheep and goats; and classical and
variant Creutzfeldt-Jakob diseases (CJD and vCJD) in humans. There is no known
treatment for these diseases, and there is no vaccine to prevent them. In
addition, although validated postmortem diagnostic tests are available, there
are no validated diagnostic tests for CWD that can be used to test for the
disease in live animals.
III.
Use in animal feed of material from CWD-positive deer and elk
Material from CWD-positive animals may not be used in any animal feed or
feed ingredients. Pursuant to Sec. 402(a)(5) of the Federal Food, Drug, and
Cosmetic Act, animal feed and feed ingredients containing material from a
CWD-positive animal would be considered adulterated. FDA recommends that any
such adulterated feed or feed ingredients be recalled or otherwise removed from
the marketplace.
IV.
Use in animal feed of material from deer and elk considered at high risk
for CWD
Deer and elk considered at high risk for CWD include: (1) animals from
areas declared by State officials to be endemic for CWD and/or to be CWD
eradication zones; and (2) deer and elk that at some time during the 60-month
period immediately before the time of slaughter were in a captive herd that
contained a CWD-positive animal.
FDA recommends that materials from deer and elk considered at high risk for
CWD no longer be entered into the animal feed system. Under present
circumstances, FDA is not recommending that feed made from deer and elk from a
non-endemic area be recalled if a State later declares the area endemic for CWD
or a CWD eradication zone. In addition, at this time, FDA is not recommending
that feed made from deer and elk believed to be from a captive herd that
contained no CWD-positive animals be recalled if that herd is subsequently found
to contain a CWD-positive animal. V. Use in animal feed of material from deer
and elk NOT considered at high risk for CWD
FDA continues to consider materials from deer and elk NOT considered at
high risk for CWD to be acceptable for use in NON-RUMINANT animal feeds in
accordance with current agency regulations, 21 CFR 589.2000. Deer and elk not
considered at high risk include: (1) deer and elk from areas not declared by
State officials to be endemic for CWD and/or to be CWD eradication zones; and
(2) deer and elk that were not at some time during the 60-month period
immediately before the time of slaughter in a captive herd that contained a
CWD-positive animal.
that voluntary mad cow feed ban that became law, how did that work out for
us $
ENFORCEMENT REPORT FOR AUGUST 2, 2006
please note, considering .005 grams is lethal, I do not know how much of
this 125 TONS of banned mad cow protein was part of the ;
e) "Big Jim's" BBB Deer Ration, Big Buck Blend, Recall # V-104-6;
bbbut, this was about 10 years post mad cow feed ban from 1997. 10 years
later, and still feeding banned mad cow protein to cervids???
considering that .005 gram is lethal to several bovines, and we know that
the oral consumption of CWD tainted products is very efficient mode of
transmission of CWD.
Subject: MAD COW FEED RECALL AL AND FL VOLUME OF PRODUCT IN COMMERCE 125
TONS Products manufactured from 02/01/2005 until 06/06/2006
Date: August 6, 2006 at 6:16 pm PST
PRODUCT
a) CO-OP 32% Sinking Catfish, Recall # V-100-6;
b) Performance Sheep Pell W/Decox/A/N, medicated, net wt. 50 lbs, Recall #
V-101-6;
c) Pro 40% Swine Conc Meal -- 50 lb, Recall # V-102-6;
d) CO-OP 32% Sinking Catfish Food Medicated, Recall # V-103-6;
***e) "Big Jim's" BBB Deer Ration, Big Buck Blend, Recall # V-104-6;
f) CO-OP 40% Hog Supplement Medicated Pelleted, Tylosin 100 grams/ton, 50
lb. bag, Recall # V-105-6;
g) Pig Starter Pell II, 18% W/MCDX Medicated 282020, Carbadox -- 0.0055%,
Recall # V-106-6;
h) CO-OP STARTER-GROWER CRUMBLES, Complete Feed for Chickens from Hatch to
20 Weeks, Medicated, Bacitracin Methylene Disalicylate, 25 and 50 Lbs, Recall #
V-107-6;
i) CO-OP LAYING PELLETS, Complete Feed for Laying Chickens, Recall # 108-6;
j) CO-OP LAYING CRUMBLES, Recall # V-109-6;
k) CO-OP QUAIL FLIGHT CONDITIONER MEDICATED, net wt 50 Lbs, Recall #
V-110-6;
l) CO-OP QUAIL STARTER MEDICATED, Net Wt. 50 Lbs, Recall # V-111-6;
m) CO-OP QUAIL GROWER MEDICATED, 50 Lbs, Recall # V-112-6
CODE
Product manufactured from 02/01/2005 until 06/06/2006
RECALLING FIRM/MANUFACTURER
Alabama Farmers Cooperative, Inc., Decatur, AL, by telephone, fax, email
and visit on June 9, 2006. FDA initiated recall is complete.
REASON
Animal and fish feeds which were possibly contaminated with ruminant based
protein not labeled as "Do not feed to ruminants".
VOLUME OF PRODUCT IN COMMERCE
125 tons
DISTRIBUTION
AL and FL
END OF ENFORCEMENT REPORT FOR AUGUST 2, 2006
###
Rangen, Inc,
10,000,000+ LBS. of PROHIBITED BANNED MAD COW FEED I.E. BLOOD LACED MBM IN
COMMERCE USA 2007
Date: March 21, 2007 at 2:27 pm PST
RECALLS AND FIELD CORRECTIONS: VETERINARY MEDICINES -- CLASS II
___________________________________
PRODUCT
Bulk cattle feed made with recalled Darling's 85% Blood Meal, Flash Dried,
Recall # V-024-2007
CODE
Cattle feed delivered between 01/12/2007 and 01/26/2007
RECALLING FIRM/MANUFACTURER
Pfeiffer, Arno, Inc, Greenbush, WI. by conversation on February 5, 2007.
Firm initiated recall is ongoing.
REASON
Blood meal used to make cattle feed was recalled because it was cross-
contaminated with prohibited bovine meat and bone meal that had been
manufactured on common equipment and labeling did not bear cautionary BSE
statement.
VOLUME OF PRODUCT IN COMMERCE
42,090 lbs.
DISTRIBUTION
WI ___________________________________
PRODUCT
Custom dairy premix products: MNM ALL PURPOSE Pellet, HILLSIDE/CDL Prot-
Buffer Meal, LEE, M.-CLOSE UP PX Pellet, HIGH DESERT/ GHC LACT Meal, TATARKA, M
CUST PROT Meal, SUNRIDGE/CDL PROTEIN Blend, LOURENZO, K PVM DAIRY Meal, DOUBLE B
DAIRY/GHC LAC Mineral, WEST PIONT/GHC CLOSEUP Mineral, WEST POINT/GHC LACT Meal,
JENKS, J/COMPASS PROTEIN Meal, COPPINI - 8# SPECIAL DAIRY Mix, GULICK, L-LACT
Meal (Bulk), TRIPLE J - PROTEIN/LACTATION, ROCK CREEK/GHC MILK Mineral,
BETTENCOURT/GHC S.SIDE MK-MN, BETTENCOURT #1/GHC MILK MINR, V&C DAIRY/GHC
LACT Meal, VEENSTRA, F/GHC LACT Meal, SMUTNY, A- BYPASS ML W/SMARTA, Recall #
V-025-2007
CODE
The firm does not utilize a code - only shipping documentation with
commodity and weights identified.
RECALLING FIRM/MANUFACTURER
Rangen, Inc, Buhl, ID, by letters on February 13 and 14, 2007. Firm
initiated recall is complete.
REASON
Products manufactured from bulk feed containing blood meal that was cross
contaminated with prohibited meat and bone meal and the labeling did not bear
cautionary BSE statement.
VOLUME OF PRODUCT IN COMMERCE
9,997,976 lbs.
DISTRIBUTION
ID and NV
END OF ENFORCEMENT REPORT FOR MARCH 21, 2007
-------- Original Message --------
Subject: DOCKET-- 03D-0186 -- FDA Issues Draft Guidance on Use of Material
From Deer and Elk in Animal Feed; Availability
Date: Fri, 16 May 2003 11:47:37 –0500
From: "Terry S. Singeltary Sr."
To: fdadockets@oc.fda.gov
Greetings FDA,
i would kindly like to comment on; Docket 03D-0186FDA Issues Draft Guidance
on Use of Material From Deer and Elk in Animal Feed; Availability Several
factors on this apparent voluntary proposal disturbs me greatly, please allow me
to point them out;
snip...
Oral transmission and early lymphoid tropism of chronic wasting
diseasePrPres in mule deer fawns (Odocoileus hemionus ) These results indicate
that CWD PrP res can be detected in lymphoid tissues draining the alimentary
tract within a few weeks after oral exposure to infectious prions and may
reflect the initial pathway of CWD infection in deer. The rapid infection of
deer fawns following exposure by the most plausible natural route is consistent
with the efficient horizontal transmission of CWD in nature and enables
accelerated studies of transmission and pathogenesis in the native
species.
snip...
now, just what is in that deer feed? _ANIMAL PROTEIN_
Subject: MAD DEER/ELK DISEASE AND POTENTIAL SOURCES
Date: Sat, 25 May 2002 18:41:46 -0700 From: "Terry S. Singeltary Sr."
Reply-To: BSE-LTo: BSE-L
8420-20.5% Antler DeveloperFor Deer and Game in the wildGuaranteed Analysis
Ingredients / Products Feeding Directions
snip...
_animal protein_
snip...
DEPARTMENT OF HEALTH & HUMAN SERVICESPUBLIC HEALTH SERVICEFOOD AND DRUG
ADMINISTRATIONApril 9, 2001 WARNING LETTER01-PHI-12CERTIFIED MAILRETURN RECEIPT
REQUESTED
Brian J. Raymond, Owner Sandy Lake Mills 26 Mill Street P.O. Box 117 Sandy
Lake, PA 16145
PHILADELPHIA DISTRICT
Tel: 215-597-4390
Dear Mr. Raymond:Food and Drug Administration Investigator Gregory E.
Beichner conducted an inspection of your animal feed manufacturing operation,
located in Sandy Lake, Pennsylvania, on March 23,2001, and determined that your
firm manufactures animal feeds including feeds containing prohibited materials.
The inspection found significant deviations from the requirements set forth in
Title 21, code of Federal Regulations, part 589.2000 - Animal Proteins
Prohibited in Ruminant Feed. The regulation is intended to prevent the
establishment and amplification of Bovine Spongiform Encephalopathy (BSE) . Such
deviations cause products being manufactured at this facility to be misbranded
within the meaning of Section 403(f), of the Federal Food, Drug, and Cosmetic
Act (the Act).Our investigation found failure to label your swine feed with the
required cautionary statement "Do Not Feed to cattleor other Ruminants" The FDA
suggests that the statement be distinguished by different type-size or color or
other means of highlighting the statement so that it is easily noticed by a
purchaser.
In addition, we note that you are using approximately 140 pounds of cracked
corn to flush your mixer used in the manufacture of animal feeds containing
prohibited material. This flushed material is fed to wild game including deer, a
ruminant animal.Feed material which may potentially contain prohibited material
should not be fed to ruminant animals which may become part of the food
chain.The above is not intended to be an all-inclusive list of deviations
fromthe regulations. As a manufacturer of materials intended for animalfeed use,
you are responsible for assuring that your overall operation and the products
you manufacture and distribute are in compliance withthe law. We have enclosed a
copy of FDA's Small Entity Compliance Guideto assist you with complying with the
regulation...
snip...end...full text ;
2003D-0186 Guidance for Industry: Use of Material From Deer and Elk In
Animal Feed
EMC 1 Terry S. Singeltary Sr. Vol #: 1
see my full text submission here ;
Sunday, December 15, 2013
FDA PART 589 -- SUBSTANCES PROHIBITED FROM USE IN ANIMAL FOOD OR FEED
VIOLATIONS OFFICIAL ACTION INDICATED OIA UPDATE DECEMBER 2013 UPDATE
*** Infectious agent of sheep scrapie may persist in the environment for at
least 16 years***
Gudmundur Georgsson1, Sigurdur Sigurdarson2 and Paul Brown3
New studies on the heat resistance of hamster-adapted scrapie agent:
Threshold survival after ashing at 600°C suggests an inorganic template of
replication
Prion Infected Meat-and-Bone Meal Is Still Infectious after Biodiesel
Production
Detection of protease-resistant cervid prion protein in water from a
CWD-endemic area
A Quantitative Assessment of the Amount of Prion Diverted to Category 1
Materials and Wastewater During Processing
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
PPo4-4: Survival and Limited Spread of TSE Infectivity after Burial
Comment from Terry Singeltary.
This is a Comment on the Animal and Plant Health Inspection Service (APHIS)
Notice: Program Standards:
Chronic Wasting Disease Herd Certification Program and Interstate Movement
of Farmed or Captive Deer, Elk, and Moose
>>>The CWD herd certification program is a voluntary, cooperative
program that establishes minimum requirements for the interstate movement of
farmed or captive cervids, provisions for participating States to administer
Approved State CWD Herd Certification Programs, and provisions for participating
herds to become certified as having a low risk of being infected with
CWD<<<
Greetings USDA/APHIS et al,
I kindly would like to comment on Docket No. 00-108-10 Chronic Wasting
Disease Herd Certification Program and Interstate Movement of Farmed or Captive
Deer, Elk, and Moose; Program Standards.
I believe, and in my opinion, and this has been proven by scientific facts,
that without a validated and certified test for chronic wasting disease cwd,
that is 100% sensitive, and in use, any voluntary effort will be futile. the
voluntary ban on mad cow feed and SRMs have failed terribly, the bse mad cow
surveillance program has failed terribly, as well as the testing for bse tse
prion in cattle, this too has failed terrible. all this has been proven time and
time again via OIG reports and GOA reports.
I believe that until this happens, 100% cwd testing with validated test,
ALL MOVEMENT OF CERVIDS BETWEEN STATES MUST BE BANNED, AND THE BORDERS CLOSED TO
INTERSTATE MOVEMENT OF CERVIDS. there is simply to much at risk.
In my opinion, and the opinions of many scientists and DNR officials, that
these so called game farms are the cause of the spreading of chronic wasting
disease cwd through much negligence. the game farms in my opinion are not the
only cause, but a big factor. I kindly wish to submit the following to show what
these factors are, and why interstate movement of cervids must be banned.
snip...see full text ;
See attached file(s)
Singeltary submission ;
Program Standards: Chronic Wasting Disease Herd Certification Program and
Interstate Movement of Farmed or Captive Deer, Elk, and Moose
*** DOCUMENT ID: APHIS-2006-0118-0411
*** 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.
New studies on the heat resistance of hamster-adapted scrapie agent:
Threshold survival after ashing at 600°C suggests an inorganic template of
replication
Prion Infected Meat-and-Bone Meal Is Still Infectious after Biodiesel
Production
Detection of protease-resistant cervid prion protein in water from a
CWD-endemic area
A Quantitative Assessment of the Amount of Prion Diverted to Category 1
Materials and Wastewater During Processing
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
PPo4-4:
Survival and Limited Spread of TSE Infectivity after Burial
PPo4-4:
Survival and Limited Spread of TSE Infectivity after Burial
Karen Fernie, Allister Smith and Robert A. Somerville The Roslin Institute
and R(D)SVS; University of Edinburgh; Roslin, Scotland UK
Scrapie and chronic wasting disease probably spread via environmental
routes, and there are also concerns about BSE infection remaining in the
environment after carcass burial or waste 3disposal. In two demonstration
experiments we are determining survival and migration of TSE infectivity when
buried for up to five years, as an uncontained point source or within bovine
heads. Firstly boluses of TSE infected mouse brain were buried in lysimeters
containing either sandy or clay soil. Migration from the boluses is being
assessed from soil cores taken over time. With the exception of a very small
amount of infectivity found 25 cm from the bolus in sandy soil after 12 months,
no other infectivity has been detected up to three years. Secondly, ten bovine
heads were spiked with TSE infected mouse brain and buried in the two soil
types. Pairs of heads have been exhumed annually and assessed for infectivity
within and around them. After one year and after two years, infectivity was
detected in most intracranial samples and in some of the soil samples taken from
immediately surrounding the heads. The infectivity assays for the samples in and
around the heads exhumed at years three and four are underway. These data show
that TSE infectivity can survive burial for long periods but migrates slowly.
Risk assessments should take into account the likely long survival rate when
infected material has been buried.
The authors gratefully acknowledge funding from DEFRA.
*** Spraker suggested an interesting explanation for the occurrence of CWD.
The deer pens at the Foot Hills Campus were built some 30-40 years ago by a Dr.
Bob Davis. At or abut that time, allegedly, some scrapie work was conducted at
this site. When deer were introduced to the pens they occupied ground that had
previously been occupied by sheep.
now, decades later ;
2012
PO-039: A comparison of scrapie and chronic wasting disease in white-tailed
deer
snip...
After a natural route of exposure, 100% of WTD were susceptible to scrapie.
Deer developed clinical signs of wasting and mental depression and were
necropsied from 28 to 33 months PI. Tissues from these deer were positive for
PrPSc by IHC and WB. Similar to IC inoculated deer, samples from these deer
exhibited two different molecular profiles: samples from obex resembled CWD
whereas those from cerebrum were similar to the original scrapie inoculum. On
further examination by WB using a panel of antibodies, the tissues from deer
with scrapie exhibit properties differing from tissues either from sheep with
scrapie or WTD with CWD. Samples from WTD with CWD or sheep with scrapie are
strongly immunoreactive when probed with mAb P4, however, samples from WTD with
scrapie are only weakly immunoreactive. In contrast, when probed with mAb’s 6H4
or SAF 84, samples from sheep with scrapie and WTD with CWD are weakly
immunoreactive and samples from WTD with scrapie are strongly positive. This
work demonstrates that WTD are highly susceptible to sheep scrapie, but on first
passage, scrapie in WTD is differentiable from CWD.
2011
*** After a natural route of exposure, 100% of white-tailed deer were
susceptible to scrapie.
see ;
Scrapie in Deer: Comparisons and Contrasts to Chronic Wasting Disease
(CWD)
Justin J. Greenlee of the Virus and Prion Diseases Research Unit, National
Animal Disease Center, ARS, USDA, Ames, IA provided a presentation on scrapie
and CWD in inoculated deer.
Interspecies transmission studies afford the opportunity to better
understand the potential host range and origins of prion diseases. We inoculated
white-tailed deer intracranially (IC) and by a natural route of exposure
(concurrent oral and intranasal inoculation) with a US scrapie isolate. All deer
inoculated by the intracranial route had evidence of PrPSc accumulation and
those necropsied after 20 months post-inoculation (PI) (3/5) had clinical signs,
spongiform encephalopathy, and widespread distribution of PrPSc in neural and
lymphoid tissues. A single deer that was necropsied at 15.6 months PI did not
have clinical signs, but had widespread distribution of PrPSc. This highlights
the facts that 1) prior to the onset of clinical signs PrPSc is widely
distributed in the CNS and lymphoid tissues and 2) currently used diagnostic
methods are sufficient to detect PrPSc prior to the onset of clinical signs. The
results of this study suggest that there are many similarities in the
manifestation of CWD and scrapie in white-tailed deer after IC inoculation
including early and widespread presence of PrPSc in lymphoid tissues, clinical
signs of depression and weight loss progressing to wasting, and an incubation
time of 21-23 months. Moreover, western blots (WB) done on brain material from
the obex region have a molecular profile consistent with CWD and distinct from
tissues of the cerebrum or the scrapie inoculum. However, results of microscopic
and IHC examination indicate that there are differences between the lesions
expected in CWD and those that occur in deer with scrapie: amyloid plaques were
not noted in any sections of brain examined from these deer and the pattern of
immunoreactivity by IHC was diffuse rather than plaque-like. After a natural
route of exposure, 100% of white-tailed deer were susceptible to scrapie. Deer
developed clinical signs of wasting and mental depression and were necropsied
from 28 to 33 months PI. Tissues from these deer were positive for scrapie by
IHC and WB. Tissues with PrPSc immunoreactivity included brain, tonsil,
retropharyngeal and mesenteric lymph nodes, hemal node, Peyer’s patches, and
spleen. While two WB patterns have been detected in brain regions of deer
inoculated by the natural route, unlike the IC inoculated deer, the pattern
similar to the scrapie inoculum predominates.
Scrapie in Deer: Comparisons and Contrasts to Chronic Wasting Disease (CWD)
Justin J. Greenlee of the Virus and Prion Diseases Research Unit, National
Animal Disease Center, ARS, USDA, Ames, IA provided a presentation on scrapie
and CWD in inoculated deer. Interspecies transmission studies afford the
opportunity
After a natural route of exposure, 100% of white-tailed deer were
susceptible to scrapie. Deer developed clinical signs of wasting and mental
depression and were necropsied from 28 to 33 months PI. Tissues from these deer
were positive for scrapie by IHC and WB. Tissues with PrPSc immunoreactivity
included brain, tonsil, retropharyngeal and mesenteric lymph nodes, hemal node,
Peyer’s patches, and spleen. While two WB patterns have been detected in brain
regions of deer inoculated by the natural route, unlike the IC inoculated deer,
the pattern similar to the scrapie inoculum predominates.
2011 Annual Report
Research Project: TRANSMISSION, DIFFERENTIATION, AND PATHOBIOLOGY OF
TRANSMISSIBLE SPONGIFORM ENCEPHALOPATHIES Location: Virus and Prion Research
Unit 2011 Annual Report
In Objective 1, Assess cross-species transmissibility of transmissible
spongiform encephalopathies (TSEs) in livestock and wildlife, numerous
experiments assessing the susceptibility of various TSEs in different host
species were conducted. Most notable is deer inoculated with scrapie, which
exhibits similarities to chronic wasting disease (CWD) in deer suggestive of
sheep scrapie as an origin of CWD.
snip...
4. Accomplishments
1. Deer inoculated with domestic isolates of sheep scrapie.
Scrapie-affected deer exhibit 2 different patterns of disease associated prion
protein. In some regions of the brain the pattern is much like that observed for
scrapie, while in others it is more like chronic wasting disease (CWD), the
transmissible spongiform encephalopathy typically associated with deer. This
work conducted by ARS scientists at the National Animal Disease Center, Ames, IA
suggests that an interspecies transmission of sheep scrapie to deer may have
been the origin of CWD. This is important for husbandry practices with both
captive deer, elk and sheep for farmers and ranchers attempting to keep their
herds and flocks free of CWD and scrapie.
White-tailed Deer are Susceptible to Scrapie by Natural Route of Infection
snip...
This work demonstrates for the first time that white-tailed deer are
susceptible to sheep scrapie by potential natural routes of inoculation.
In-depth analysis of tissues will be done to determine similarities between
scrapie in deer after intracranial and oral/intranasal inoculation and chronic
wasting disease resulting from similar routes of inoculation.
see full text ;
AD.63:
Susceptibility of domestic cats to chronic wasting disease
Amy V.Nalls,1 Candace Mathiason,1 Davis Seelig,2 Susan Kraft,1 Kevin
Carnes,1 Kelly Anderson,1 Jeanette Hayes-Klug1 and Edward A. Hoover1 1Colorado
State University; Fort Collins, CO USA; 2University of Minnesota; Saint Paul, MN
USA
Domestic and nondomestic cats have been shown to be susceptible to feline
spongiform encephalopathy (FSE), almost certainly caused by consumption of
bovine spongiform encephalopathy (BSE)-contaminated meat. Because domestic and
free-ranging nondomestic felids scavenge cervid carcasses, including those in
areas affected by chronic wasting disease (CWD), we evaluated the susceptibility
of the domestic cat (Felis catus) to CWD infection experimentally. Cohorts of 5
cats each were inoculated either intracerebrally (IC) or orally (PO) with
CWD-infected deer brain. At 40 and 42 mo post-inoculation, two IC-inoculated
cats developed signs consistent with prion disease, including a stilted gait,
weight loss, anorexia, polydipsia, patterned motor behaviors, head and tail
tremors, and ataxia, and progressed to terminal disease within 5 mo. Brains from
these two cats were pooled and inoculated into cohorts of cats by IC, PO, and
intraperitoneal and subcutaneous (IP/SC) routes. Upon subpassage, feline-adapted
CWD (FelCWD) was transmitted to all IC-inoculated cats with a decreased
incubation period of 23 to 27 mo. FelCWD was detected in the brains of all the
symptomatic cats by western blotting and immunohistochemistry and abnormalities
were seen in magnetic resonance imaging, including multifocal T2 fluid
attenuated inversion recovery (FLAIR) signal hyper-intensities, ventricular size
increases, prominent sulci, and white matter tract cavitation. Currently, 3 of 4
IP/SQ and 2 of 4 PO inoculared cats have developed abnormal behavior patterns
consistent with the early stage of feline CWD.
*** These results demonstrate that CWD can be transmitted and adapted to
the domestic cat, thus raising the issue of potential cervid-to- feline
transmission in nature.
PO-081: Chronic wasting disease in the cat— Similarities to feline
spongiform encephalopathy (FSE)
FELINE SPONGIFORM ENCEPHALOPATHY FSE
Chronic Wasting Disease Susceptibility of Four North American Rodents
Chad J. Johnson1*, Jay R. Schneider2, Christopher J. Johnson2, Natalie A.
Mickelsen2, Julia A. Langenberg3, Philip N. Bochsler4, Delwyn P. Keane4, Daniel
J. Barr4, and Dennis M. Heisey2 1University of Wisconsin School of Veterinary
Medicine, Department of Comparative Biosciences, 1656 Linden Drive, Madison WI
53706, USA 2US Geological Survey, National Wildlife Health Center, 6006
Schroeder Road, Madison WI 53711, USA 3Wisconsin Department of Natural
Resources, 101 South Webster Street, Madison WI 53703, USA 4Wisconsin Veterinary
Diagnostic Lab, 445 Easterday Lane, Madison WI 53706, USA *Corresponding author
email: cjohnson@svm.vetmed.wisc.edu
We intracerebrally challenged four species of native North American rodents
that inhabit locations undergoing cervid chronic wasting disease (CWD)
epidemics. The species were: deer mice (Peromyscus maniculatus), white-footed
mice (P. leucopus), meadow voles (Microtus pennsylvanicus), and red-backed voles
(Myodes gapperi). The inocula were prepared from the brains of hunter-harvested
white-tailed deer from Wisconsin that tested positive for CWD. Meadow voles
proved to be most susceptible, with a median incubation period of 272 days.
Immunoblotting and immunohistochemistry confirmed the presence of PrPd in the
brains of all challenged meadow voles. Subsequent passages in meadow voles lead
to a significant reduction in incubation period. The disease progression in
red-backed voles, which are very closely related to the European bank vole (M.
glareolus) which have been demonstrated to be sensitive to a number of TSEs, was
slower than in meadow voles with a median incubation period of 351 days. We
sequenced the meadow vole and red-backed vole Prnp genes and found three amino
acid (AA) differences outside of the signal and GPI anchor sequences. Of these
differences (T56-, G90S, S170N; read-backed vole:meadow vole), S170N is
particularly intriguing due its postulated involvement in "rigid loop" structure
and CWD susceptibility. Deer mice did not exhibit disease signs until nearly 1.5
years post-inoculation, but appear to be exhibiting a high degree of disease
penetrance. White-footed mice have an even longer incubation period but are also
showing high penetrance. Second passage experiments show significant shortening
of incubation periods. Meadow voles in particular appear to be interesting lab
models for CWD. These rodents scavenge carrion, and are an important food source
for many predator species. Furthermore, these rodents enter human and domestic
livestock food chains by accidental inclusion in grain and forage. Further
investigation of these species as potential hosts, bridge species, and
reservoirs of CWD is required.
please see ;
UPDATED CORRESPONDENCE FROM AUTHORS OF THIS STUDY I.E. COLBY, PRUSINER ET
AL, ABOUT MY CONCERNS OF THE DISCREPANCY BETWEEN THEIR FIGURES AND MY FIGURES OF
THE STUDIES ON CWD TRANSMISSION TO CATTLE ;
----- Original Message -----
From: David Colby To: flounder9@verizon.net
Cc: stanley@XXXXXXXX
Sent: Tuesday, March 01, 2011 8:25 AM
Subject: Re: FW: re-Prions David W. Colby1,* and Stanley B. Prusiner1,2 +
Author Affiliations
Dear Terry Singeltary,
Thank you for your correspondence regarding the review article Stanley
Prusiner and I recently wrote for Cold Spring Harbor Perspectives. Dr. Prusiner
asked that I reply to your message due to his busy schedule. We agree that the
transmission of CWD prions to beef livestock would be a troubling development
and assessing that risk is important. In our article, we cite a peer-reviewed
publication reporting confirmed cases of laboratory transmission based on
stringent criteria. The less stringent criteria for transmission described in
the abstract you refer to lead to the discrepancy between your numbers and ours
and thus the interpretation of the transmission rate. We stand by our assessment
of the literature--namely that the transmission rate of CWD to bovines appears
relatively low, but we recognize that even a low transmission rate could have
important implications for public health and we thank you for bringing attention
to this matter. Warm Regards, David Colby -- David Colby, PhDAssistant Professor
Department of Chemical Engineering University of Delaware
===========END...TSS==============
> First transmission of CWD to transgenic mice over-expressing bovine
prion protein gene (TgSB3985)
PRION 2014 - PRIONS: EPIGENETICS and NEURODEGENERATIVE DISEASES – Shaping
up the future of prion research
Animal TSE Workshop 10.40 – 11.05 Talk Dr. L. Cervenakova First
transmission of CWD to transgenic mice over-expressing bovine prion protein gene
(TgSB3985)
Thursday, November 21, 2013
*** Assessing the susceptibility of transgenic mice over-expressing deer
prion protein to bovine spongiform encephalopathy
The present study was designed to assess the susceptibility of the
prototypic mouse line, Tg(CerPrP)1536+/- to bovine spongiform encephalopathy
(BSE) prions, which have the ability to overcome species barriers.
Tg(CerPrP)1536+/- mice challenged with red deer-adapted BSE resulted in a
90-100% attack rates, BSE from cattle failed to transmit, indicating agent
adaptation in the deer.
P.126: Successful transmission of chronic wasting disease (CWD) into mice
over-expressing bovine prion protein (TgSB3985)
Larisa Cervenakova,1 Christina J Sigurdson,2 Pedro Piccardo,3 Oksana
Yakovleva,1 Irina Vasilyeva,1 Jorge de Castro,1 Paula Saá,1 and Anton Cervenak1
1American Red Cross, Holland Laboratory; Rockville, MD USA; 2University of
California; San Diego, CA USA; 3Lab TSE/OBRR /CBER/FDA; Rockville, MD USA
Keywords: chronic wasting disease, transmission, transgenic mouse, bovine
prion protein
Background. CWD is a disease affecting wild and farmraised cervids in North
America. Epidemiological studies provide no evidence of CWD transmission to
humans. Multiple attempts have failed to infect transgenic mice expressing human
PRNP gene with CWD. The extremely low efficiency of PrPCWD to convert normal
human PrPC in vitro provides additional evidence that transmission of CWD to
humans cannot be easily achieved. However, a concern about the risk of CWD
transmission to humans still exists. This study aimed to establish and
characterize an experimental model of CWD in TgSB3985 mice with the following
attempt of transmission to TgHu mice.
Materials and Methods. TgSB3985 mice and wild-type FVB/ NCrl mice were
intracranially injected with 1% brain homogenate from a CWD-infected Tga20 mouse
(CWD/Tga20). TgSB3985 and TgRM (over-expressing human PrP) were similarly
injected with 5% brain homogenates from CWD-infected white-tailed deer (CWD/WTD)
or elk (CWD/Elk). Animals were observed for clinical signs of neurological
disease and were euthanized when moribund. Brains and spleens were removed from
all mice for PrPCWD detection by Western blotting (WB). A histological analysis
of brains from selected animals was performed: brains were scored for the
severity of spongiform change, astrogliosis, and PrPCWD deposition in ten brain
regions.
Results. Clinical presentation was consistent with TSE. More than 90% of
TgSB3985 and wild-type mice infected with CWD/Tga20, tested positive for PrPres
in the brain but only mice in the latter group carried PrPCWD in their spleens.
We found evidence for co-existence or divergence of two CWD/ Tga20 strains based
on biochemical and histological profiles. In TgSB3985 mice infected with CWD-elk
or CWD-WTD, no animals tested positive for PrPCWD in the brain or in the spleen
by WB. However, on neuropathological examination we found presence of amyloid
plaques that stained positive for PrPCWD in three CWD/WTD- and two
CWD/Elk-infected TgSB3985 mice. The neuropathologic profiles in CWD/WTD- and
CWD/Elkinfected mice were similar but unique as compared to profiles of BSE,
BSE-H or CWD/Tg20 agents propagated in TgSB3985 mice. None of CWD-infected TgRM
mice tested positive for PrPCWD by WB or by immunohistochemical detection.
Conclusions. To our knowledge, this is the first established experimental
model of CWD in TgSB3985. We found evidence for co-existence or divergence of
two CWD strains adapted to Tga20 mice and their replication in TgSB3985 mice.
Finally, we observed phenotypic differences between cervid-derived CWD and
CWD/Tg20 strains upon propagation in TgSB3985 mice. Further studies are underway
to characterize these strains.
P.89: Prions survive long-term burial in soil with some groundwater
dissemination
Allister JA Smith,1 Karen Fernie,1 Ben Maddison,2 Keith Bishop,2 Kevin
Gough,3 and Robert A Somerville1 1The Roslin Institute; University of Edinburgh;
Edinburgh, UK; 2ADAS Biotechnology Group, University of Nottingham; Nottingham,
UK; 3University of Nottingham; Nottingham, UK
An intrinsic property of prions is their extreme resistance to degradation.
When they are deposited within the environment, whether from inappropriate
disposal by man or from fallen diseased livestock, there is the potential to
further propagate cases of disease for many years. It is evidenced that the
spread of scrapie in sheep and chronic wasting disease in deer have occurred in
this manner.
We mimicked such scenarios under large-scale field conditions to determine
the extent to which TSE infectivity survives or disseminates in soil and soil
water over five years. The mouse passaged BSE strain, 301V, was used to spike
buried bovine heads, or was buried as an uncontained bolus in large soil-filled
lysimeters. Two soils were examined, a free-draining sandy loam and a
water-retentive clay loam.
Infectivity, determined by bioassay in mice, was recovered from all heads
exhumed annually for 5 years from both soil types, with little reduction in the
amount of infectivity over time. Small amounts of infectivity were found in soil
samples immediately surrounding the heads but not in samples remote from them.
Commensurate with this there was no evidence of significant lateral movement of
infectivity from the bolus buried in a large soil mass. However large amounts of
infectivity were recovered at the original bolus burial site in both soils.
There was limited vertical upward movement of infectivity from the bolus buried
in clay and downward movement from the bolus buried in sand perhaps reflecting
the clay soils propensity to flood.
Throughout the course of the experiment rainwater particulate from several
lysimeters was trapped on glass-fibre filters. Extracts from these filters were
subject to serial PMCA (protein misfolding cyclic amplification) which was
optimised using 301V-spiked samples and blinded controls. All positive and
negative control samples were correctly determined. We have tested 44 samples
from rainwater passed through the clay lysimeter filters, and found 9 positive
samples, mainly from the initial 8 months of the experiment.
We conclude that TSE infectivity is likely to survive burial for long time
periods with minimal loss of infectivity and limited movement from the original
burial site. However PMCA results have shown that there is the potential for
rainwater to elute TSErelated material from soil which could lead to the
contamination of a wider area. These experiments reinforce the importance of
risk assessment when disposing of TSE risk materials.
P.121: Efficient transmission of prion disease through environmental
contamination
Sandra Pritzkow, Rodrigo Morales, and Claudio Soto Mitchell Center for
Alzheimer’s disease and related Brain disorders; University of Texas Medical
School at Houston; Hourston, TX USA
Chronic wasting disease (CWD) is a prion disorder effecting captive and
free-ranging deer and elk. The efficient propagation suggests that horizontal
transmission through contaminated environment may play an important role. It has
been shown that infectious prions enter the environment through saliva, feces,
urine, blood or placenta tissue from infected animals, as well as by carcasses
from diseased animals and can stay infectious inside soil over several
years.
82 Prion Volume 8 Supplement
We hypothesize that environmental components getting in contact with
infectious prions can also play a role for the horizontal transmission of prion
diseases. To study this issue, surfaces composed of various environmentally
relevant materials were exposed to infectious prions and the attachment and
retention of infectious material was studied in vitro and in vivo. We analyzed
polypropylene, glass, stainless steel, wood, stone, aluminum, concrete and brass
surfaces exposed to 263K-infected brain homogenate. For in vitro analyses, the
material was incubated in serial dilutions of 263K-brain homogenate, washed
thoroughly and analyzed for the presence of PrPSc by PMCA. The results show that
even highly diluted PrPSc can bind efficiently to polypropylene, stainless
steel, glass, wood and stone and propagate the conversion of normal prion
protein. For in vivo experiments, hamsters were ic injected with implants
incubated in 1% 263K-infected brain homogenate. Hamsters, inoculated with
263K-contaminated implants of all groups, developed typical signs of prion
disease, whereas control animals inoculated with non-contaminated materials did
not.
In addition, in order to study the transmission in a more natural setting,
we exposed a group of hamster to habit in the presence of spheres composed of
various materials that were pretreated with 263K prions. Many of the hamsters
exposed to these contaminated materials developed typical signs of the disease
that were confirmed by immunohistological and biochemical analyses.
These findings suggest that various surfaces can efficiently bind
infectious prions and act as carriers of infectivity, suggesting that diverse
elements in the environment may play an important role in horizontal prion
transmission.
P.138: Phenotypic diversity in meadow vole (Microtus pennsylvanicus) prion
diseases following challenge with chronic wasting disease isolates
Christopher J Johnson,1 Christina M Carlson,1,2 Jay R Schneider,1 Jamie K
Wiepz,1 Crystal L Meyerett-Reid,3 Mark D Zabel,3 Joel A Pedersen,2 and Dennis M
Heisey1 1USGS National Wildlife Health Center; Madison, WI USA; 2University of
Wisconsin— Madison; Madison, WI USA; 3Colorado State University; Fort Collins,
CO USA
Chronic wasting disease (CWD), a prion disease of cervids (deer, elk and
moose), is spreading unchecked through large sections of North America.
Transmission of CWD among cervids is especially facile and can occur through
direct animal-toanimal contact and indirectly through contact with prions shed
from infected animals. The disease transmission threat posed by CWD to other
wildlife species remains unknown, but other species are inevitably exposed to
CWD by consumption of infectious materials and through contact with
environmental CWD contamination.
In this study, we investigated the transmission and adaptation of various
white-tailed deer CWD isolates in the meadow vole (Microtus pennsylvanicus), a
native North American rodent that is sympatric with current CWD epizootics that
we have previously established is susceptible to CWD. We found that serial
subpassage of CWD from white-tailed deer homozygous for glycine at position 96
(96GG) of the prion protein in meadow voles resulted in the selection of a
single prion strain that was characterized by homogeneity in incubation period,
abnormal prion protein (PrPTSE) glycoform ratio, lesion profile and PrPTSE
deposition pattern. In contrast, passage of CWD from heterozygous 96GS genotype
deer produced four unique disease phenotypes upon first passage. Subpassage of
these types ultimately resulted in selection of a single strain by third passage
that was distinct from the 96GG genotype CWD-derived strain.
We also establish that meadow voles are susceptible to CWD via peripheral
challenge, albeit with lower attack rates and longer incubation periods.
Interestingly, oral challenge of meadow voles with CWD resulted in subclinical
infection in primary passage animals, but manifested as clinical prion disease
upon subpassage.
Our data establish that meadow voles are permissive to CWD via peripheral
exposure route, suggesting they could serve as an environmental reservoir for
CWD. Additionally, our data are consistent with the hypothesis that at least two
strains of CWD circulate in naturally-infected cervid populations and provide
evidence that meadow voles are a useful tool for CWD strain typing.
P.141: Abundant prion shedding in CWD-infected deer revealed by Realtime
conversion
Edward A Hoover,1 Davin M Henderson,1 Nathaniel D Denkers,1 Candace K
Mathiason,1 Matteo Manca,2,3 and Byron Caughey2 1Prion Research Center, Colorado
State University; Fort Collins, CO USA; 2Laboratory of Persistent Viral
Diseases, NI AID; Hamilton, MT USA; 3Department of Biomedical Sciences,
University of Cagliari; Monserrato, Italy
Background/Introduction. Chronic wasting disease (CWD) is unique among
prion diseases in its efficient lateral transmission in nature. While the
presence of infectious prions in body fluids and excreta of infected cervids has
been demonstrated by bioassay, the dynamics, magnitude, and consequences of
prion shedding remain unknown. The present studies were undertaken to determine
the kinetics, duration, and magnitude of prion shedding in infected white-tailed
deer.
Materials and Methods. Longitudinal samples were collected from
white-tailed deer over a 2-year span after either oral (n=11)] aerosol (n = 6)
CWD exposure. The assay protocol employed phosphotungstic acid precipitation of
either whole saliva or the pelleted fraction of urine to seed recombinant Syrian
hamster prion PrP substrate in RT-QuIC reactions. Prion seeding activity was
assayed in 8 replicates of each sample employing thioflavin T detection in a
96-well plate-based fluorometer. Prion seeding reaction rate was determined by
taking the inverse of the time at which samples exceeded a threshold of 5
standard deviations above the mean fluorescence of negative controls (1/time to
threshold). Seeding activity was quantitated by comparing the realtime
conversion reaction rate to a standard curve derived from a reference bioassayed
brain pool homogenate from deer with terminal CWD.
Results. We analyzed >200 longitudinally collected, blinded, then
randomized saliva and urine samples from 17 CWDinfected and 3 uninfected
white-tailed deer. We detected prion shedding as early as 3 months post exposure
and sustained thereafter throughout the disease course in both aerosol and
orally exposed deer. The incidence of non-specific false positive results from
>500 saliva and urine samples from negative control deer was 0.8%. By
comparing real-time reaction rates for these body fluids to a bioassayed
serially diluted brain control, we estimated that ≤1 ml of saliva or urine from
pre-symptomatic infected deer constitutes a lethal infectious prion dose.
Conclusion. CWD prions are shed in saliva and urine of infected deer as
early as 3 months post infection and throughout the subsequent >1.5 year
course of infection. In current work we are examining the relationship of
prionemia to excretion and the impact of excreted prion binding to surfaces and
particulates in the environment.
Acknowledgments. Support: NIH-RO1-NS-061902; Morris Animal Foundation
D12ZO-045
P.154: Urinary shedding of prions in Chronic Wasting Disease infected
white-tailed deer
Nathaniel D Denkers,1 Davin M Henderson, 1 Candace K Mathiason,1 and Edward
A Hoover1 1Prion Research Center, Department of Microbiology, Immunology, and
Pathology, Colorado State University; Fort Collins, CO USA
Background/Introduction. Chronic wasting disease (CWD) is unique among
prion diseases in its efficient lateral transmission in nature, yet the dynamics
and magnitude of shedding and its immediate and long term consequences remain
unknown. The present study was designed to determine the frequency and time span
in which CWD prions are shed in urine from infected white-tailed deer using
adapted real-time quaking-induced conversion (RT-QuIC) methodology.
Materials and Methods. Longitudinal urine samples were collected by free
catch or catheterization over a 2-year period from oral-route infected [CWD+ (n
= 11)] and aerosol-route-infected [CWD+ (n = 6); CWD- (n = 3)] white-tailed
deer. High speed centrifugation pelleted material from 500 µl of urine was
treated with sodium phosphotungstic acid (Na-PTA), resuspended in 0.05% SDS
buffer, and used as seed in RT-QuIC assays employing recombinant Syrian hamster
prion PrP substrate. Eight (8) replicates of each sample were run and prion
seeding activity was recorded as thioflavin T binding fluorescence (480 nm
emission) using a fluorimeter-shaker. Samples were considered positive if they
crossed an established threshold (5 standard deviations above the negative mean
fluorescence).
Results. In our oral-route inoculation studies, prion seeding activity has
been demonstrated in urine collected at 6 months post-inoculation in 6 of 10
deer (11 of 80 replicates; 14%), and intermittently at later time points in all
11 CWD+ exposed deer. Our aerosol-route inoculation studies also showed prion
seeding activity in urine collected at 6 months post-inoculation in 1 of 2 deer
(3 of 16 replicates; 19%), and intermittently at later time points in 4 of 6
CWD+ exposed deer. Urine from sham-inoculated control deer and all baseline
samples yielded 3 false-positive prion seeding activities (3 of 352 replicates;
0.8%).
Conclusion. CWD prions (as inferred by prion seeding activity by RT-QuIC)
are shed in urine of infected deer as early as 6 months post inoculation and
throughout the subsequent disease course. Further studies are in progress
refining the real-time urinary prion assay sensitivity and we are examining more
closely the excretion time frame, magnitude, and sample variables in
relationship to inoculation route and prionemia in naturally and experimentally
CWD-infected cervids.
Acknowledgments. Support: NIH: RO1-NS-061902 and Morris Animal Foundation:
D12ZO-045
P.158: Structurally and phenotypically different prions in CWD-infected
white-tailed deer
Martin L Daus, Peter Lasch, and Michael Beekes Robert Koch-Institut;
Berlin, Germany
Prions can exist as multiple strains within mammals. We could detect, for
the first time, two distinct chronic wasting disease (CWD) isolates in
white-tailed deer (WTD).
WTD had been challenged with CWD from either mule deer (MD) or WTD.
Brain-derived prions from MD-infected WTD and WTD-infected WTD could be
distinguished by biochemical, biophysical and biological methods. PK-mediated
limited proteolysis at different pH-values indicated conformational differences
between pathological prion proteins (PrPTSE) from MD-infected WTD and
WTD-infected WTD. More specifically, Fouriertransform infrared microspectroscopy
revealed secondary structure differences between highly purified PrPTSE extracts
from MD-infected WTD and WTD-infected WTD. Different sedimentation velocities of
PrPTSE in gradient centrifugations provided additional evidence for structure
differences between prions from MD-infected WTD and WTD-infected WTD. Brain
homogenate from WTD-infected WTD showed a substantially lower seeding activity
on cellular prion protein (PrPC) of Syrian hamsters in protein misfolding cyclic
amplification (PMCA) than its conformationally distinct counterpart from
MD-infected WTD. When hamsters were intracerebrally inoculated with brain tissue
from MD-infected WTD disease could be transmitted, which was not observed after
similar inoculation with brain homogenate from WTD-infected WTD. In an ongoing
macaque-study both CWD-isolates are currently being further tested for their
transmissibility to primates.
P.163: Bayesian hierarchical modeling of chronic wasting disease in
free-ranging white-tailed deer in the eastern U.S.
Tyler S Evans1 and W David Walter2 1Pennsylvania Cooperative Fish and
Wildlife Research Unit; The Pennsylvania State University; University Park, PA
USA; 2US Geological Survey; Pennsylvania Cooperative Fish and Wildlife Research
Unit; The Pennsylvania State University; University Park, PA USA
Introduction. Chronic wasting disease (CWD) is a prion disease that affects
both free-ranging and captive cervid populations. In the past 45 years, CWD has
spread from a single region in Colorado to all bordering states, as well as
Canada, the Midwest and the northeastern United States. In 2005, CWD was
detected in the eastern U.S. in a free-ranging white-tailed deer (Odocoileus
virginianus) killed by a vehicle in West Virginia followed by positives from
Virginia, Maryland, and Pennsylvania. Although considerable information has been
learned about CWD in wildlife from several areas of the U.S. and Canada, little
information is available on spatial epidemiology of disease in the eastern
U.S.
Materials and Methods. In order to develop a CWD surveillance plan for the
region, we determined covariates and the best scale for analysis by exploring
habitat use and estimating the mean size of home range for deer in the central
Appalachian region (6 km2). We conducted Bayesian hierarchical modeling in
WinBUGS on 24 a priori models using 11,320 free-ranging white-tailed deer (69
positive, 11,251 negative) that have been tested for CWD since 2005. Testing for
CWD was conducted using standard protocols on a variety of tissues extracted
from hunter-harvested deer that included retropharyngeal lymph nodes, tonsil
lymph nodes, and the medulla oblongata sectioned at the obex.
Results. We found 94% of models weights were accounted for in our top model
that identified habitats such as developed and open as covariates that increased
the odds of infection for CWD in this region. Contrary to research in the
endemic area of Colorado, we did not identify clay soil as a significant
predictor of disease even though clay soil ranged from 9% to 19% in our study
samples. Furthermore, contrary to results from the recent expansion of CWD into
the agricultural Midwestern U.S. (Wisconsin, Illinois), we identified developed
and open habitats were better predictors of disease occurrence compared to
forest habitat considered more critical to deer population dynamics in the
U.S.
Conclusions. Our results suggested that the odds of infection for CWD is
likely controlled by areas that congregate deer thus increasing direct
transmission (deer-to-deer interactions) or indirect transmission
(deer-to-environment) by sharing or depositing infectious prion proteins in
these preferred habitats. Epidemiology of CWD in the eastern U.S. is likely
controlled by separate factors than found in the Midwestern and endemic areas
for CWD and can assist in performing more efficient surveillance efforts for the
region.
P.178: Longitudinal quantitative analysis of CWD prions shed in saliva of
deer
Davin M Henderson, Nina Garbino, Nathaniel D Denkers, Amy V Nalls, Candace
K Mathiason, and Edward A Hoover Prion Research Center, College of Veterinary
Medicine and Biomedical Sciences, Colorado State University; Fort Collins, CO
USA
Background/Introduction. Chronic Wasting Disease (CWD) is an emergent
rapidly spreading fatal prion disease of cervids (deer, elk and moose). CWD has
now been identified in 22 States (including two new states within the last
year), 2 Canadian provinces, and South Korea. Shedding of infectious prions in
excreta (saliva, urine, feces) may be an important factor in CWD transmission.
Here we apply an adapted version of a rapid in vitro assay [real-time
quaking-induced conversion (RT-QuIC)] to determine the time of onset, length,
pattern, and magnitude of prion shedding in saliva of infected deer.
Materials and Methods. The RT-QuIC assay was performed as previously
described in Henderson et al. PLoS-One (2013). Saliva samples were quantitated
by comparison to a RT-QuIC reaction rate standard curve of a bioassayed obex
sample from a terminally ill cervid.
Results. To better understand the onset and length of CWD prion shedding we
analyzed >150 longitudinally collected, blinded, then randomized saliva
samples from 17 CWD-infected and 3 uninfected white-tailed deer. We observed
prion shedding, as detected by the RT-QuIC assay, as early as 3 months from
inoculation and sustained shedding throughout the disease course in both aerosol
and orally exposed deer. We estimated the infectious lethal dose of prions shed
in saliva from infected deer by comparing real-time reaction rates of saliva
samples to a bioassayed serially diluted brain control. Our results indicate
that as little as 1 ml of saliva from pre-symptomatic infected deer constitutes
a lethal CWD prion dose.
Conclusions. During the pre-symptomatic stage of CWD infection and
throughout the course of disease deer may be shedding multiple LD50 doses per
day in their saliva. CWD prion shedding through saliva and excreta may account
for the unprecedented spread of this prion disease in nature.
Acknowledgments. Supported by NIH grant RO1-NS-061902 and grant D12ZO-045
from the Morris Animal Foundation.
*** 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.
Monday, June 23, 2014
*** PRION 2014 CONFERENCE CHRONIC WASTING DISEASE CWD
Saturday, August 02, 2014
*** Structural effects of PrP polymorphisms on intra- and inter-species
prion transmission
Tuesday, July 01, 2014
*** CHRONIC WASTING DISEASE CWD TSE PRION DISEASE, GAME FARMS, AND
POTENTIAL RISK FACTORS THERE FROM ***
Thursday, July 03, 2014
*** How Chronic Wasting Disease is affecting deer population and what’s the
risk to humans and pets? ***
Monday, August 18, 2014
CWD TSE PRION Singeltary Submission to Indiana Department of Natural
Resources, four out-of-state wildlife disease experts, and to the 14-member
Agriculture and Natural Resources Interim Study Committee
Wednesday, August 20, 2014
Indiana lawmakers discuss deer import ban, as feds decide against it
Sunday, November 3, 2013
Environmental Impact Statements; Availability, etc.: Animal Carcass
Management [Docket No. APHIS-2013-0044]
Saturday, March 15, 2014
Potential role of soil properties in the spread of CWD in western Canada
Friday, February 08, 2013
*** Behavior of Prions in the Environment: Implications for Prion Biology
OPINION AND REPORT ON : THE TREATMENT OF ANIMAL WASTE BY MEANS OF HIGH
TEMPERATURE (150°C, 3 HOURS) AND CORRESPONDING HIGH PRESSURE ALKALINE
HYDROLYSIS.
ADOPTED BY THE SCIENTIFIC STEERING COMMITTEE AT ITS MEETING OF 16 MAY 2002
FINAL OPINION AND REPORT ON : A TREATMENT OF ANIMAL WASTE BY MEANS OF HIGH
TEMPERATURE (150°C, 3 HOURS) AND HIGH PRESSURE ALKALINE HYDROLYSIS.
ADOPTED BY THE SCIENTIFIC STEERING COMMITTEE AT ITS MEETING OF 10-11 APRIL
2003
BSE INQUIRY 1989 TO ...
The BSE Inquiry / Statement No 19B (supplementary) Dr Alan Colchester
Issued 06/08/1999 (not scheduled to give oral evidence)
SECOND STATEMENT TO THE BSE INQUIRY
Dr A Colchester BA BM BCh PhD FRCP Reader in Neurosciences & Computing,
University of Kent at Canterbury; Consultant Neurologist, Guy’s Hospital London
and William Harvey Hospital Ashford April 1999
snip...
88. Natural decay: Infectivity persists for a long time in the environment.
A study by Palsson in 1979 showed how scrapie was contracted by healthy sheep,
after they had grazed on land which had previously been grazed by
scrapie-infected sheep, even though the land had lain fallow for three years
before the healthy sheep were introduced. Brown also quoted an early experiment
of his own (1991), where he had buried scrapie-infected hamster brain and found
that he could still detect substantial infectivity three years later near where
the material had been placed. 89. Potential environmental routes of infection:
Brown discusses the various possible scenarios, including surface or subsurface
deposits of TSE-contaminated material, which would lead to a build-up of
long-lasting infectivity. Birds feeding on animal remains (such as gulls
visiting landfill sites) could disperse infectivity. Other animals could become
vectors if they later grazed on contaminated land. "A further question concerns
the risk of contamination of the surrounding water table or even surface water
channels, by effluents and discarded solid wastes from treatment plants. A
reasonable conclusion is that there is a potential for human infection to result
from environmental contamination by BSE-infected tissue residues. The potential
cannot be quantified because of the huge numbers of uncertainties and
assumptions that attend each stage of the disposal process". These comments,
from a long established authority on TSEs, closely echo my own statements which
were based on a recent examination of all the evidence. 90. Susceptibility: It
is likely that transmissibility of the disease to humans in vivo is probably
low, because sheep that die from scrapie and cattle that die from BSE are
probably a small fraction of the exposed population. However, no definitive data
are available.
91. Recommendations for disposal procedures: Brown recommends that material
which is actually or potentially contaminated by BSE should be: 1) exposed to
caustic soda; 2) thoroughly incinerated under carefully inspected conditions;
and 3) that any residue should be buried in landfill, to a depth which would
minimise any subsequent animal or human exposure, in areas that would not
intersect with any potable water-table source.
92. This review and recommendations from Brown have particular importance.
Brown is one of the world's foremost authorities on TSEs and is a senior
researcher in the US National Institutes of Health (NIH). It is notable that
such a respected authority is forthright in acknowledging the existence of
potential risks, and in identifying the appropriate measures necessary to
safeguard public health. Paper by SM Cousens, L Linsell, PG Smith, Dr M
Chandrakumar, JW Wilesmith, RSG Knight, M Zeidler, G Stewart, RG Will,
"Geographical distribution of variant CJD in the UK (excluding Northern
Ireland)". Lancet 353:18-21, 2 nd January 1999 93. The above paper {Appendix 41
(02/01/99)} (J/L/353/18) examined the possibility that patients with vCJD
(variant CJD) might live closer to rendering factories than would be expected by
chance. All 26 cases of vCJD in the UK with onset up to 31 st August 1998 were
studied. The incubation period of vCJD is not known but by analogy with other
human TSEs could lie within the range 5-25 years. If vCJD had arisen by exposure
to rendering products, such exposure might plausibly have occurred 8-10 years
before the onset of symptoms. The authors were able to obtain the addresses of
all rendering plants in the UK which were in production in 1988. For each case
of vCJD, the distance from the place of residence on 1st January 1998 to the
nearest rendering plant was calculated
snip...
BSE INQUIRY DATA 1989 through the 1990’s REPORT ON BOVINE CARCASE
INCINERATION, incinerations temps., plume, etc. ...tss
some unofficial info. from a source on the inside looking out;
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 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!!!
xxxxxxxxxxx
you can take that with however many grains of salt you wish, and we can
debate these issues all day long, but bottom line, this is not rocket-science,
all one has to do is some experiments and case studies, but for the life of me,
i don't know what they are waiting on?
kind regards, Terry S. Singeltary Sr., Bacliff, Texas USA
more here;
INCINERATION TEMPS
requirements include;
a. after burning to the range of 800 to 1000*C to eliminate smell;
well heck, this is just typical public relations fear factor control. do
you actually think they would spend the extra costs for fuel, for such extreme
heat, just to eliminate smell, when they spread manure all over your veg's. i
think not. what they really meant were any _TSE agents_.
b. Gas scrubbing to eliminate smoke -- though steam may be omitted;
c. Stacks to be fitted with grit arreaters;
snip...
1.2 Visual Imact
It is considered that the requirement for any carcase incinerator disign
would be to ensure that the operations relating to the reception, storage and
decepitation of diseased carcasses must not be publicly visible and that any
part of a carcase could not be removed or interfered with by animals or birds.
REPORT ON BOVINE CARCASE INCINERATION
IF GOD DEMANDED
full text;
snip...see more ;
spreading cwd around...tss
Between 1996 and 2002, chronic wasting disease was diagnosed in 39 herds of
farmed elk in Saskatchewan in a single epidemic. All of these herds were
depopulated as part of the Canadian Food Inspection Agency’s (CFIA) disease
eradication program. Animals, primarily over 12 mo of age, were tested for the
presence CWD prions following euthanasia. Twenty-one of the herds were linked
through movements of live animals with latent CWD from a single infected source
herd in Saskatchewan, 17 through movements of animals from 7 of the secondarily
infected herds.
***The source herd is believed to have become infected via importation of
animals from a game farm in South Dakota where CWD was subsequently diagnosed
(7,4). A wide range in herd prevalence of CWD at the time of herd depopulation
of these herds was observed. Within-herd transmission was observed on some
farms, while the disease remained confined to the introduced animals on other
farms.
spreading cwd around...tss
Friday, May 13, 2011
Chronic Wasting Disease (CWD) outbreaks and surveillance program in the
Republic of Korea Chronic Wasting Disease (CWD) outbreaks and surveillance
program in the Republic of Korea
Hyun-Joo Sohn, Yoon-Hee Lee, Min-jeong Kim, Eun-Im Yun, Hyo-Jin Kim,
Won-Yong Lee, Dong-Seob Tark, In- Soo Cho, Foreign Animal Disease Research
Division, National Veterinary Research and Quarantine Service, Republic of Korea
Chronic wasting disease (CWD) has been recognized as an important prion
disease in native North America deer and Rocky mountain elks. The disease is a
unique member of the transmissible spongiform encephalopathies (TSEs), which
naturally affects only a few species. CWD had been limited to USA and Canada
until 2000.
On 28 December 2000, information from the Canadian government showed that a
total of 95 elk had been exported from farms with CWD to Korea. These consisted
of 23 elk in 1994 originating from the so-called “source farm” in Canada, and 72
elk in 1997, which had been held in pre export quarantine at the “source
farm”.Based on export information of CWD suspected elk from Canada to Korea, CWD
surveillance program was initiated by the Ministry of Agriculture and Forestry
(MAF) in 2001.
All elks imported in 1997 were traced back, however elks imported in 1994
were impossible to identify. CWD control measures included stamping out of all
animals in the affected farm, and thorough cleaning and disinfection of the
premises. In addition, nationwide clinical surveillance of Korean native
cervids, and improved measures to ensure reporting of CWD suspect cases were
implemented.
Total of 9 elks were found to be affected. CWD was designated as a
notifiable disease under the Act for Prevention of Livestock Epidemics in 2002.
Additional CWD cases - 12 elks and 2 elks - were diagnosed in 2004 and
2005.
Since February of 2005, when slaughtered elks were found to be positive,
all slaughtered cervid for human consumption at abattoirs were designated as
target of the CWD surveillance program. Currently, CWD laboratory testing is
only conducted by National Reference Laboratory on CWD, which is the Foreign
Animal Disease Division (FADD) of National Veterinary Research and Quarantine
Service (NVRQS).
In July 2010, one out of 3 elks from Farm 1 which were slaughtered for the
human consumption was confirmed as positive. Consequently, all cervid – 54 elks,
41 Sika deer and 5 Albino deer – were culled and one elk was found to be
positive. Epidemiological investigations were conducted by Veterinary
Epidemiology Division (VED) of NVRQS in collaboration with provincial veterinary
services.
Epidemiologically related farms were found as 3 farms and all cervid at
these farms were culled and subjected to CWD diagnosis. Three elks and 5
crossbreeds (Red deer and Sika deer) were confirmed as positive at farm 2.
All cervids at Farm 3 and Farm 4 – 15 elks and 47 elks – were culled and
confirmed as negative.
Further epidemiological investigations showed that these CWD outbreaks were
linked to the importation of elks from Canada in 1994 based on circumstantial
evidences.
In December 2010, one elk was confirmed as positive at Farm 5.
Consequently, all cervid – 3 elks, 11 Manchurian Sika deer and 20 Sika deer –
were culled and one Manchurian Sika deer and seven Sika deer were found to be
positive. This is the first report of CWD in these sub-species of deer.
Epidemiological investigations found that the owner of the Farm 2 in CWD
outbreaks in July 2010 had co-owned the Farm 5.
In addition, it was newly revealed that one positive elk was introduced
from Farm 6 of Jinju-si Gyeongsang Namdo. All cervid – 19 elks, 15 crossbreed
(species unknown) and 64 Sika deer – of Farm 6 were culled, but all confirmed as
negative.
: Corresponding author: Dr. Hyun-Joo Sohn (+82-31-467-1867, E-mail:
shonhj@korea.kr) 2011 Pre-congress Workshop: TSEs in animals and their
environment 5
Friday, May 13, 2011
Chronic Wasting Disease (CWD) outbreaks and surveillance program in the
Republic of Korea
how many states have $465,000., and can quarantine and purchase there from,
each cwd said infected farm, but how many states can afford this for all the cwd
infected cervid game ranch type farms, and this is just one cwd infected farm,
which had the highest documented infection rate of cwd, documented at 80%.
Tuesday, December 20, 2011
CHRONIC WASTING DISEASE CWD WISCONSIN Almond Deer (Buckhorn Flats) Farm
Update DECEMBER 2011
The CWD infection rate was nearly 80%, the highest ever in a North American
captive herd. RECOMMENDATION: That the Board approve the purchase of 80 acres of
land for $465,000 for the Statewide Wildlife Habitat Program in Portage County
and approve the restrictions on public use of the site.
SUMMARY:
Thursday, March 29, 2012
*** atypical Nor-98 Scrapie has spread from coast to coast in the USA 2012
NIAA Annual Conference April 11-14, 2011San Antonio, Texas
Monday, April 25, 2011
Experimental Oral Transmission of Atypical Scrapie to Sheep
Volume 17, Number 5-May 2011 However, work with transgenic mice has
demonstrated the potential susceptibility of pigs, with the disturbing finding
that the biochemical properties of the resulting PrPSc have changed on
transmission (40).
P03.141
Aspects of the Cerebellar Neuropathology in Nor98
Gavier-Widén, D1; Benestad, SL2; Ottander, L1; Westergren, E1 1National
Veterinary Insitute, Sweden; 2National Veterinary Institute,
Norway Nor98 is a prion disease of old sheep and goats. This atypical form
of scrapie was first described in Norway in 1998. Several features of Nor98 were
shown to be different from classical scrapie including the distribution of
disease associated prion protein (PrPd) accumulation in the brain. The
cerebellum is generally the most affected brain area in Nor98. The study here
presented aimed at adding information on the neuropathology in the cerebellum of
Nor98 naturally affected sheep of various genotypes in Sweden and Norway. A
panel of histochemical and immunohistochemical (IHC) stainings such as IHC for
PrPd, synaptophysin, glial fibrillary acidic protein, amyloid, and cell markers
for phagocytic cells were conducted. The type of histological lesions and tissue
reactions were evaluated. The types of PrPd deposition were characterized. The
cerebellar cortex was regularly affected, even though there was a variation in
the severity of the lesions from case to case. Neuropil vacuolation was more
marked in the molecular layer, but affected also the granular cell layer. There
was a loss of granule cells. Punctate deposition of PrPd was characteristic. It
was morphologically and in distribution identical with that of synaptophysin,
suggesting that PrPd accumulates in the synaptic structures. PrPd was also
observed in the granule cell layer and in the white matter. The pathology
features of Nor98 in the cerebellum of the affected sheep showed similarities
with those of sporadic Creutzfeldt-Jakob disease in humans.
***The pathology features of Nor98 in the cerebellum of the affected sheep
showed similarities with those of sporadic Creutzfeldt-Jakob disease in
humans.
PR-26
NOR98 SHOWS MOLECULAR FEATURES REMINISCENT OF GSS
R. Nonno1, E. Esposito1, G. Vaccari1, E. Bandino2, M. Conte1, B.
Chiappini1, S. Marcon1, M. Di Bari1, S.L. Benestad3, U. Agrimi1 1 Istituto
Superiore di Sanità, Department of Food Safety and Veterinary Public Health,
Rome, Italy (romolo.nonno@iss.it); 2 Istituto Zooprofilattico della Sardegna,
Sassari, Italy; 3 National Veterinary Institute, Department of Pathology, Oslo,
Norway
Molecular variants of PrPSc are being increasingly investigated in sheep
scrapie and are generally referred to as "atypical" scrapie, as opposed to
"classical scrapie". Among the atypical group, Nor98 seems to be the best
identified. We studied the molecular properties of Italian and Norwegian Nor98
samples by WB analysis of brain homogenates, either untreated, digested with
different concentrations of proteinase K, or subjected to enzymatic
deglycosylation. The identity of PrP fragments was inferred by means of
antibodies spanning the full PrP sequence. We found that undigested brain
homogenates contain a Nor98-specific PrP fragment migrating at 11 kDa (PrP11),
truncated at both the C-terminus and the N-terminus, and not N-glycosylated.
After mild PK digestion, Nor98 displayed full-length PrP (FL-PrP) and
N-glycosylated C-terminal fragments (CTF), along with increased levels of PrP11.
Proteinase K digestion curves (0,006-6,4 mg/ml) showed that FL-PrP and CTF are
mainly digested above 0,01 mg/ml, while PrP11 is not entirely digested even at
the highest concentrations, similarly to PrP27-30 associated with classical
scrapie. Above 0,2 mg/ml PK, most Nor98 samples showed only PrP11 and a fragment
of 17 kDa with the same properties of PrP11, that was tentatively identified as
a dimer of PrP11. Detergent solubility studies showed that PrP11 is insoluble in
2% sodium laurylsorcosine and is mainly produced from detergentsoluble,
full-length PrPSc. Furthermore, among Italian scrapie isolates, we found that a
sample with molecular and pathological properties consistent with Nor98 showed
plaque-like deposits of PrPSc in the thalamus when the brain was analysed by
PrPSc immunohistochemistry. Taken together, our results show that the
distinctive pathological feature of Nor98 is a PrP fragment spanning amino acids
~ 90-155. This fragment is produced by successive N-terminal and C-terminal
cleavages from a full-length and largely detergent-soluble PrPSc, is produced in
vivo and is extremely resistant to PK digestion.
*** Intriguingly, these conclusions suggest that some pathological features
of Nor98 are reminiscent of Gerstmann-Sträussler-Scheinker disease.
119
A newly identified type of scrapie agent can naturally infect sheep with
resistant PrP genotypes
Annick Le Dur*,?, Vincent Béringue*,?, Olivier Andréoletti?, Fabienne
Reine*, Thanh Lan Laï*, Thierry Baron§, Bjørn Bratberg¶, Jean-Luc Vilotte?,
Pierre Sarradin**, Sylvie L. Benestad¶, and Hubert Laude*,?? +Author
Affiliations
*Virologie Immunologie Moléculaires and ?Génétique Biochimique et
Cytogénétique, Institut National de la Recherche Agronomique, 78350
Jouy-en-Josas, France; ?Unité Mixte de Recherche, Institut National de la
Recherche Agronomique-Ecole Nationale Vétérinaire de Toulouse, Interactions Hôte
Agent Pathogène, 31066 Toulouse, France; §Agence Française de Sécurité Sanitaire
des Aliments, Unité Agents Transmissibles Non Conventionnels, 69364 Lyon,
France; **Pathologie Infectieuse et Immunologie, Institut National de la
Recherche Agronomique, 37380 Nouzilly, France; and ¶Department of Pathology,
National Veterinary Institute, 0033 Oslo, Norway
***Edited by Stanley B. Prusiner, University of California, San Francisco,
CA (received for review March 21, 2005)
Abstract Scrapie in small ruminants belongs to transmissible spongiform
encephalopathies (TSEs), or prion diseases, a family of fatal neurodegenerative
disorders that affect humans and animals and can transmit within and between
species by ingestion or inoculation. Conversion of the host-encoded prion
protein (PrP), normal cellular PrP (PrPc), into a misfolded form, abnormal PrP
(PrPSc), plays a key role in TSE transmission and pathogenesis. The intensified
surveillance of scrapie in the European Union, together with the improvement of
PrPSc detection techniques, has led to the discovery of a growing number of
so-called atypical scrapie cases. These include clinical Nor98 cases first
identified in Norwegian sheep on the basis of unusual pathological and PrPSc
molecular features and "cases" that produced discordant responses in the rapid
tests currently applied to the large-scale random screening of slaughtered or
fallen animals. Worryingly, a substantial proportion of such cases involved
sheep with PrP genotypes known until now to confer natural resistance to
conventional scrapie. Here we report that both Nor98 and discordant cases,
including three sheep homozygous for the resistant PrPARR allele (A136R154R171),
efficiently transmitted the disease to transgenic mice expressing ovine PrP, and
that they shared unique biological and biochemical features upon propagation in
mice.
*** These observations support the view that a truly infectious TSE agent,
unrecognized until recently, infects sheep and goat flocks and may have
important implications in terms of scrapie control and public health.
Monday, December 1, 2008
When Atypical Scrapie cross species barriers
Authors
Andreoletti O., Herva M. H., Cassard H., Espinosa J. C., Lacroux C., Simon
S., Padilla D., Benestad S. L., Lantier F., Schelcher F., Grassi J., Torres, J.
M., UMR INRA ENVT 1225, Ecole Nationale Veterinaire de Toulouse.France;
ICISA-INlA, Madrid, Spain; CEA, IBiTec-5, DSV, CEA/Saclay, Gif sur Yvette cedex,
France; National Veterinary Institute, Postboks 750 Sentrum, 0106 Oslo, Norway,
INRA IASP, Centre INRA de Tours, 3738O Nouzilly, France.
Content
Atypical scrapie is a TSE occurring in small ruminants and harbouring
peculiar clinical, epidemiological and biochemical properties. Currently this
form of disease is identified in a large number of countries. In this study we
report the transmission of an atypical scrapie isolate through different species
barriers as modeled by transgenic mice (Tg) expressing different species PRP
sequence.
The donor isolate was collected in 1995 in a French commercial sheep flock.
inoculation into AHQ/AHQ sheep induced a disease which had all
neuro-pathological and biochemical characteristics of atypical scrapie.
Transmitted into Transgenic mice expressing either ovine or PrPc, the isolate
retained all the described characteristics of atypical scrapie.
Surprisingly the TSE agent characteristics were dramatically different
v/hen passaged into Tg bovine mice. The recovered TSE agent had biological and
biochemical characteristics similar to those of atypical BSE L in the same mouse
model. Moreover, whereas no other TSE agent than BSE were shown to transmit into
Tg porcine mice, atypical scrapie was able to develop into this model, albeit
with low attack rate on first passage.
Furthermore, after adaptation in the porcine mouse model this prion showed
similar biological and biochemical characteristics than BSE adapted to this
porcine mouse model. Altogether these data indicate.
(i) the unsuspected potential abilities of atypical scrapie to cross
species barriers
(ii) the possible capacity of this agent to acquire new characteristics
when crossing species barrier
These findings raise some interrogation on the concept of TSE strain and on
the origin of the diversity of the TSE agents and could have consequences on
field TSE control measures.
Friday, February 11, 2011
Atypical/Nor98 Scrapie Infectivity in Sheep Peripheral Tissues
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...
R. BRADLEY
1: J Infect Dis 1980 Aug;142(2):205-8
Oral transmission of kuru, Creutzfeldt-Jakob disease, and scrapie to
nonhuman primates.
Gibbs CJ Jr, Amyx HL, Bacote A, Masters CL, Gajdusek DC.
Kuru and Creutzfeldt-Jakob disease of humans and scrapie disease of sheep
and goats were transmitted to squirrel monkeys (Saimiri sciureus) that were
exposed to the infectious agents only by their nonforced consumption of known
infectious tissues. The asymptomatic incubation period in the one monkey exposed
to the virus of kuru was 36 months; that in the two monkeys exposed to the virus
of Creutzfeldt-Jakob disease was 23 and 27 months, respectively; and that in the
two monkeys exposed to the virus of scrapie was 25 and 32 months, respectively.
Careful physical examination of the buccal cavities of all of the monkeys failed
to reveal signs or oral lesions. One additional monkey similarly exposed to kuru
has remained asymptomatic during the 39 months that it has been under
observation.
snip...
The successful transmission of kuru, Creutzfeldt-Jakob disease, and scrapie
by natural feeding to squirrel monkeys that we have reported provides further
grounds for concern that scrapie-infected meat may occasionally give rise in
humans to Creutzfeldt-Jakob disease.
PMID: 6997404
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
emphasised by the finding that some strains of scrapie produce lesions identical
to the once which characterise 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 acrapie problem urgent if the sheep
industry is not to suffer grievously.
snip...
76/10.12/4.6
Nature. 1972 Mar 10;236(5341):73-4.
Transmission of scrapie to the cynomolgus monkey (Macaca fascicularis).
Gibbs CJ Jr, Gajdusek DC.
Nature 236, 73 - 74 (10 March 1972); doi:10.1038/236073a0
Transmission of Scrapie to the Cynomolgus Monkey (Macaca fascicularis)
C. J. GIBBS jun. & D. C. GAJDUSEK
National Institute of Neurological Diseases and Stroke, National Institutes
of Health, Bethesda, Maryland
SCRAPIE has been transmitted to the cynomolgus, or crab-eating, monkey
(Macaca fascicularis) with an incubation period of more than 5 yr from the time
of intracerebral inoculation of scrapie-infected mouse brain. The animal
developed a chronic central nervous system degeneration, with ataxia, tremor and
myoclonus with associated severe scrapie-like pathology of intensive astroglial
hypertrophy and proliferation, neuronal vacuolation and status spongiosus of
grey matter. The strain of scrapie virus used was the eighth passage in Swiss
mice (NIH) of a Compton strain of scrapie obtained as ninth intracerebral
passage of the agent in goat brain, from Dr R. L. Chandler (ARC, Compton,
Berkshire).
Sunday, December 12, 2010
EFSA reviews BSE/TSE infectivity in small ruminant tissues News Story 2
December 2010
Wednesday, January 18, 2012
Selection of Distinct Strain Phenotypes in Mice Infected by Ovine Natural
Scrapie Isolates Similar to CH1641 Experimental Scrapie
Journal of Neuropathology & Experimental Neurology: February 2012 -
Volume 71 - Issue 2 - p 140–147
Thursday, July 14, 2011
Histopathological Studies of "CH1641-Like" Scrapie Sources Versus Classical
Scrapie and BSE Transmitted to Ovine Transgenic Mice (TgOvPrP4)
Wednesday, January 18, 2012
BSE IN GOATS CAN BE MISTAKEN FOR SCRAPIE
February 1, 2012
Thursday, December 23, 2010
Molecular Typing of Protease-Resistant Prion Protein in Transmissible
Spongiform Encephalopathies of Small Ruminants, France, 2002-2009
Volume 17, Number 1 January 2011
Thursday, November 18, 2010
Increased susceptibility of human-PrP transgenic mice to bovine spongiform
encephalopathy following passage in sheep
Monday, December 14, 2009
Similarities between Forms of Sheep Scrapie and Creutzfeldt-Jakob Disease
Are Encoded by Distinct Prion Types
(hmmm, this is getting interesting now...TSS)
Sporadic CJD type 1 and atypical/ Nor98 scrapie are characterized by fine
(reticular) deposits,
see also ;
All of the Heidenhain variants were of the methionine/ methionine type 1
molecular subtype.
see full text ;
Monday, December 14, 2009
Similarities between Forms of Sheep Scrapie and Creutzfeldt-Jakob Disease
Are Encoded by Distinct Prion Types
Sunday, June 29, 2014
Transmissible Spongiform Encephalopathy TSE Prion Disease North America
2014
Tuesday, August 12, 2014
MAD COW USDA TSE PRION COVER UP or JUST IGNORANCE, for the record AUGUST
2014
Sunday, July 06, 2014
Dietary Risk Factors for Sporadic Creutzfeldt-Jakob Disease: A Confirmatory
Case-Control Study
Conclusions—The a priori hypotheses were supported.
*Consumption of various meat products may be one method of transmission of
the infectious agent for sCJD.
Seven main threats for the future linked to prions
***Also, a link is suspected between atypical BSE and some apparently
sporadic cases of Creutzfeldt-Jakob disease in humans. These atypical BSE cases
constitute an unforeseen first threat that could sharply modify the European
approach to prion diseases.
Second threat
snip...
Monday, October 10, 2011
EFSA Journal 2011 The European Response to BSE: A Success Story
snip...
*** but the possibility that a small proportion of human cases so far
classified as "sporadic" CJD are of zoonotic origin could not be excluded.
Moreover, transmission experiments to non-human primates suggest that some TSE
agents in addition to Classical BSE prions in cattle (namely L-type Atypical
BSE, Classical BSE in sheep, transmissible mink encephalopathy (TME) and chronic
wasting disease (CWD) agents) might have zoonotic potential.
snip...
***In addition, non-human primates are specifically susceptible for
atypical BSE as demonstrated by an approximately 50% shortened incubation time
for L-type BSE as compared to C-type. Considering the current scientific
information available, it cannot be assumed that these different BSE types pose
the same human health risks as C-type BSE or that these risks are mitigated by
the same protective measures.
***Infectivity in skeletal muscle of BASE-infected cattle
***feedstuffs- It also suggests a similar cause or source for atypical BSE
in these countries.
Saturday, August 4, 2012
*** Final Feed Investigation Summary – California ATYPICAL L-TYPE BASE BSE
Case - July 2012
Wednesday, May 30, 2012
PO-028: Oral transmission of L-type bovine spongiform encephalopathy
(L-BSE) in primate model Microcebus murinus
***Also, a link is suspected between atypical BSE and some apparently
sporadic cases of Creutzfeldt-Jakob disease in humans.
what’s the big secret about the age and history of this poor gentleman ???
MAD COW COVER UP USA, THE EVIDENCE MOUNTS $$$
Monday, June 02, 2014
*** Confirmed Human BSE aka mad cow Variant CJD vCJD or nvCJD Case in Texas
*** Creutzfeldt-Jakob Disease CJD cases rising North America with Canada
seeing an extreme increase of 48% between 2008 and 2010 ***
Sunday, October 13, 2013
*** CJD TSE Prion Disease Cases in Texas by Year, 2003-2012
Tuesday, April 01, 2014
*** Questions linger in U.S. CJD cases 2005, and still do in 2014
TSS
