TEXAS TAHC BREAKS IT'S SILENCE WITH TWO MORE CASES CWD CAPTIVE DEER
BRINGING TOTAL TO 10 CAPTIVES REPORTED TO DATE
April 1, 2016
New CWD Cases Discovered at Captive Deer Breeding Facilities
AUSTIN – Two new cases of chronic wasting disease (CWD) in Texas captive
deer, including the first confirmed from a live test tonsillar biopsy sample,
have been validated. The Texas Parks and Wildlife Department (TPWD) and Texas
Animal Health Commission (TAHC) are conducting an epidemiological investigation
into these new cases.
One case involves a 3 1/2-year-old captive raised white-tailed doe that was
born and raised on-site and died on-site of natural causes at a deer breeding
facility in Medina County where the disease had not previously been found. Test
samples were submitted in compliance with TAHC herd plan requirements.
The live test finding is from a 2 ½-year-old captive white-tailed buck in
the Uvalde- Medina County deer breeding facility that was the source of a CWD
positive white-tailed buck harvested by a hunter from a release site on the same
ranch.
With these new confirmations, 10 white-tailed deer in or originating from
deer breeding facilities have been confirmed positive for CWD in the state since
the original detection in June 2015.
Tissue samples revealed the presence of CWD prions during testing at the
Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) in College
Station. The samples were submitted to the National Veterinary Services
Laboratory in Ames, Iowa, which validated the suspect findings Friday
evening.
The disease was first recognized in 1967 in captive mule deer in Colorado.
CWD has also been documented in captive and/or free-ranging deer in 24 states
and 2 Canadian provinces. In Texas, the disease was first discovered in 2012 in
free-ranging mule deer along a remote area of the Hueco Mountains near the
Texas-New Mexico border, and last summer was detected in two, separate captive
white-tailed deer breeding facilities in Medina and Lavaca counties.
CWD among cervids is a progressive, fatal disease that commonly results in
altered behavior as a result of microscopic changes made to the brain of
affected animals. An animal may carry the disease for years without outward
indication, but in the latter stages, signs may include listlessness, lowering
of the head, weight loss, repetitive walking in set patterns and a lack of
responsiveness. To date there is no evidence that CWD poses a risk to humans or
non-cervids. However, as a precaution, the U.S. Centers for Disease Control and
the World Health Organization recommend not to consume meat from infected
animals.
More information on CWD can be found on TPWD’s website, http://www.tpwd.texas.gov/CWD or at the
Chronic Wasting Disease Alliance website, http://www.cwd-info.org.
More information about the TAHC CWD program may be found at http://www.tahc.state.tx.us/animal_health/cwd/cwd.html
###
>>>One case involves a 3 1/2-year-old captive raised white-tailed
doe that was born and raised on-site and died on-site of natural causes at a
deer breeding facility in Medina County where the disease had not previously
been found. <<<
which came first, the chicken or the egg. that would be like you dying from
CJD or Asbestosis, yet your death certificate says congestive heart failure for
cause of death. you must then get the death certificate changed to read the
actual cause of death. ...
TEXAS CWD TESTING TOTAL FIGURES ??? anyone’s guess to date. TAHC et al
should take up Arkansas reporting of test results to the public and open
discussion. ...
Friday, February 26, 2016
TEXAS Hartley County Mule Deer Tests Positive for Chronic Wasting Disease
CWD TSE Prion
Friday, February 05, 2016
TEXAS NEW CHRONIC WASTING DISEASE CWD CASE DISCOVERD AT CAPTIVE DEER
RELEASE SITE
April 1, 2016
New CWD Cases Discovered at Captive Deer Breeding Facilities
AUSTIN – Two new cases of chronic wasting disease (CWD) in Texas captive
deer, including the first confirmed from a live test tonsillar biopsy sample,
have been validated. The Texas Parks and Wildlife Department (TPWD) and Texas
Animal Health Commission (TAHC) are conducting an epidemiological investigation
into these new cases.
One case involves a 3 1/2-year-old captive raised white-tailed doe that was
born and raised on-site and died on-site of natural causes at a deer breeding
facility in Medina County where the disease had not previously been found. Test
samples were submitted in compliance with TAHC herd plan requirements.
The live test finding is from a 2 ½-year-old captive white-tailed buck in
the Uvalde- Medina County deer breeding facility that was the source of a CWD
positive white-tailed buck harvested by a hunter from a release site on the same
ranch.
With these new confirmations, 10 white-tailed deer in or originating from
deer breeding facilities have been confirmed positive for CWD in the state since
the original detection in June 2015.
Tissue samples revealed the presence of CWD prions during testing at the
Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) in College
Station. The samples were submitted to the National Veterinary Services
Laboratory in Ames, Iowa, which validated the suspect findings Friday
evening.
The disease was first recognized in 1967 in captive mule deer in Colorado.
CWD has also been documented in captive and/or free-ranging deer in 24 states
and 2 Canadian provinces. In Texas, the disease was first discovered in 2012 in
free-ranging mule deer along a remote area of the Hueco Mountains near the
Texas-New Mexico border, and last summer was detected in two, separate captive
white-tailed deer breeding facilities in Medina and Lavaca counties.
CWD among cervids is a progressive, fatal disease that commonly results in
altered behavior as a result of microscopic changes made to the brain of
affected animals. An animal may carry the disease for years without outward
indication, but in the latter stages, signs may include listlessness, lowering
of the head, weight loss, repetitive walking in set patterns and a lack of
responsiveness. To date there is no evidence that CWD poses a risk to humans or
non-cervids. However, as a precaution, the U.S. Centers for Disease Control and
the World Health Organization recommend not to consume meat from infected
animals.
More information on CWD can be found on TPWD’s website, http://www.tpwd.texas.gov/CWD or at the
Chronic Wasting Disease Alliance website, http://www.cwd-info.org.
More information about the TAHC CWD program may be found at http://www.tahc.state.tx.us/animal_health/cwd/cwd.html
###
>>>One case involves a 3 1/2-year-old captive raised white-tailed
doe that was born and raised on-site and died on-site of natural causes at a
deer breeding facility in Medina County where the disease had not previously
been found. <<<
which came first, the chicken or the egg. that would be like you dying from
CJD or Asbestosis, yet your death certificate says congestive heart failure for
cause of death. you must then get the death certificate changed to read the
actual cause of death. ...
TEXAS CWD TESTING TOTAL FIGURES ??? anyone’s guess to date. TAHC et al
should take up Arkansas reporting of test results to the public and open
discussion. ...
Friday, February 26, 2016
TEXAS Hartley County Mule Deer Tests Positive for Chronic Wasting Disease
CWD TSE Prion
Friday, February 05, 2016
TEXAS NEW CHRONIC WASTING DISEASE CWD CASE DISCOVERD AT CAPTIVE DEER
RELEASE SITE
Friday, April 01, 2016
ARKANSAS CHRONIC WASTING DISEASE CWD TSE PRION CASES EXPLODE BY 27 NEW
CASES WITH 50 CASES TOTAL TO DATE
Friday, April 01, 2016
Arkansas confirms six more cases of CWD bringing total to 56 since first
reported 2 months ago
http://chronic-wasting-disease.blogspot.com/2016/04/arkansas-confirms-six-more-cases-of-cwd.html
Thursday, March 31, 2016
Chronic Wasting Disease CWD TSE Prion Roundup USA April 1, 2016
I strenuously once again urge the FDA and its industry constituents, to
make it MANDATORY that all ruminant feed be banned to all ruminants, and this
should include all cervids, as well as non-ruminants such as cats and dogs as
well, as soon as possible for the following reasons...
31 Jan 2015 at 20:14 GMT
*** Ruminant feed ban for cervids in the United States? ***
31 Jan 2015 at 20:14 GMT
see Singeltary comment ;
*** PLEASE SEE THIS URGENT UPDATE ON CWD AND FEED ANIMAL PROTEIN ***
Sunday, March 20, 2016
Docket No. FDA-2003-D-0432 (formerly 03D-0186) Use of Material from Deer
and Elk in Animal Feed ***UPDATED MARCH 2016*** Singeltary Submission
Monday, March 28, 2016
National Scrapie Eradication Program February 2016 Monthly Report
Docket No. FDA-2003-D-0432 (formerly 03D-0186) Use of Material from Deer
and Elk in Animal Feed Singeltary Submission
Greetings again FDA and Mr. Pritchett et al,
I would kindly like to comment on ;
Docket No. FDA-2003-D-0432 (formerly 03D-0186) Use of Material from Deer
and Elk in Animal Feed Singeltary Submission
#158
Guidance for Industry
Use of Material from Deer and Elk in Animal Feed
This version of the guidance replaces the version made available
September15, 2003.
This document has been revised to update the docket number, contact
information, and standard disclosures. Submit comments on this guidance at any
time.
Submit electronic comments to http://www.regulations.gov. Submit written
comments to the Division of Dockets Management (HFA-305), Food and Drug
Administration, 5630 Fishers Lane, Rm. 1061, Rockville, MD 20852. All comments
should be identified with the Docket No. FDA-2003-D-0432 (formerly 03D-0186).
For further information regarding this guidance, contact Burt Pritchett,
Center for Veterinary Medicine (HFV-222), Food and Drug Administration, 7519
Standish Place, Rockville, MD 20855, 240-402-6276, E-mail:
burt.pritchett@fda.hhs.gov.
Additional copies of this guidance document may be requested from the
Policy and Regulations Staff (HFV-6), Center for Veterinary Medicine, Food and
Drug Administration, 7519 Standish Place, Rockville, MD 20855, and may be viewed
on the Internet at either http://www.fda.gov/AnimalVeterinary/default.htm
or http://www.regulations.gov.
U.S. Department of Health and Human Services Food and Drug Administration
Center for Veterinary Medicine March 2016
Contains Nonbinding Recommendations
2
Guidance for Industry Use of Material from Deer and Elk in Animal Feed
This guidance represents the current thinking of the Food and Drug
Administration (FDA or Agency) on this topic. It does not establish any rights
for any person and is not binding on FDA or the public. You can use an
alternative approach if it satisfies the requirements of the applicable statutes
and regulations. To discuss an alternative approach, contact the FDA office
responsible for this guidance as listed on the title page.
I. Introduction
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.
In general, FDA’s guidance documents 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.
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, 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.
Contains Nonbinding Recommendations
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.
3
Docket No. FDA-2003-D-0432 (formerly 03D-0186) Use of Material from Deer
and Elk in Animal Feed Singeltary Submission
Greetings again FDA and Mr. Pritchett et al,
MY comments and source reference of sound science on this very important
issue are as follows ;
Docket No. FDA-2003-D-0432 (formerly 03D-0186) Use of Material from Deer
and Elk in Animal Feed Singeltary Submission
I kindly wish to once again submit to Docket No. FDA-2003-D-0432 (formerly
03D-0186) Use of Material from Deer and Elk in Animal Feed.
Thank you kindly for allowing me to comment again, ...and again...and
again, on a topic so important, why it is ‘NON-BINDING’ is beyond me.
this should have been finalized and made ‘BINDING’ or MANDATORY OVER A
DECADE AGO.
but here lay the problem, once made ‘BINDING’ or ‘MANDATORY’, it is still
nothing but ink on paper.
we have had a mad cow feed ban in place since August 1997, and since then,
literally 100s of millions of pounds BANNED MAD COW FEED has been sent out to
commerce and fed out (see reference materials).
ENFORCEMENT OF SAID BINDING REGULATIONS HAS FAILED US TOO MANY TIMES.
so, in my opinion, any non-binding or voluntary regulations will not work,
and to state further, ‘BINDING’ or MANDATORY regulations will not work unless
enforced.
with that said, we know that Chronic Wasting Disease CWD TSE Prion easily
transmits to other cervid through the oral route.
the old transmission studies of BSE TSE floored scientist once they figured
out what they had, and please don’t forget about those mink that were fed 95%+
dead stock downer cow, that all came down with TME. please see ;
It is clear that the designing scientists must also have shared Mr Bradleys
surprise at the results because all the dose levels right down to 1 gram
triggered infection.
it is clear that the designing scientists must have also shared Mr Bradleys
surprise at the results because all the dose levels right down to 1 gram
triggered infection.
Evidence That Transmissible Mink Encephalopathy Results from Feeding
Infected Cattle
Over the next 8-10 weeks, approximately 40% of all the adult mink on the
farm died from TME.
snip...
The rancher was a ''dead stock'' feeder using mostly (>95%) downer or
dead dairy cattle...
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...
please see further ;
REFERENCE MATERIALS
*** Docket No. APHIS-2007-0127 Scrapie in Sheep and Goats Terry Singeltary
Sr. Submission ***
Monday, November 16, 2015
*** Docket No. APHIS-2007-0127 Scrapie in Sheep and Goats Terry Singeltary
Sr. Submission ***
Friday, February 05, 2016
*** Report of the Committee on Wildlife Diseases FY2015 CWD TSE PRION
Detections in Farmed Cervids and Wild
Saturday, February 6, 2016
*** Secretary's Advisory Committee on Animal Health; Meeting [Docket No.
APHIS-2016-0007] Singeltary Submission
Friday, August 14, 2015
*** Susceptibility of cattle to the agent of chronic wasting disease from
elk after intracranial inoculation
O.05: Transmission of prions to primates after extended silent incubation
periods: Implications for BSE and scrapie risk assessment in human populations
Emmanuel Comoy, Jacqueline Mikol, Valerie Durand, Sophie Luccantoni,
Evelyne Correia, Nathalie Lescoutra, Capucine Dehen, and Jean-Philippe Deslys
Atomic Energy Commission; Fontenay-aux-Roses, France
Prion diseases (PD) are the unique neurodegenerative proteinopathies
reputed to be transmissible under field conditions since decades. The
transmission of Bovine Spongiform Encephalopathy (BSE) to humans evidenced that
an animal PD might be zoonotic under appropriate conditions. Contrarily, in the
absence of obvious (epidemiological or experimental) elements supporting a
transmission or genetic predispositions, PD, like the other proteinopathies, are
reputed to occur spontaneously (atpical animal prion strains, sporadic CJD
summing 80% of human prion cases). Non-human primate models provided the first
evidences supporting the transmissibiity of human prion strains and the zoonotic
potential of BSE. Among them, cynomolgus macaques brought major information for
BSE risk assessment for human health (Chen, 2014), according to their
phylogenetic proximity to humans and extended lifetime. We used this model to
assess the zoonotic potential of other animal PD from bovine, ovine and cervid
origins even after very long silent incubation periods.
*** We recently observed the direct transmission of a natural classical
scrapie isolate to macaque after a 10-year silent incubation period,
***with features similar to some reported for human cases of sporadic CJD,
albeit requiring fourfold long incubation than BSE. Scrapie, as recently evoked
in humanized mice (Cassard, 2014),
***is the third potentially zoonotic PD (with BSE and L-type BSE),
***thus questioning the origin of human sporadic cases.
We will present an updated panorama of our different transmission studies
and discuss the implications of such extended incubation periods on risk
assessment of animal PD for human health.
===============
***thus questioning the origin of human sporadic cases***
===============
Research Project: TRANSMISSION, DIFFERENTIATION, AND PATHOBIOLOGY OF
TRANSMISSIBLE SPONGIFORM ENCEPHALOPATHIES
*** Title: Transmission of scrapie prions to primate after an extended
silent incubation period
Authors
item Comoy, Emmanuel - item Mikol, Jacqueline - item Luccantoni-Freire,
Sophie - item Correia, Evelyne - item Lescoutra-Etchegaray, Nathalie - item
Durand, Valérie - item Dehen, Capucine - item Andreoletti, Olivier - item
Casalone, Cristina - item Richt, Juergen item Greenlee, Justin item Baron,
Thierry - item Benestad, Sylvie - item Hills, Bob - item Brown, Paul - item
Deslys, Jean-Philippe -
Submitted to: Scientific Reports Publication Type: Peer Reviewed Journal
Publication Acceptance Date: May 28, 2015 Publication Date: June 30, 2015
Citation: Comoy, E.E., Mikol, J., Luccantoni-Freire, S., Correia, E.,
Lescoutra-Etchegaray, N., Durand, V., Dehen, C., Andreoletti, O., Casalone, C.,
Richt, J.A., Greenlee, J.J., Baron, T., Benestad, S., Brown, P., Deslys, J.
2015. Transmission of scrapie prions to primate after an extended silent
incubation period. Scientific Reports. 5:11573.
Interpretive Summary: The transmissible spongiform encephalopathies (also
called prion diseases) are fatal neurodegenerative diseases that affect animals
and humans. The agent of prion diseases is a misfolded form of the prion protein
that is resistant to breakdown by the host cells. Since all mammals express
prion protein on the surface of various cells such as neurons, all mammals are,
in theory, capable of replicating prion diseases. One example of a prion
disease, bovine spongiform encephalopathy (BSE; also called mad cow disease),
has been shown to infect cattle, sheep, exotic undulates, cats, non-human
primates, and humans when the new host is exposed to feeds or foods contaminated
with the disease agent. The purpose of this study was to test whether non-human
primates (cynomologous macaque) are susceptible to the agent of sheep scrapie.
***After an incubation period of approximately 10 years a macaque developed
progressive clinical signs suggestive of neurologic disease.
***Upon postmortem examination and microscopic examination of tissues,
there was a widespread distribution of lesions consistent with a transmissible
spongiform encephalopathy.
***This information will have a scientific impact since it is the first
study that demonstrates the transmission of scrapie to a non-human primate with
a close genetic relationship to humans.
***This information is especially useful to regulatory officials and those
involved with risk assessment of the potential transmission of animal prion
diseases to humans.
Technical Abstract:
Classical bovine spongiform encephalopathy (c-BSE) is an animal prion
disease that also causes variant Creutzfeldt-Jakob disease in humans. Over the
past decades, c-BSE's zoonotic potential has been the driving force in
establishing extensive protective measures for animal and human health.
***In complement to the recent demonstration that humanized mice are
susceptible to scrapie, we report here the first observation of direct
transmission of a natural classical scrapie isolate to a macaque after a 10-year
incubation period.
***Neuropathologic examination revealed all of the features of a prion
disease: spongiform change, neuronal loss, and accumulation of PrPres throughout
the CNS.
***This observation strengthens the questioning of the harmlessness of
scrapie to humans, at a time when protective measures for human and animal
health are being dismantled and reduced as c-BSE is considered controlled and
being eradicated.
***Our results underscore the importance of precautionary and protective
measures and the necessity for long-term experimental transmission studies to
assess the zoonotic potential of other animal prion strains.
***Our study demonstrates susceptibility of adult cattle to oral
transmission of classical BSE. ***
***our findings suggest that possible transmission risk of H-type BSE to
sheep and human. ***
P.86: Estimating the risk of transmission of BSE and scrapie to ruminants
and humans by protein misfolding cyclic amplification
Morikazu Imamura, Naoko Tabeta, Yoshifumi Iwamaru, and Yuichi Murayama
National Institute of Animal Health; Tsukuba, Japan
To assess the risk of the transmission of ruminant prions to ruminants and
humans at the molecular level, we investigated the ability of abnormal prion
protein (PrPSc) of typical and atypical BSEs (L-type and H-type) and typical
scrapie to convert normal prion protein (PrPC) from bovine, ovine, and human to
proteinase K-resistant PrPSc-like form (PrPres) using serial protein misfolding
cyclic amplification (PMCA).
Six rounds of serial PMCA was performed using 10% brain homogenates from
transgenic mice expressing bovine, ovine or human PrPC in combination with PrPSc
seed from typical and atypical BSE- or typical scrapie-infected brain
homogenates from native host species. In the conventional PMCA, the conversion
of PrPC to PrPres was observed only when the species of PrPC source and PrPSc
seed matched. However, in the PMCA with supplements (digitonin, synthetic polyA
and heparin), both bovine and ovine PrPC were converted by PrPSc from all tested
prion strains. On the other hand, human PrPC was converted by PrPSc from typical
and H-type BSE in this PMCA condition.
Although these results were not compatible with the previous reports
describing the lack of transmissibility of H-type BSE to ovine and human
transgenic mice,
***our findings suggest that possible transmission risk of H-type BSE to
sheep and human.
Bioassay will be required to determine whether the PMCA products are
infectious to these animals.
================
==========================================
PRION 2015 CONFERENCE FT. COLLINS CWD RISK FACTORS TO HUMANS
*** LATE-BREAKING ABSTRACTS PRION 2015 CONFERENCE ***
O18
Zoonotic Potential of CWD Prions
Liuting Qing1, Ignazio Cali1,2, Jue Yuan1, Shenghai Huang3, Diane Kofskey1,
Pierluigi Gambetti1, Wenquan Zou1, Qingzhong Kong1 1Case Western Reserve
University, Cleveland, Ohio, USA, 2Second University of Naples, Naples, Italy,
3Encore Health Resources, Houston, Texas, USA
*** These results indicate that the CWD prion has the potential to infect
human CNS and peripheral lymphoid tissues and that there might be asymptomatic
human carriers of CWD infection.
==================
***These results indicate that the CWD prion has the potential to infect
human CNS and peripheral lymphoid tissues and that there might be asymptomatic
human carriers of CWD infection.***
==================
P.105: RT-QuIC models trans-species prion transmission
Kristen Davenport, Davin Henderson, Candace Mathiason, and Edward Hoover
Prion Research Center; Colorado State University; Fort Collins, CO USA
Conversely, FSE maintained sufficient BSE characteristics to more
efficiently convert bovine rPrP than feline rPrP. Additionally, human rPrP was
competent for conversion by CWD and fCWD.
***This insinuates that, at the level of protein:protein interactions, the
barrier preventing transmission of CWD to humans is less robust than previously
estimated.
================
***This insinuates that, at the level of protein:protein interactions, the
barrier preventing transmission of CWD to humans is less robust than previously
estimated.***
================
*** PRICE OF CWD TSE PRION POKER GOES UP 2014 ***
Transmissible Spongiform Encephalopathy TSE PRION update January 2, 2014
*** chronic wasting disease, there was no absolute barrier to conversion of
the human prion protein.
*** Furthermore, the form of human PrPres produced in this in vitro assay
when seeded with CWD, resembles that found in the most common human prion
disease, namely sCJD of the MM1 subtype.
*** These results would seem to suggest that CWD does indeed have zoonotic
potential, at least as judged by the compatibility of CWD prions and their human
PrPC target. Furthermore, extrapolation from this simple in vitro assay suggests
that if zoonotic CWD occurred, it would most likely effect those of the PRNP
codon 129-MM genotype and that the PrPres type would be similar to that found in
the most common subtype of sCJD (MM1).***
*** 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.
now, let’s see what the authors said about this casual link, personal
communications years ago. see where it is stated NO STRONG evidence. so, does
this mean there IS casual evidence ???? “Our conclusion stating that we found no
strong evidence of CWD transmission to humans”
From: TSS (216-119-163-189.ipset45.wt.net)
Subject: CWD aka MAD DEER/ELK TO HUMANS ???
Date: September 30, 2002 at 7:06 am PST
From: "Belay, Ermias"
To: Cc: "Race, Richard (NIH)" ; ; "Belay, Ermias"
Sent: Monday, September 30, 2002 9:22 AM
Subject: RE: TO CDC AND NIH - PUB MED- 3 MORE DEATHS - CWD - YOUNG HUNTERS
Dear Sir/Madam,
In the Archives of Neurology you quoted (the abstract of which was attached
to your email), we did not say CWD in humans will present like variant CJD. That
assumption would be wrong. I encourage you to read the whole article and call me
if you have questions or need more clarification (phone: 404-639-3091). Also, we
do not claim that "no-one has ever been infected with prion disease from eating
venison." Our conclusion stating that we found no strong evidence of CWD
transmission to humans in the article you quoted or in any other forum is
limited to the patients we investigated.
Ermias Belay, M.D. Centers for Disease Control and Prevention
-----Original Message-----
From: Sent: Sunday, September 29, 2002 10:15 AM
To: rr26k@nih.gov; rrace@niaid.nih.gov; ebb8@CDC.GOV
Subject: TO CDC AND NIH - PUB MED- 3 MORE DEATHS - CWD - YOUNG HUNTERS
Sunday, November 10, 2002 6:26 PM ......snip........end..............TSS
Thursday, April 03, 2008
A prion disease of cervids: Chronic wasting disease 2008 1: Vet Res. 2008
Apr 3;39(4):41 A prion disease of cervids: Chronic wasting disease Sigurdson CJ.
snip...
*** twenty-seven CJD patients who regularly consumed venison were reported
to the Surveillance Center***,
snip... full text ;
CJD is so rare in people under age 30, one case in a billion (leaving out
medical mishaps), that four cases under 30 is "very high," says Colorado
neurologist Bosque. "Then, if you add these other two from Wisconsin [cases in
the newspaper], six cases of CJD in people associated with venison is very, very
high." Only now, with Mary Riley, there are at least seven, and possibly eight,
with Steve, her dining companion. "It's not critical mass that matters,"
however, Belay says. "One case would do it for me." The chance that two people
who know each other would both contact CJD, like the two Wisconsin sportsmen, is
so unlikely, experts say, it would happen only once in 140 years.
Given the incubation period for TSEs in humans, it may require another
generation to write the final chapter on CWD in Wisconsin. "Does chronic wasting
disease pass into humans? We'll be able to answer that in 2022," says Race.
Meanwhile, the state has become part of an immense experiment.
I urge everyone to watch this video closely...terry
*** you can see video here and interview with Jeff's Mom, and scientist
telling you to test everything and potential risk factors for humans ***
Envt.07:
Pathological Prion Protein (PrPTSE) in Skeletal Muscles of Farmed and Free
Ranging White-Tailed Deer Infected with Chronic Wasting Disease
***The presence and seeding activity of PrPTSE in skeletal muscle from
CWD-infected cervids suggests prevention of such tissue in the human diet as a
precautionary measure for food safety, pending on further clarification of
whether CWD may be transmissible to humans.
Prions in Skeletal Muscles of Deer with Chronic Wasting Disease Rachel C.
Angers1,*, Shawn R. Browning1,*,†, Tanya S. Seward2, Christina J. Sigurdson4,‡,
Michael W. Miller5, Edward A. Hoover4, Glenn C. Telling1,2,3,§ snip...
Abstract The emergence of chronic wasting disease (CWD) in deer and elk in
an increasingly wide geographic area, as well as the interspecies transmission
of bovine spongiform encephalopathy to humans in the form of variant Creutzfeldt
Jakob disease, have raised concerns about the zoonotic potential of CWD. Because
meat consumption is the most likely means of exposure, it is important to
determine whether skeletal muscle of diseased cervids contains prion
infectivity. Here bioassays in transgenic mice expressing cervid prion protein
revealed the presence of infectious prions in skeletal muscles of CWD-infected
deer, demonstrating that humans consuming or handling meat from CWD-infected
deer are at risk to prion exposure.
***********CJD REPORT 1994 increased risk for consumption of veal and
venison and lamb***********
CREUTZFELDT JAKOB DISEASE SURVEILLANCE IN THE UNITED KINGDOM THIRD ANNUAL
REPORT AUGUST 1994
Consumption of venison and veal was much less widespread among both cases
and controls. For both of these meats there was evidence of a trend with
increasing frequency of consumption being associated with increasing risk of
CJD. (not nvCJD, but sporadic CJD...tss)
These associations were largely unchanged when attention was restricted to
pairs with data obtained from relatives. ...
Table 9 presents the results of an analysis of these data.
There is STRONG evidence of an association between ‘’regular’’ veal eating
and risk of CJD (p = .0.01).
Individuals reported to eat veal on average at least once a year appear to
be at 13 TIMES THE RISK of individuals who have never eaten veal.
There is, however, a very wide confidence interval around this estimate.
There is no strong evidence that eating veal less than once per year is
associated with increased risk of CJD (p = 0.51).
The association between venison eating and risk of CJD shows similar
pattern, with regular venison eating associated with a 9 FOLD INCREASE IN RISK
OF CJD (p = 0.04).
There is some evidence that risk of CJD INCREASES WITH INCREASING FREQUENCY
OF LAMB EATING (p = 0.02).
The evidence for such an association between beef eating and CJD is weaker
(p = 0.14). When only controls for whom a relative was interviewed are included,
this evidence becomes a little STRONGER (p = 0.08).
snip...
It was found that when veal was included in the model with another
exposure, the association between veal and CJD remained statistically
significant (p = < 0.05 for all exposures), while the other exposures
ceased to be statistically significant (p = > 0.05).
snip...
In conclusion, an analysis of dietary histories revealed statistical
associations between various meats/animal products and INCREASED RISK OF CJD.
When some account was taken of possible confounding, the association between
VEAL EATING AND RISK OF CJD EMERGED AS THE STRONGEST OF THESE ASSOCIATIONS
STATISTICALLY. ...
snip...
In the study in the USA, a range of foodstuffs were associated with an
increased risk of CJD, including liver consumption which was associated with an
apparent SIX-FOLD INCREASE IN THE RISK OF CJD. By comparing the data from 3
studies in relation to this particular dietary factor, the risk of liver
consumption became non-significant with an odds ratio of 1.2 (PERSONAL
COMMUNICATION, PROFESSOR A. HOFMAN. ERASMUS UNIVERSITY, ROTTERDAM). (???...TSS)
snip...see full report ;
CJD9/10022
October 1994
Mr R.N. Elmhirst Chairman British Deer Farmers Association Holly Lodge
Spencers Lane BerksWell Coventry CV7 7BZ
Dear Mr Elmhirst,
CREUTZFELDT-JAKOB DISEASE (CJD) SURVEILLANCE UNIT REPORT
Thank you for your recent letter concerning the publication of the third
annual report from the CJD Surveillance Unit. I am sorry that you are
dissatisfied with the way in which this report was published.
The Surveillance Unit is a completely independant outside body and the
Department of Health is committed to publishing their reports as soon as they
become available. In the circumstances it is not the practice to circulate the
report for comment since the findings of the report would not be amended. In
future we can ensure that the British Deer Farmers Association receives a copy
of the report in advance of publication.
The Chief Medical Officer has undertaken to keep the public fully informed
of the results of any research in respect of CJD. This report was entirely the
work of the unit and was produced completely independantly of the the
Department.
The statistical results reqarding the consumption of venison was put into
perspective in the body of the report and was not mentioned at all in the press
release. Media attention regarding this report was low key but gave a realistic
presentation of the statistical findings of the Unit. This approach to
publication was successful in that consumption of venison was highlighted only
once by the media ie. in the News at one television proqramme.
I believe that a further statement about the report, or indeed statistical
links between CJD and consumption of venison, would increase, and quite possibly
give damaging credence, to the whole issue. From the low key media reports of
which I am aware it seems unlikely that venison consumption will suffer
adversely, if at all.
http://web.archive.org/web/20030511010117/http://www.bseinquiry.gov.uk/files/yb/1994/10/00003001.pdf
*** These results would seem to suggest that CWD does indeed have zoonotic
potential, at least as judged by the compatibility of CWD prions and their human
PrPC target. Furthermore, extrapolation from this simple in vitro assay suggests
that if zoonotic CWD occurred, it would most likely effect those of the PRNP
codon 129-MM genotype and that the PrPres type would be similar to that found in
the most common subtype of sCJD (MM1).***
O.05: Transmission of prions to primates after extended silent incubation
periods: Implications for BSE and scrapie risk assessment in human populations
Emmanuel Comoy, Jacqueline Mikol, Valerie Durand, Sophie Luccantoni,
Evelyne Correia, Nathalie Lescoutra, Capucine Dehen, and Jean-Philippe Deslys
Atomic Energy Commission; Fontenay-aux-Roses, France
Prion diseases (PD) are the unique neurodegenerative proteinopathies
reputed to be transmissible under field conditions since decades. The
transmission of Bovine Spongiform Encephalopathy (BSE) to humans evidenced that
an animal PD might be zoonotic under appropriate conditions. Contrarily, in the
absence of obvious (epidemiological or experimental) elements supporting a
transmission or genetic predispositions, PD, like the other proteinopathies, are
reputed to occur spontaneously (atpical animal prion strains, sporadic CJD
summing 80% of human prion cases). Non-human primate models provided the first
evidences supporting the transmissibiity of human prion strains and the zoonotic
potential of BSE. Among them, cynomolgus macaques brought major information for
BSE risk assessment for human health (Chen, 2014), according to their
phylogenetic proximity to humans and extended lifetime. We used this model to
assess the zoonotic potential of other animal PD from bovine, ovine and cervid
origins even after very long silent incubation periods.
*** We recently observed the direct transmission of a natural classical
scrapie isolate to macaque after a 10-year silent incubation period,
***with features similar to some reported for human cases of sporadic CJD,
albeit requiring fourfold long incubation than BSE. Scrapie, as recently evoked
in humanized mice (Cassard, 2014),
***is the third potentially zoonotic PD (with BSE and L-type BSE),
***thus questioning the origin of human sporadic cases. We will present an
updated panorama of our different transmission studies and discuss the
implications of such extended incubation periods on risk assessment of animal PD
for human health.
===============
***thus questioning the origin of human sporadic cases***
===============
***our findings suggest that possible transmission risk of H-type BSE to
sheep and human. Bioassay will be required to determine whether the PMCA
products are infectious to these animals.
==============
Research Project: TRANSMISSION, DIFFERENTIATION, AND PATHOBIOLOGY OF
TRANSMISSIBLE SPONGIFORM ENCEPHALOPATHIES
Title: Transmission of scrapie prions to primate after an extended silent
incubation period
Authors
item Comoy, Emmanuel - item Mikol, Jacqueline - item Luccantoni-Freire,
Sophie - item Correia, Evelyne - item Lescoutra-Etchegaray, Nathalie - item
Durand, Valérie - item Dehen, Capucine - item Andreoletti, Olivier - item
Casalone, Cristina - item Richt, Juergen item Greenlee, Justin item Baron,
Thierry - item Benestad, Sylvie - item Hills, Bob - item Brown, Paul - item
Deslys, Jean-Philippe -
Submitted to: Scientific Reports Publication Type: Peer Reviewed Journal
Publication Acceptance Date: May 28, 2015 Publication Date: June 30, 2015
Citation: Comoy, E.E., Mikol, J., Luccantoni-Freire, S., Correia, E.,
Lescoutra-Etchegaray, N., Durand, V., Dehen, C., Andreoletti, O., Casalone, C.,
Richt, J.A., Greenlee, J.J., Baron, T., Benestad, S., Brown, P., Deslys, J.
2015. Transmission of scrapie prions to primate after an extended silent
incubation period. Scientific Reports. 5:11573.
Interpretive Summary: The transmissible spongiform encephalopathies (also
called prion diseases) are fatal neurodegenerative diseases that affect animals
and humans. The agent of prion diseases is a misfolded form of the prion protein
that is resistant to breakdown by the host cells. Since all mammals express
prion protein on the surface of various cells such as neurons, all mammals are,
in theory, capable of replicating prion diseases. One example of a prion
disease, bovine spongiform encephalopathy (BSE; also called mad cow disease),
has been shown to infect cattle, sheep, exotic undulates, cats, non-human
primates, and humans when the new host is exposed to feeds or foods contaminated
with the disease agent. The purpose of this study was to test whether non-human
primates (cynomologous macaque) are susceptible to the agent of sheep scrapie.
After an incubation period of approximately 10 years a macaque developed
progressive clinical signs suggestive of neurologic disease. Upon postmortem
examination and microscopic examination of tissues, there was a widespread
distribution of lesions consistent with a transmissible spongiform
encephalopathy. This information will have a scientific impact since it is the
first study that demonstrates the transmission of scrapie to a non-human primate
with a close genetic relationship to humans. This information is especially
useful to regulatory officials and those involved with risk assessment of the
potential transmission of animal prion diseases to humans. Technical Abstract:
Classical bovine spongiform encephalopathy (c-BSE) is an animal prion disease
that also causes variant Creutzfeldt-Jakob disease in humans. Over the past
decades, c-BSE's zoonotic potential has been the driving force in establishing
extensive protective measures for animal and human health.
*** In complement to the recent demonstration that humanized mice are
susceptible to scrapie, we report here the first observation of direct
transmission of a natural classical scrapie isolate to a macaque after a 10-year
incubation period. Neuropathologic examination revealed all of the features of a
prion disease: spongiform change, neuronal loss, and accumulation of PrPres
throughout the CNS.
*** This observation strengthens the questioning of the harmlessness of
scrapie to humans, at a time when protective measures for human and animal
health are being dismantled and reduced as c-BSE is considered controlled and
being eradicated.
*** Our results underscore the importance of precautionary and protective
measures and the necessity for long-term experimental transmission studies to
assess the zoonotic potential of other animal prion strains.
***This information will have a scientific impact since it is the first
study that demonstrates the transmission of scrapie to a non-human primate with
a close genetic relationship to humans. This information is especially useful to
regulatory officials and those involved with risk assessment of the potential
transmission of animal prion diseases to humans.
***This observation strengthens the questioning of the harmlessness of
scrapie to humans, at a time when protective measures for human and animal
health are being dismantled and reduced as c-BSE is considered controlled and
being eradicated. Our results underscore the importance of precautionary and
protective measures and the necessity for long-term experimental transmission
studies to assess the zoonotic potential of other animal prion strains.
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
”The occurrence of CWD must be viewed against the contest of the locations
in which it occurred. It was an incidental and unwelcome complication of the
respective wildlife research programmes. Despite it’s subsequent recognition as
a new disease of cervids, therefore justifying direct investigation, no specific
research funding was forthcoming. The USDA veiwed it as a wildlife problem and
consequently not their province!” page 26.
In Confidence - Perceptions of unconventional slow virus diseases of
animals in the USA - APRIL-MAY 1989 - G A H Wells
3. Prof. A. Robertson gave a brief account of BSE. The US approach was to
accord it a very low profile indeed. Dr. A Thiermann showed the picture in the
''Independent'' with cattle being incinerated and thought this was a fanatical
incident to be avoided in the US at all costs. ...
MAD COW DISEASE HAS BEEN IN THE USA FOR DECADES, AND I BELIEVE IT WAS IN
THE USA FIRST, PLEASE SEE ;
Evidence That Transmissible Mink Encephalopathy Results from Feeding
Infected Cattle Over the next 8-10 weeks, approximately 40% of all the adult
mink on the farm died from TME.
snip...
The rancher was a ''dead stock'' feeder using mostly (>95%) downer
or dead dairy cattle...
PL1
Using in vitro prion replication for high sensitive detection of prions and
prionlike proteins and for understanding mechanisms of transmission.
Claudio Soto
Mitchell Center for Alzheimer's diseases and related Brain disorders,
Department of Neurology, University of Texas Medical School at Houston.
Prion and prion-like proteins are misfolded protein aggregates with the
ability to selfpropagate to spread disease between cells, organs and in some
cases across individuals. I n T r a n s m i s s i b l e s p o n g i f o r m
encephalopathies (TSEs), prions are mostly composed by a misfolded form of the
prion protein (PrPSc), which propagates by transmitting its misfolding to the
normal prion protein (PrPC). The availability of a procedure to replicate prions
in the laboratory may be important to study the mechanism of prion and
prion-like spreading and to develop high sensitive detection of small quantities
of misfolded proteins in biological fluids, tissues and environmental samples.
Protein Misfolding Cyclic Amplification (PMCA) is a simple, fast and efficient
methodology to mimic prion replication in the test tube. PMCA is a platform
technology that may enable amplification of any prion-like misfolded protein
aggregating through a seeding/nucleation process. In TSEs, PMCA is able to
detect the equivalent of one single molecule of infectious PrPSc and propagate
prions that maintain high infectivity, strain properties and species
specificity. Using PMCA we have been able to detect PrPSc in blood and urine of
experimentally infected animals and humans affected by vCJD with high
sensitivity and specificity. Recently, we have expanded the principles of PMCA
to amplify amyloid-beta (Aβ) and alphasynuclein (α-syn) aggregates implicated in
Alzheimer's and Parkinson's diseases, respectively. Experiments are ongoing to
study the utility of this technology to detect Aβ and α-syn aggregates in
samples of CSF and blood from patients affected by these diseases.
=========================
***Recently, we have been using PMCA to study the role of environmental
prion contamination on the horizontal spreading of TSEs. These experiments have
focused on the study of the interaction of prions with plants and
environmentally relevant surfaces. Our results show that plants (both leaves and
roots) bind tightly to prions present in brain extracts and excreta (urine and
feces) and retain even small quantities of PrPSc for long periods of time.
Strikingly, ingestion of prioncontaminated leaves and roots produced disease
with a 100% attack rate and an incubation period not substantially longer than
feeding animals directly with scrapie brain homogenate. Furthermore, plants can
uptake prions from contaminated soil and transport them to different parts of
the plant tissue (stem and leaves). Similarly, prions bind tightly to a variety
of environmentally relevant surfaces, including stones, wood, metals, plastic,
glass, cement, etc. Prion contaminated surfaces efficiently transmit prion
disease when these materials were directly injected into the brain of animals
and strikingly when the contaminated surfaces were just placed in the animal
cage. These findings demonstrate that environmental materials can efficiently
bind infectious prions and act as carriers of infectivity, suggesting that they
may play an important role in the horizontal transmission of the disease.
========================
Since its invention 13 years ago, PMCA has helped to answer fundamental
questions of prion propagation and has broad applications in research areas
including the food industry, blood bank safety and human and veterinary disease
diagnosis.
see ;
Wednesday, December 16, 2015
Objects in contact with classical scrapie sheep act as a reservoir for
scrapie transmission
Objects in contact with classical scrapie sheep act as a reservoir for
scrapie transmission
Timm Konold1*, Stephen A. C. Hawkins2, Lisa C. Thurston3, Ben C. Maddison4,
Kevin C. Gough5, Anthony Duarte1 and Hugh A. Simmons1
1 Animal Sciences Unit, Animal and Plant Health Agency Weybridge,
Addlestone, UK, 2 Pathology Department, Animal and Plant Health Agency
Weybridge, Addlestone, UK, 3 Surveillance and Laboratory Services, Animal and
Plant Health Agency Penrith, Penrith, UK, 4 ADAS UK, School of Veterinary
Medicine and Science, University of Nottingham, Sutton Bonington, UK, 5 School
of Veterinary Medicine and Science, University of Nottingham, Sutton Bonington,
UK
Classical scrapie is an environmentally transmissible prion disease of
sheep and goats. Prions can persist and remain potentially infectious in the
environment for many years and thus pose a risk of infecting animals after
re-stocking. In vitro studies using serial protein misfolding cyclic
amplification (sPMCA) have suggested that objects on a scrapie affected sheep
farm could contribute to disease transmission. This in vivo study aimed to
determine the role of field furniture (water troughs, feeding troughs, fencing,
and other objects that sheep may rub against) used by a scrapie-infected sheep
flock as a vector for disease transmission to scrapie-free lambs with the prion
protein genotype VRQ/VRQ, which is associated with high susceptibility to
classical scrapie. When the field furniture was placed in clean accommodation,
sheep became infected when exposed to either a water trough (four out of five)
or to objects used for rubbing (four out of seven). This field furniture had
been used by the scrapie-infected flock 8 weeks earlier and had previously been
shown to harbor scrapie prions by sPMCA. Sheep also became infected (20 out of
23) through exposure to contaminated field furniture placed within pasture not
used by scrapie-infected sheep for 40 months, even though swabs from this
furniture tested negative by PMCA. This infection rate decreased (1 out of 12)
on the same paddock after replacement with clean field furniture. Twelve grazing
sheep exposed to field furniture not in contact with scrapie-infected sheep for
18 months remained scrapie free. The findings of this study highlight the role
of field furniture used by scrapie-infected sheep to act as a reservoir for
disease re-introduction although infectivity declines considerably if the field
furniture has not been in contact with scrapie-infected sheep for several
months. PMCA may not be as sensitive as VRQ/VRQ sheep to test for environmental
contamination.
snip...
Discussion
Classical scrapie is an environmentally transmissible disease because it
has been reported in naĂŻve, supposedly previously unexposed sheep placed in
pastures formerly occupied by scrapie-infected sheep (4, 19, 20). Although the
vector for disease transmission is not known, soil is likely to be an important
reservoir for prions (2) where – based on studies in rodents – prions can adhere
to minerals as a biologically active form (21) and remain infectious for more
than 2 years (22). Similarly, chronic wasting disease (CWD) has re-occurred in
mule deer housed in paddocks used by infected deer 2 years earlier, which was
assumed to be through foraging and soil consumption (23).
Our study suggested that the risk of acquiring scrapie infection was
greater through exposure to contaminated wooden, plastic, and metal surfaces via
water or food troughs, fencing, and hurdles than through grazing. Drinking from
a water trough used by the scrapie flock was sufficient to cause infection in
sheep in a clean building. Exposure to fences and other objects used for rubbing
also led to infection, which supported the hypothesis that skin may be a vector
for disease transmission (9). The risk of these objects to cause infection was
further demonstrated when 87% of 23 sheep presented with PrPSc in lymphoid
tissue after grazing on one of the paddocks, which contained metal hurdles, a
metal lamb creep and a water trough in contact with the scrapie flock up to 8
weeks earlier, whereas no infection had been demonstrated previously in sheep
grazing on this paddock, when equipped with new fencing and field furniture.
When the contaminated furniture and fencing were removed, the infection rate
dropped significantly to 8% of 12 sheep, with soil of the paddock as the most
likely source of infection caused by shedding of prions from the
scrapie-infected sheep in this paddock up to a week earlier.
This study also indicated that the level of contamination of field
furniture sufficient to cause infection was dependent on two factors: stage of
incubation period and time of last use by scrapie-infected sheep. Drinking from
a water trough that had been used by scrapie sheep in the predominantly
pre-clinical phase did not appear to cause infection, whereas infection was
shown in sheep drinking from the water trough used by scrapie sheep in the later
stage of the disease. It is possible that contamination occurred through
shedding of prions in saliva, which may have contaminated the surface of the
water trough and subsequently the water when it was refilled. Contamination
appeared to be sufficient to cause infection only if the trough was in contact
with sheep that included clinical cases. Indeed, there is an increased risk of
bodily fluid infectivity with disease progression in scrapie (24) and CWD (25)
based on PrPSc detection by sPMCA. Although ultraviolet light and heat under
natural conditions do not inactivate prions (26), furniture in contact with the
scrapie flock, which was assumed to be sufficiently contaminated to cause
infection, did not act as vector for disease if not used for 18 months, which
suggest that the weathering process alone was sufficient to inactivate prions.
PrPSc detection by sPMCA is increasingly used as a surrogate for
infectivity measurements by bioassay in sheep or mice. In this reported study,
however, the levels of PrPSc present in the environment were below the limit of
detection of the sPMCA method, yet were still sufficient to cause infection of
in-contact animals. In the present study, the outdoor objects were removed from
the infected flock 8 weeks prior to sampling and were positive by sPMCA at very
low levels (2 out of 37 reactions). As this sPMCA assay also yielded 2 positive
reactions out of 139 in samples from the scrapie-free farm, the sPMCA assay
could not detect PrPSc on any of the objects above the background of the assay.
False positive reactions with sPMCA at a low frequency associated with de novo
formation of infectious prions have been reported (27, 28). This is in contrast
to our previous study where we demonstrated that outdoor objects that had been
in contact with the scrapie-infected flock up to 20 days prior to sampling
harbored PrPSc that was detectable by sPMCA analysis [4 out of 15 reactions
(12)] and was significantly more positive by the assay compared to analogous
samples from the scrapie-free farm. This discrepancy could be due to the use of
a different sPMCA substrate between the studies that may alter the efficiency of
amplification of the environmental PrPSc. In addition, the present study had a
longer timeframe between the objects being in contact with the infected flock
and sampling, which may affect the levels of extractable PrPSc. Alternatively,
there may be potentially patchy contamination of this furniture with PrPSc,
which may have been missed by swabbing. The failure of sPMCA to detect
CWD-associated PrP in saliva from clinically affected deer despite confirmation
of infectivity in saliva-inoculated transgenic mice was associated with as yet
unidentified inhibitors in saliva (29), and it is possible that the sensitivity
of sPMCA is affected by other substances in the tested material. In addition,
sampling of amplifiable PrPSc and subsequent detection by sPMCA may be more
difficult from furniture exposed to weather, which is supported by the
observation that PrPSc was detected by sPMCA more frequently in indoor than
outdoor furniture (12). A recent experimental study has demonstrated that
repeated cycles of drying and wetting of prion-contaminated soil, equivalent to
what is expected under natural weathering conditions, could reduce PMCA
amplification efficiency and extend the incubation period in hamsters inoculated
with soil samples (30). This seems to apply also to this study even though the
reduction in infectivity was more dramatic in the sPMCA assays than in the sheep
model. Sheep were not kept until clinical end-point, which would have enabled us
to compare incubation periods, but the lack of infection in sheep exposed to
furniture that had not been in contact with scrapie sheep for a longer time
period supports the hypothesis that prion degradation and subsequent loss of
infectivity occurs even under natural conditions.
In conclusion, the results in the current study indicate that removal of
furniture that had been in contact with scrapie-infected animals should be
recommended, particularly since cleaning and decontamination may not effectively
remove scrapie infectivity (31), even though infectivity declines considerably
if the pasture and the field furniture have not been in contact with
scrapie-infected sheep for several months. As sPMCA failed to detect PrPSc in
furniture that was subjected to weathering, even though exposure led to
infection in sheep, this method may not always be reliable in predicting the
risk of scrapie infection through environmental contamination. These results
suggest that the VRQ/VRQ sheep model may be more sensitive than sPMCA for the
detection of environmentally associated scrapie, and suggest that extremely low
levels of scrapie contamination are able to cause infection in susceptible sheep
genotypes.
Keywords: classical scrapie, prion, transmissible spongiform
encephalopathy, sheep, field furniture, reservoir, serial protein misfolding
cyclic amplification
Wednesday, December 16, 2015
*** Objects in contact with classical scrapie sheep act as a reservoir for
scrapie transmission ***
Circulation of prions within dust on a scrapie affected farm
Kevin C Gough1, Claire A Baker2, Hugh A Simmons3, Steve A Hawkins3 and Ben
C Maddison2*
Abstract
Prion diseases are fatal neurological disorders that affect humans and
animals. Scrapie of sheep/goats and Chronic Wasting Disease (CWD) of deer/elk
are contagious prion diseases where environmental reservoirs have a direct link
to the transmission of disease. Using protein misfolding cyclic amplification we
demonstrate that scrapie PrPSc can be detected within circulating dusts that are
present on a farm that is naturally contaminated with sheep scrapie. The
presence of infectious scrapie within airborne dusts may represent a possible
route of infection and illustrates the difficulties that may be associated with
the effective decontamination of such scrapie affected premises.
snip...
Discussion
We present biochemical data illustrating the airborne movement of scrapie
containing material within a contaminated farm environment. We were able to
detect scrapie PrPSc within extracts from dusts collected over a 70 day period,
in the absence of any sheep activity. We were also able to detect scrapie PrPSc
within dusts collected within pasture at 30 m but not at 60 m distance away from
the scrapie contaminated buildings, suggesting that the chance of contamination
of pasture by scrapie contaminated dusts decreases with distance from
contaminated farm buildings. PrPSc amplification by sPMCA has been shown to
correlate with infectivity and amplified products have been shown to be
infectious [14,15]. These experiments illustrate the potential for low dose
scrapie infectivity to be present within such samples. We estimate low ng levels
of scrapie positive brain equivalent were deposited per m2 over 70 days, in a
barn previously occupied by sheep affected with scrapie. This movement of dusts
and the accumulation of low levels of scrapie infectivity within this
environment may in part explain previous observations where despite stringent
pen decontamination regimens healthy lambs still became scrapie infected after
apparent exposure from their environment alone [16]. The presence of sPMCA
seeding activity and by inference, infectious prions within dusts, and their
potential for airborne dissemination is highly novel and may have implications
for the spread of scrapie within infected premises. The low level circulation
and accumulation of scrapie prion containing dust material within the farm
environment will likely impede the efficient decontamination of such scrapie
contaminated buildings unless all possible reservoirs of dust are removed.
Scrapie containing dusts could possibly infect animals during feeding and
drinking, and respiratory and conjunctival routes may also be involved. It has
been demonstrated that scrapie can be efficiently transmitted via the nasal
route in sheep [17], as is also the case for CWD in both murine models and in
white tailed deer [18-20].
The sources of dust borne prions are unknown but it seems reasonable to
assume that faecal, urine, skin, parturient material and saliva-derived prions
may contribute to this mobile environmental reservoir of infectivity. This work
highlights a possible transmission route for scrapie within the farm
environment, and this is likely to be paralleled in CWD which shows strong
similarities with scrapie in terms of prion dissemination and disease
transmission. The data indicate that the presence of scrapie prions in dust is
likely to make the control of these diseases a considerable challenge.
Research Project: TRANSMISSION, DIFFERENTIATION, AND PATHOBIOLOGY OF
TRANSMISSIBLE SPONGIFORM ENCEPHALOPATHIES
Title: Scrapie transmits to white-tailed deer by the oral route and has a
molecular profile similar to chronic wasting disease
Authors
item Greenlee, Justin item Moore, S - item Smith, Jodi - item Kunkle,
Robert item West Greenlee, M -
Submitted to: American College of Veterinary Pathologists Meeting
Publication Type: Abstract Only Publication Acceptance Date: August 12, 2015
Publication Date: N/A Technical Abstract: The purpose of this work was to
determine susceptibility of white-tailed deer (WTD) to the agent of sheep
scrapie and to compare the resultant PrPSc to that of the original inoculum and
chronic wasting disease (CWD). We inoculated WTD by a natural route of exposure
(concurrent oral and intranasal (IN); n=5) with a US scrapie isolate. All
scrapie-inoculated deer had evidence of PrPSc accumulation. PrPSc was detected
in lymphoid tissues at preclinical time points, and deer necropsied after 28
months post-inoculation had clinical signs, spongiform encephalopathy, and
widespread distribution of PrPSc in neural and lymphoid tissues. Western
blotting (WB) revealed PrPSc with 2 distinct molecular profiles. WB on cerebral
cortex had a profile similar to the original scrapie inoculum, whereas WB of
brainstem, cerebellum, or lymph nodes revealed PrPSc with a higher profile
resembling CWD. Homogenates with the 2 distinct profiles from WTD with clinical
scrapie were further passaged to mice expressing cervid prion protein and
intranasally to sheep and WTD. In cervidized mice, the two inocula have distinct
incubation times. Sheep inoculated intranasally with WTD derived scrapie
developed disease, but only after inoculation with the inoculum that had a
scrapie-like profile. The WTD study is ongoing, but deer in both inoculation
groups are positive for PrPSc by rectal mucosal biopsy. In summary, this work
demonstrates that WTD are susceptible to the agent of scrapie, two distinct
molecular profiles of PrPSc are present in the tissues of affected deer, and
inoculum of either profile readily passes to deer.
White-tailed Deer are Susceptible to Scrapie by Natural Route of Infection
Jodi D. Smith, Justin J. Greenlee, and Robert A. Kunkle; Virus and Prion
Research Unit, National Animal Disease Center, USDA-ARS
Interspecies transmission studies afford the opportunity to better
understand the potential host range and origins of prion diseases. Previous
experiments demonstrated that white-tailed deer are susceptible to sheep-derived
scrapie by intracranial inoculation. The purpose of this study was to determine
susceptibility of white-tailed deer to scrapie after a natural route of
exposure. Deer (n=5) were inoculated by concurrent oral (30 ml) and intranasal
(1 ml) instillation of a 10% (wt/vol) brain homogenate derived from a sheep
clinically affected with scrapie. Non-inoculated deer were maintained as
negative controls. All deer were observed daily for clinical signs. Deer were
euthanized and necropsied when neurologic disease was evident, and tissues were
examined for abnormal prion protein (PrPSc) by immunohistochemistry (IHC) and
western blot (WB). One animal was euthanized 15 months post-inoculation (MPI)
due to an injury. At that time, examination of obex and lymphoid tissues by IHC
was positive, but WB of obex and colliculus were negative. Remaining deer
developed clinical signs of wasting and mental depression and were necropsied
from 28 to 33 MPI. 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. 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 ;
PO-039: A comparison of scrapie and chronic wasting disease in white-tailed
deer
Justin Greenlee, Jodi Smith, Eric Nicholson US Dept. Agriculture;
Agricultural Research Service, National Animal Disease Center; Ames, IA USA
White-tailed deer are susceptible to the agent of sheep scrapie by
intracerebral inoculation
snip...
It is unlikely that CWD will be eradicated from free-ranging cervids, and
the disease is likely to continue to spread geographically [10]. However, the
potential that white-tailed deer may be susceptible to sheep scrapie by a
natural route presents an additional confounding factor to halting the spread of
CWD. This leads to the additional speculations that
1) infected deer could serve as a reservoir to infect sheep with scrapie
offering challenges to scrapie eradication efforts and
2) CWD spread need not remain geographically confined to current endemic
areas, but could occur anywhere that sheep with scrapie and susceptible cervids
cohabitate.
This work demonstrates for the first time that white-tailed deer are
susceptible to sheep scrapie by intracerebral inoculation with a high attack
rate and that the disease that results has similarities to CWD. These
experiments will be repeated with a more natural route of inoculation to
determine the likelihood of the potential transmission of sheep scrapie to
white-tailed deer. If scrapie were to occur in white-tailed deer, results of
this study indicate that it would be detected as a TSE, but may be difficult to
differentiate from CWD without in-depth biochemical analysis.
2012
PO-039: A comparison of scrapie and chronic wasting disease in white-tailed
deer
Justin Greenlee, Jodi Smith, Eric Nicholson US Dept. Agriculture;
Agricultural Research Service, National Animal Disease Center; Ames, IA USA
snip...
The results of this study suggest that there are many similarities in the
manifestation of CWD and scrapie in WTD 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 similar to 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 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.
White-tailed Deer are Susceptible to Scrapie by Natural Route of Infection
Jodi D. Smith, Justin J. Greenlee, and Robert A. Kunkle; Virus and Prion
Research Unit, National Animal Disease Center, USDA-ARS
Interspecies transmission studies afford the opportunity to better
understand the potential host range and origins of prion diseases. Previous
experiments demonstrated that white-tailed deer are susceptible to sheep-derived
scrapie by intracranial inoculation. The purpose of this study was to determine
susceptibility of white-tailed deer to scrapie after a natural route of
exposure. Deer (n=5) were inoculated by concurrent oral (30 ml) and intranasal
(1 ml) instillation of a 10% (wt/vol) brain homogenate derived from a sheep
clinically affected with scrapie. Non-inoculated deer were maintained as
negative controls. All deer were observed daily for clinical signs. Deer were
euthanized and necropsied when neurologic disease was evident, and tissues were
examined for abnormal prion protein (PrPSc) by immunohistochemistry (IHC) and
western blot (WB). One animal was euthanized 15 months post-inoculation (MPI)
due to an injury. At that time, examination of obex and lymphoid tissues by IHC
was positive, but WB of obex and colliculus were negative. Remaining deer
developed clinical signs of wasting and mental depression and were necropsied
from 28 to 33 MPI. 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. 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 ;
Monday, November 3, 2014
Persistence of ovine scrapie infectivity in a farm environment following
cleaning and decontamination
PPo3-22:
Detection of Environmentally Associated PrPSc on a Farm with Endemic
Scrapie
Ben C. Maddison,1 Claire A. Baker,1 Helen C. Rees,1 Linda A. Terry,2 Leigh
Thorne,2 Susan J. Belworthy2 and Kevin C. Gough3 1ADAS-UK LTD; Department of
Biology; University of Leicester; Leicester, UK; 2Veterinary Laboratories
Agency; Surry, KT UK; 3Department of Veterinary Medicine and Science; University
of Nottingham; Sutton Bonington, Loughborough UK
Key words: scrapie, evironmental persistence, sPMCA
Ovine scrapie shows considerable horizontal transmission, yet the routes of
transmission and specifically the role of fomites in transmission remain poorly
defined. Here we present biochemical data demonstrating that on a
scrapie-affected sheep farm, scrapie prion contamination is widespread. It was
anticipated at the outset that if prions contaminate the environment that they
would be there at extremely low levels, as such the most sensitive method
available for the detection of PrPSc, serial Protein Misfolding Cyclic
Amplification (sPMCA), was used in this study. We investigated the distribution
of environmental scrapie prions by applying ovine sPMCA to samples taken from a
range of surfaces that were accessible to animals and could be collected by use
of a wetted foam swab. Prion was amplified by sPMCA from a number of these
environmental swab samples including those taken from metal, plastic and wooden
surfaces, both in the indoor and outdoor environment. At the time of sampling
there had been no sheep contact with these areas for at least 20 days prior to
sampling indicating that prions persist for at least this duration in the
environment. These data implicate inanimate objects as environmental reservoirs
of prion infectivity which are likely to contribute to disease transmission.
Veterinary Pathology Onlinevet.sagepub.com Published online before print
February 27, 2014, doi: 10.1177/0300985814524798 Veterinary Pathology February
27, 2014 0300985814524798
Lesion Profiling and Subcellular Prion Localization of Cervid Chronic
Wasting Disease in Domestic Cats
D. M. Seelig1⇑ A. V. Nalls1 M. Flasik2 V. Frank1 S. Eaton2 C. K. Mathiason1
E. A. Hoover1 1Department of Microbiology, Immunology, and Pathology, Colorado
State University, Fort Collins, CO, USA 2Department of Biomedical Sciences,
Colorado State University, Fort Collins, CO, USA D. M. Seelig, University of
Minnesota, Department of Veterinary Clinical Sciences, Room 339 VetMedCtrS,
6192A (Campus Delivery Code), 1352 Boyd Ave, St Paul, MN 55108, USA. Email
address: dseelig@umn.edu
Abstract
Chronic wasting disease (CWD) is an efficiently transmitted, fatal, and
progressive prion disease of cervids with an as yet to be fully clarified host
range. While outbred domestic cats (Felis catus) have recently been shown to be
susceptible to experimental CWD infection, the neuropathologic features of the
infection are lacking. Such information is vital to provide diagnostic power in
the event of natural interspecies transmission and insights into host and strain
interactions in interspecies prion infection. Using light microscopy and
immunohistochemistry, we detail the topographic pattern of neural spongiosis
(the “lesion profile”) and the distribution of misfolded prion protein in the
primary and secondary passage of feline CWD (FelCWD). We also evaluated cellular
and subcellular associations between misfolded prion protein (PrPD) and central
nervous system neurons and glial cell populations. From these studies, we (1)
describe the novel neuropathologic profile of FelCWD, which is distinct from
either cervid CWD or feline spongiform encephalopathy (FSE), and (2) provide
evidence of serial passage-associated interspecies prion adaptation. In
addition, we demonstrate through confocal analysis the successful
co-localization of PrPD with neurons, astrocytes, microglia, lysosomes, and
synaptophysin, which, in part, implicates each of these in the neuropathology of
FelCWD. In conclusion, this work illustrates the simultaneous role of both host
and strain in the development of a unique FelCWD neuropathologic profile and
that such a profile can be used to discriminate between FelCWD and FSE.
prion chronic wasting disease immunohistochemistry interspecies cat feline
spongiform encephalopathy transmissible spongiform encephalopathy adaptation
species barrier
Monday, August 8, 2011 Susceptibility of Domestic Cats to CWD Infection
Oral.29: Susceptibility of Domestic Cats to CWD Infection
Amy Nalls, Nicholas J. Haley, Jeanette Hayes-Klug, Kelly Anderson, Davis M.
Seelig, Dan S. Bucy, Susan L. Kraft, Edward A. Hoover and Candace K. Mathiason†
Colorado State University; Fort Collins, CO USA†Presenting author; Email:
ckm@lamar.colostate.edu
Domestic and non-domestic cats have been shown to be susceptible to one
prion disease, feline spongiform encephalopathy (FSE), thought to be transmitted
through consumption of bovine spongiform encephalopathy (BSE) contaminated meat.
Because domestic and free ranging felids scavenge cervid carcasses, including
those in CWD affected areas, we evaluated the susceptibility of domestic cats to
CWD infection experimentally. Groups of n = 5 cats each were inoculated either
intracerebrally (IC) or orally (PO) with CWD deer brain homogenate. Between
40–43 months following IC inoculation, two cats developed mild but progressive
symptoms including weight loss, anorexia, polydipsia, patterned motor behaviors
and ataxia—ultimately mandating euthanasia. Magnetic resonance imaging (MRI) on
the brain of one of these animals (vs. two age-matched controls) performed just
before euthanasia revealed increased ventricular system volume, more prominent
sulci, and T2 hyperintensity deep in the white matter of the frontal hemisphere
and in cortical grey distributed through the brain, likely representing
inflammation or gliosis. PrPRES and widely distributed peri-neuronal vacuoles
were demonstrated in the brains of both animals by immunodetection assays. No
clinical signs of TSE have been detected in the remaining primary passage cats
after 80 months pi. Feline-adapted CWD was sub-passaged into groups (n=4 or 5)
of cats by IC, PO, and IP/SQ routes. Currently, at 22 months pi, all five IC
inoculated cats are demonstrating abnormal behavior including increasing
aggressiveness, pacing, and hyper responsiveness.
*** Two of these cats have developed rear limb ataxia. Although the limited
data from this ongoing study must be considered preliminary, they raise the
potential for cervid-to-feline transmission in nature.
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.
www.landesbioscience.com
PO-081: Chronic wasting disease in the cat— Similarities to feline
spongiform encephalopathy (FSE)
FELINE SPONGIFORM ENCEPHALOPATHY FSE
Wednesday, October 17, 2012
Prion Remains Infectious after Passage through Digestive System of American
Crows (Corvus brachyrhynchos)
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 ;
Chronic Wasting Disease CWD TSE Prion Roundup USA April 1, 2016
*** Needless conflict ***
Nature 485, 279–280 (17 May 2012) doi:10.1038/485279b
Published online 16 May 2012
Terry S. Singeltary Sr. said:
I kindly wish to submit the following please ;
"The fact the Texas cow showed up fairly clearly implied the existence of
other undetected cases," Dr. Paul Brown, former medical director of the National
Institutes of Health's Laboratory for Central Nervous System Studies and an
expert on mad cow-like diseases, told United Press International. "The question
was, 'How many?' and we still can't answer that." Brown, who is preparing a
scientific paper based on the latest two mad cow cases to estimate the maximum
number of infected cows that occurred in the United States, said he has
"absolutely no confidence in USDA tests before one year ago" because of the
agency's reluctance to retest the Texas cow that initially tested positive.
USDA officials finally retested the cow and confirmed it was infected seven
months later, but only at the insistence of the agency's inspector
general.
"Everything they did on the Texas cow makes everything they did before 2005
suspect," Brown said.
Thursday, October 22, 2015
*** Former Ag Secretary Ann Veneman talks women in agriculture and we talk
mad cow disease USDA and what really happened ***
Thursday, January 14, 2016
*** EMERGING ANIMAL DISEASES Actions Needed to Better Position USDA to
Address Future Risks Report to the Chairman, Committee on Energy and Commerce,
House of Representatives December 2015 GAO-16-132
GAO
”The occurrence of CWD must be viewed against the contest of the locations
in which it occurred. It was an incidental and unwelcome complication of the
respective wildlife research programmes. Despite it’s subsequent recognition as
a new disease of cervids, therefore justifying direct investigation, no specific
research funding was forthcoming. The USDA veiwed it as a wildlife problem and
consequently not their province!” page 26.
In Confidence - Perceptions of unconventional slow virus diseases of
animals in the USA - APRIL-MAY 1989 - G A H Wells
3. Prof. A. Robertson gave a brief account of BSE. The US approach was to
accord it a very low profile indeed. Dr. A Thiermann showed the picture in the
''Independent'' with cattle being incinerated and thought this was a fanatical
incident to be avoided in the US at all costs. ...
*** some history on the mule deer in Texas with CWD Trans Pecos area
;
Wednesday, March 18, 2015
Chronic Wasting Disease CWD Confirmed Texas Trans Pecos March 18, 2015
Wednesday, March 25, 2015
Chronic Wasting Disease CWD Cases Confirmed In New Mexico 2013 and 2014
UPDATE 2015
Thursday, May 02, 2013
*** Chronic Wasting Disease (CWD) Texas Important Update on OBEX ONLY
TEXTING
Monday, February 11, 2013
TEXAS CHRONIC WASTING DISEASE CWD Four New Positives Found in Trans Pecos
Tuesday, July 10, 2012
Chronic Wasting Disease Detected in Far West Texas
Monday, March 26, 2012
Texas Prepares for Chronic Wasting Disease CWD Possibility in Far West
Texas
***for anyone interested, here is some history of CWD along the Texas, New
Mexico border, and my attempt to keep up with it...terry
***CWD TEXAS TAHC OLD FILE HISTORY
updated from some of my old files. ...
Subject: CWD SURVEILLANCE STATISTICS TEXAS (total testing figures less
than 50 in two years)
Date: Sun, 25 Aug 2002 21:06:49 –0700
From: "Terry S. Singeltary Sr."
Reply-To: Bovine Spongiform Encephalopathy
To: BSE-L@uni-karlsruhe.de
######## Bovine Spongiform Encephalopathy #########
greetings list members,
here are some figures on CWD testing in TEXAS...TSS
Dear Dr. Singletary,
In Fiscal Year 2001, seven deer from Texas were tested by the National
Veterinary Services Laboratory (NVSL) for CWD (5 fallow deer and 2 white-tailed
deer). In Fiscal Year 2002, seven elk from Texas were tested at NVSL (no deer).
During these two years, an additional six elk and one white-tailed deer were
tested at the Texas Veterinary Medical Diagnostic Laboratory (TVMDL). In Fiscal
Year 2002, four white-tailed deer (free-ranging clinical suspects) and at least
eight other white-tailed deer have been tested at TVMDL. One elk has been tested
at NVSL. All of these animals have been found negative for CWD. Dr. Jerry Cooke
of the Texas Parks and Wildlife Department also has records of 601 clinically
ill white-tailed deer which were necropsied at Texas A&M during the late
1960's and early 1970's, and no spongiform encepalopathies were noted. Thank you
for your consideration.
xxxxxxx
Texas Animal Health Commission
(personal communication...TSS)
Austin 8 news
snip...
"There's about 4 million deer in the state of Texas, and as a resource I
think we need to be doing as much as we can to look for these diseases," said
Doug Humphreys with Texas Parks and Wildlife. "Right now Texas is clear. We
haven't found any, but that doesn't mean we don't look."
With approximately 4 million animals, Texas has the largest population of
white-tailed deer in the nation. In addition, about 19,000 white-tailed deer and
17,000 elk are being held in private facilities. To know if CWD is present in
captive herds, TPWD and Texas Animal Health Commission are working with breeders
to monitor their herds.
How is it spread?
It is not known exactly how CWD is spread. It is believed that the agent
responsible for the disease may be spread both directly (animal to animal
contact) and indirectly (soil or other surface to animal). It is thought that
the most common mode of transmission from an infected animal is via saliva,
feces, and urine.
some surveillance?
beyond the _potential_ methods of transmissions above, why, not a single
word of SRM of various TSE species in feed as a source?
it's a known fact they have been feeding the deer/elk the same stuff as
cows here in USA.
and the oral route has been documented of CWD to mule deer fawns in lab
studies.
not to say that other _potential_ transmission mechanisms are possible,
but why over look the obvious?
TSS
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From: Ken Waldrup, DVM, PhD (host25-207.tahc.state.tx.us)
Subject: Re: CWD SAMPLING TEXAS (but NOT in the obvious place, the NM,
TEXAS border)
Date: December 15, 2003 at 3:43 pm PST
In Reply to: CWD SAMPLING TEXAS (but NOT in the obvious place, the NM,
TEXAS border) posted by TSS on December 12, 2003 at 2:15 pm:
Dear sirs:
With regard to your comment about Texas NOT looking for CWD along the New
Mexico border, it is painfully obvious that you do not know or understand the
natural distribution of mule deer out there or the rights of the land owners in
this state. As of 15 December 2003, a total of 42 deer had been sampled from
what we call "Trans-Pecos", beyond the Pecos River. Mule deer are very widely
dispersed through this area, sometimes at densities of one animal per 6 square
miles. The Texas Parks and Wildlife Department does not have the legal authority
to trepass on private property to collect deer. Some landowners are cooperative.
Some are not. Franklin State Park is at the very tip of Texas, and deer from the
park have been tested (all negative). One of the single largest land owners
along the border is the National Park Service. Deer and elk from the Guadalupe
Peak National Park cannot be collected with federal permission. The sampling
throughout the state is based on the deer populations by eco-region and is
dictated by the availability of funds. I am concerned about your insinuation
that CWD is a human health risk. We are at a stand-off - you have no proof that
it is and I have no definitive proof that it isn't. However I would say that the
inferred evidence from Colorado, Wyoming and Wisconsin suggests that CWD is not
a human health concern (i.e. no evidence of an increased incidence of human
brain disorders within the CWD "endemic" areas of these states). From my
professional interactions with the Texas Parks and Wildlife Department, I can
definitely say that they want to do a thorough and sound survey throughout the
state, not willy-nilly "look here, look there". There are limitations of
manpower, finances and, in some places, deer populations. I would congratulate
TPWD for doing the best job with the limitations at hand rather than trying to
browbeat them when you obviously do not understand the ecology of West Texas.
Thank you for your consideration.
======================
From: TSS (216-119-139-126.ipset19.wt.net)
Subject: Re: CWD SAMPLING TEXAS (but NOT in the obvious place, the NM,
TEXAS border)
Date: December 16, 2003 at 11:03 am PST
In Reply to: Re: CWD SAMPLING TEXAS (but NOT in the obvious place, the NM,
TEXAS border) posted by Ken Waldrup, DVM, PhD on December 15, 2003 at 3:43 pm:
HEllo Dr. Waldrup,
thank you for your comments and time to come to this board.
Ken Waldrup, DVM, PhD states;
> it is painfully obvious that you do not know or understand the
natural distribution of mule deer out there or the rights of the land owners in
this state...
TSS states;
I am concerned about all deer/elk not just mule deer, and the rights of
land owners (in the case with human/animal TSEs) well i am not sure of the
correct terminology, but when the States deer/elk/cattle/sheep/humans are at
risk, there should be no rights for land owners in this case. the state should
have the right to test those animals. there are too many folks out there that
are just plain ignorant about this agent. with an agent such as this, you cannot
let landowners (and i am one) dictate human/animal health, especially when you
cannot regulate the movement of such animals...
Ken Waldrup, DVM, PhD states;
> Deer and elk from the Guadalupe Peak National Park cannot be
collected with federal permission.
TSS states;
I do not understand this? so there is no recourse of action even if every
deer/elk was contaminated with CWD in this area (hypothetical)?
Ken Waldrup, DVM, PhD states;
> I am concerned about your insinuation that CWD is a human health
risk. We are at a stand-off - you have no proof that it is and I have no
definitive proof that it isn't. However I would say that the inferred evidence
from Colorado, Wyoming and Wisconsin suggests that CWD is not a human health
concern (i.e. no evidence of an increased incidence of human brain disorders
within the CWD "endemic" areas of these states)...
TSS states;
NEXT, let's have a look at the overall distribution of CWD in Free-Ranging
Cervids and see where the CWD cluster in NM WSMR borders TEXAS;
Current Distribution of Chronic Wasting Disease in Free-Ranging Cervids
NOW, the MAP of the Exoregion where the samples were taken to test for
CWD;
CWD SURVEILLANCE SAMPLE SUBMISSIONS TEXAS
Ecoregions of TEXAS
IF you look at the area around the NM WSMR where the CWD cluster was and
where it borders TEXAS, that ecoregion is called Trans Pecos region. Seems if my
Geography and my Ciphering is correct ;-) that region only tested 55% of it's
goal. THE most important area on the MAP and they only test some 96 samples,
this in an area that has found some 7 positive animals? NOW if we look at the
only other border where these deer from NM could cross the border into TEXAS,
this area is called the High Plains ecoregion, and again, we find that the
sampling for CWD was pathetic. HERE we find that only 9% of it's goal of CWD
sampling was met, only 16 samples were tested from some 175 that were suppose to
be sampled.
AS i said before;
> SADLY, they have not tested enough from the total population to
> know if CWD is in Texas or not.
BUT now, I will go one step further and state categorically that they are
not trying to find it. just the opposite it seems, they are waiting for CWD to
find them, as with BSE/TSE in cattle, and it will eventually...
snip...end...TSS
===============================
2005
SEE MAP OF CWD ON THE BORDER OF NEW MEXICO VERY CLOSE TO TEXAS ;
NO update on CWD testing in Texas, New Mexico that i could find. I have
inquired about it though, no reply yet...
-------- Original Message --------
Subject: CWD testing to date TEXAS ?
Date: Mon, 09 May 2005 12:26:20 –0500
From: "Terry S. Singeltary Sr."
To: kristen.everett@tpwd.state.tx.us
Hello Mrs. Everett,
I am most curious about the current status on CWD testing in Texas. could
you please tell me what the current and past testing figures are to date and
what geographical locations these tests have been in. good bust on the illegal
deer trapping case. keep up the good work there.........
thank you, with kindest regards,
Terry S. Singeltary Sr. P.O. Box 42 Bacliff, Texas USA 77518
-------- Original Message --------
Subject: CWD testing in New Mexico
Date: Mon, 09 May 2005 14:39:18 –0500
From: "Terry S. Singeltary Sr."
To: ispa@state.nm.us
Greetings,
I am most curious of the current and past CWD testing in New Mexico, and
there geographical locations...
thank you,
Terry S. Singeltary SR. CJD Watch
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2006
----- Original Message -----
From: "Terry S. Singeltary Sr." flounder9@VERIZON.NET
To: BSE-L@aegee.org
Sent: Saturday, December 23, 2006 1:47 PM
Subject: CWD in New Mexico 35 MILES FROM TEXAS BORDER and low testing
sampling figures -- what gives TAHC ???
Subject: CWD in New Mexico 35 MILES FROM TEXAS BORDER and low testing
sampling figures -- what gives TAHC ???
Date: December 23, 2006 at 11:25 am PST
Greetings BSE-L members,
i never know if i am going crazy or just more of the same BSe. several
years ago i brought up the fact to the TAHC that CWD was literally at the Texas
borders and that the sample size for cwd testing was no where near enough in the
location of that zone bordering NM. well, i just wrote them another letter
questioning this again on Dec. 14, 2006 (see below) and showed them two
different pdf maps, one referencing this url, which both worked just fine then.
since then, i have NOT received a letter from them answering my question, and
the url for the map i used as reference is no longer working? i had reference
this map several times from the hunter-kill cwd sampling as of 31 August 2005
pdf which NO longer works now??? but here are those figures for that zone
bordering NM, for those that were questioning the url. the testing samples
elsewhere across Texas where much much more than that figure in the zone
bordering NM where CWD has been documented bordering TEXAS, near the White Sands
Missile Range. SO, why was the Texas hunter-kill cwd sampling as of 31 August
2005 document removed from the internet??? you know, this reminds me of the
infamous TEXAS MAD COW that i documented some 7 or 8 months before USDA et al
documented it, when the TAHC accidentally started ramping up for the
announcement on there web site, then removed it (see history at bottom). i am
not screaming conspiracy here, but confusious is confused again on the ciphering
there using for geographical distribution of cwd tissue sample size survey, IF
they are serious about finding CWD in TEXAS. common sense would tell you if cwd
is 35 miles from the border, you would not run across state and have your larger
samples there, and least samples 35 miles from where is what
found..........daaa..........TSS
THEN NOTICE CWD sample along that border in TEXAS, Three Year Summary of
Hunter-Kill CWD sampling as of 31 August 2005 of only 191 samples, then compare
to the other sample locations ;
TPWD has been conducting surveys of hunter-kill animals since 2002 and has
collected more than 7300 samples (as of 31 August 2005). In total, there have
been over 9400 samples, both hunter-kill and private samples, tested in Texas to
date, and no positives have been found.
SO, out of a total of 9,400 samples taken for CWD surveillance in TEXAS
since 2002 of both hunter-kill and private kill, ONLY 191 samples have been
taken in the most likely place one would find CWD i.e. the border where CWD has
been documented at TEXAS and New Mexico
latest map NM cwd old data
CWD in New Mexico ;
What is the Department doing to prevent the spread of CWD?
Chronic wasting disease (CWD) was recently detected in a mule deer from
Unit 34. Until 2005, CWD had only been found in Unit 19. With this discovery,
the Department will increase its surveillance of deer and elk harvested in Units
29, 30 and 34.
Lymph nodes and/or brain stems from every harvested deer and brain stems
from all elk taken in Unit 34 will be sampled.
snip...
CWD SURVEILLANCE TEXAS
SNIP...SEE FULL TEXT ;
2011 – 2012
Friday, October 28, 2011
CWD Herd Monitoring Program to be Enforced Jan. 2012 TEXAS
Greetings TAHC et al,
A kind greetings from Bacliff, Texas.
In reply to ;
Texas Animal Health Commission (TAHC) Announcement October 27, 2011
I kindly submit the following ;
***for anyone interested, here is some history of CWD along the Texas, New
Mexico border, and my attempt to keep up with it...terry
snip...
see history CWD Texas, New Mexico Border ;
Monday, March 26, 2012
3 CASES OF CWD FOUND NEW MEXICO MULE DEER SEVERAL MILES FROM TEXAS BORDER
Sunday, October 04, 2009
CWD NEW MEXICO SPREADING SOUTH TO TEXAS 2009 2009 Summary of Chronic
Wasting Disease in New Mexico New Mexico Department of Game and Fish
Chronic Wasting Disease CWD TSE Prion Roundup USA April 1, 2016
Terry S. Singeltary Sr.
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