Tuesday, August 11, 2015
August 7, 2015
Why Has the Federal Government Cut Funding for Chronic Wasting Disease
Research?
by Craig Dougherty 13
Photograph by USFWS
Ask any deer biologist to list the top threats to the future of deer and
deer hunting and you can be almost certain that Chronic Wasting Disease (CWD)
will be somewhere near the top. CWD is the always-fatal deer disease that has
been steadily spreading across the country. Twenty-two states and two provinces
are now reporting outbreaks of chronic wasting disease. In some states, like New
York, it is but a blip on the radar. In other states, like Wisconsin, it is
leaving an ever-growing and very large footprint. Small blip or large footprint,
the threat of CWD sends chills down the spine of professional deer managers. So
why has the federal government cut funding to fight this disease?
*2012 and 2013 numbers are estimates as no amount was specifically
identified for CWD. 2015 total is aslo an estimate. Data is from Bryan Richards,
USGS.
Bryan Richards, Emerging Disease Coordinator at the USGS National Wildlife
Center, offered this perspective on CWD research: “With the outbreak of CWD in
Wisconsin, the USDA declared CWD a national emergency. In 2002 Congress began to
appropriate large amounts of monies to states for research. At first we were
worried that CWD would spread to humans, so we spent money on humans, and then
we shifted our attention to cattle. The US government was appropriating over $18
million per year in the early 2000s for research. Now we are seeing
appropriations in the range of $1 million to $3 million per year for CWD. With
humans and cattle no longer a concern, the funding has all but disappeared.”
The other experts and researchers I spoke to did not know of any other
major federal funding sources for CWD research. They said it was now mostly up
to the state budgets to fund CWD prevention and research.
Yet chronic wasting disease continues to spread, and little by little
consume the backbone of the hunting industry (i.e. whitetail deer). “It’s as
though we have CWD fatigue,” said Richards. But the problem persists, and if
anything, it’s getting worse.
Dr. David Clausen, a veterinarian, former Chair of the Wisconsin Department
of Natural Resources Board and well-respected CWD expert recently gave a
presentation that pointed out that the number of deer tested for CWD in
Wisconsin has declined drastically even though CWD has increased exponentially.
He cites budgetary reasons for the decline. But even more alarming was his
contention that the worst may lie just ahead. He cited recent research from
Colorado State University, which indicates that plants will take up prions from
infected earth, (where prions can live almost indefinitely) and now CWD prions
are found to bind on grains and other plants. As far as research goes, according
to Clausen, some excellent institutions are still doing research but, “as the
science of CWD continues to evolve. It raises more questions than it answers and
points to the need for more research.”
The Great Unknown
I recently did some research on how states are attempting to control the
spread of CWD. For the most part, they are trying to isolate and eliminate known
carriers of CWD. They have instituted all kinds of restrictions, which appear
primarily preventative in nature. And who can blame them? Who among them wants
to be the one known to ignore the threat of CWD? The deeper I dug into the
issue, the more I learned about what we know and more to the point, what we
think we know about the disease. Now I’m the one with chills running down my
spine. State agencies are making all kinds of decisions on best guesses and and
leaps of faith. Even the Chronic Wasting Alliance is forced to admit how little
we actually know: “It is not completely understood how CWD is spread.”
This has lead to a standoff of sorts between the various factions of the
deer community. I made a list of what the best research scientists in the
country believe we actually know about CWD and compared it to a list of what we
sort of know about CWD. The sort-of-know list was a whole lot longer. That’s
right, all things considered we don’t know all that much about CWD.
The more I dug, the madder I got. Not because we don’t know all that much
about CWD, but it almost looks like we have given up figuring this thing out.
Or, at least the federal government has given up on it. If we are going to have
deer to hunt 50 years from now, we need some answers and we need them fast.
Answers come from good research and research takes both time and money.
Science moves slowly and by all accounts this is tough science. But, it is
also science that is critical to our deer hunting future. Take a look at the
graph above. Congress channeled CWD funds through the USDA. Experts are calling
for increased CWD research but policy makers and politicians continue to ignore
their calls. Funds for CWD research averaged a little over $18.5 million from
2004-2006 then started to steadily drop. They are now hovering around $2.0
million (2012 – 2014).
Where has our federal government gone? Has it pulled the plug on the
disease that many believe has the potential to all but wipe out our deer herds?
As someone who loves whitetail deer, I think that federal funding for CWD
research is not something that we can afford to cut. Maybe it’s time that
hunters start demanding that our government takes up the battle against CWD once
again.
>>> Why Has the Federal Government Cut Funding for Chronic Wasting
Disease Research? <<<
same reason with all the other TSE prion disease in all the other species
and humans in the USA, they have lost control of this slow and long incubating
disease, which once clinical, is 100 % fatal, and will not admit it due to the
many industries and lies there from it will curtail, from the dead and dying.
for something they say is not here, why fund it then. don’t believe me, just
think back to asbestos and tobacco. just saying.
>>> Bryan Richards, emerging disease coordinator at the USGS
National Wildlife Center, suggested that "with humans and cattle no longer a
concern, the funding has all but disappeared." <<<
LOL...with sad tears in my eyes, if they only knew.
who gives a damn about the truth right $$$
what is the truth anyway, or does anyone care anymore.
mom dod 12/14/97 confirmed hvCJD...just made a promise to mom, never
forget, and never let them forget. ...carry on///
20097 Section Contents Menu Recalls, Market Withdrawals, & Safety
Alerts8
Archive for Recalls, Market Withdrawals & Safety Alerts9 200910 Recall
-- Firm Press Release .
Exotic Meats USA Announces Urgent Statewide Recall of Elk Tenderloin
Because It May Contain Meat Derived From An Elk Confirmed To Have Chronic
Wasting Disease
Contact: Exotic Meats USA 1-800-680-4375
FOR IMMEDIATE RELEASE -- February 9, 2009 -- Exotic Meats USA of San
Antonio, TX is initiating a voluntary recall of Elk Tenderloin because it may
contain meat derived from an elk confirmed to have Chronic Wasting Disease
(CWD). The meat with production dates of December 29, 30 and 31, 2008 was
purchased from Sierra Meat Company in Reno, NV. The infected elk came from Elk
Farm LLC in Pine Island, MN and was among animals slaughtered and processed at
USDA facility Noah’s Ark Processors LLC.
Chronic Wasting Disease (CWD) is a fatal brain and nervous system disease
found in elk and deer. The disease is caused by an abnormally shaped protein
called a prion, which can damage the brain and nerves of animals in the deer
family. Currently, it is believed that the prion responsible for causing CWD in
deer and elk is not capable of infecting humans who eat deer or elk contaminated
with the prion, but the observation of animal-to-human transmission of other
prion-mediated diseases, such as bovine spongiform encephalopathy (BSE), has
raised a theoretical concern regarding the transmission of CWD from deer or elk
to humans. At the present time, FDA believes the risk of becoming ill from
eating CWD-positive elk or deer meat is remote. However, FDA strongly advises
consumers to return the product to the place of purchase, rather than disposing
of it themselves, due to environmental concerns.
Thursday, May 26, 2011
Travel History, Hunting, and Venison Consumption Related to Prion Disease
Exposure, 2006-2007 FoodNet Population Survey Journal of the American Dietetic
Association Volume 111, Issue 6 , Pages 858-863, June 2011.
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 ;
==============================
*** 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.
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
Chronic wasting disease (CWD) is a widespread and expanding prion disease
in free-ranging and captive cervid species in North America. The zoonotic
potential of CWD prions is a serious public health concern. Current literature
generated with in vitro methods and in vivo animal models (transgenic mice,
macaques and squirrel monkeys) reports conflicting results. The susceptibility
of human CNS and peripheral organs to CWD prions remains largely unresolved. In
our earlier bioassay experiments using several humanized transgenic mouse lines,
we detected protease-resistant PrPSc in the spleen of two out of 140 mice that
were intracerebrally inoculated with natural CWD isolates, but PrPSc was not
detected in the brain of the same mice. Secondary passages with such
PrPSc-positive CWD-inoculated humanized mouse spleen tissues led to efficient
prion transmission with clear clinical and pathological signs in both humanized
and cervidized transgenic mice. Furthermore, a recent bioassay with natural CWD
isolates in a new humanized transgenic mouse line led to clinical prion
infection in 2 out of 20 mice.
*** 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
***This insinuates that, at the level of protein: protein interactions, the
barrier preventing transmission of CWD to humans is less robust than previously
estimated.
================
P.157: Uptake of prions into plants
Christopher Johnson1, Christina Carlson1, Matthew Keating1,2, Nicole
Gibbs1, Haeyoon Chang1, Jamie Wiepz1, and Joel Pedersen1 1USGS National Wildlife
Health Center; Madison, WI USA; 2University of Wisconsin - Madison; Madison, WI
USA
***Our results suggest that prions can be taken up by plants and that
contaminated plants may represent a previously unrecognized risk of human,
domestic species and wildlife exposure to prions.
===========
CWD TO BOVINE
*** P.126: Successful transmission of chronic wasting disease (CWD) into
mice over-expressing bovine prion protein (TgSB3985)
Larisa Cervenakova,1 Christina J Sigurdson,2 Pedro Piccardo,3 Oksana
Yakovleva,1 Irina Vasilyeva,1 Jorge de Castro,1 Paula Saá,1 and Anton Cervenak1
1American Red Cross, Holland Laboratory; Rockville, MD USA; 2University of
California; San Diego, CA USA; 3Lab TSE/OBRR /CBER/FDA; Rockville, MD USA
Keywords: chronic wasting disease, transmission, transgenic mouse, bovine
prion protein
Background. CWD is a disease affecting wild and farmraised cervids in North
America. Epidemiological studies provide no evidence of CWD transmission to
humans. Multiple attempts have failed to infect transgenic mice expressing human
PRNP gene with CWD. The extremely low efficiency of PrPCWD to convert normal
human PrPC in vitro provides additional evidence that transmission of CWD to
humans cannot be easily achieved. However, a concern about the risk of CWD
transmission to humans still exists. This study aimed to establish and
characterize an experimental model of CWD in TgSB3985 mice with the following
attempt of transmission to TgHu mice.
Materials and Methods. TgSB3985 mice and wild-type FVB/ NCrl mice were
intracranially injected with 1% brain homogenate from a CWD-infected Tga20 mouse
(CWD/Tga20). TgSB3985 and TgRM (over-expressing human PrP) were similarly
injected with 5% brain homogenates from CWD-infected white-tailed deer (CWD/WTD)
or elk (CWD/Elk). Animals were observed for clinical signs of neurological
disease and were euthanized when moribund. Brains and spleens were removed from
all mice for PrPCWD detection by Western blotting (WB). A histological analysis
of brains from selected animals was performed: brains were scored for the
severity of spongiform change, astrogliosis, and PrPCWD deposition in ten brain
regions.
Results. Clinical presentation was consistent with TSE. More than 90% of
TgSB3985 and wild-type mice infected with CWD/Tga20, tested positive for PrPres
in the brain but only mice in the latter group carried PrPCWD in their spleens.
We found evidence for co-existence or divergence of two CWD/ Tga20 strains based
on biochemical and histological profiles. In TgSB3985 mice infected with CWD-elk
or CWD-WTD, no animals tested positive for PrPCWD in the brain or in the spleen
by WB. However, on neuropathological examination we found presence of amyloid
plaques that stained positive for PrPCWD in three CWD/WTD- and two
CWD/Elk-infected TgSB3985 mice. The neuropathologic profiles in CWD/WTD- and
CWD/Elkinfected mice were similar but unique as compared to profiles of BSE,
BSE-H or CWD/Tg20 agents propagated in TgSB3985 mice. None of CWD-infected TgRM
mice tested positive for PrPCWD by WB or by immunohistochemical detection.
Conclusions. To our knowledge, this is the first established experimental
model of CWD in TgSB3985. We found evidence for co-existence or divergence of
two CWD strains adapted to Tga20 mice and their replication in TgSB3985 mice.
Finally, we observed phenotypic differences between cervid-derived CWD and
CWD/Tg20 strains upon propagation in TgSB3985 mice. Further studies are underway
to characterize these strains.
TSS
UPDATED CORRESPONDENCE FROM AUTHORS OF THIS STUDY I.E. COLBY, PRUSINER ET
AL, ABOUT MY CONCERNS OF THE DISCREPANCY BETWEEN THEIR FIGURES AND MY FIGURES OF
THE STUDIES ON CWD TRANSMISSION TO CATTLE ;
CWD to cattle figures CORRECTION
Greetings,
I believe the statement and quote below is incorrect ;
"CWD has been transmitted to cattle after intracerebral inoculation,
although the infection rate was low (4 of 13 animals [Hamir et al. 2001]). This
finding raised concerns that CWD prions might be transmitted to cattle grazing
in contaminated pastures."
Please see ;
Within 26 months post inoculation, 12 inoculated animals had lost weight,
revealed abnormal clinical signs, and were euthanatized. Laboratory tests
revealed the presence of a unique pattern of the disease agent in tissues of
these animals. These findings demonstrate that when CWD is directly inoculated
into the brain of cattle, 86% of inoculated cattle develop clinical signs of the
disease.
" although the infection rate was low (4 of 13 animals [Hamir et al.
2001]). "
shouldn't this be corrected, 86% is NOT a low rate. ...
kindest regards,
Terry S. Singeltary Sr. P.O. Box 42 Bacliff, Texas USA 77518
Thank you!
Thanks so much for your updates/comments. We intend to publish as rapidly
as possible all updates/comments that contribute substantially to the topic
under discussion.
re-Prions David W. Colby1,* and Stanley B. Prusiner1,2 + Author
Affiliations
1Institute for Neurodegenerative Diseases, University of California, San
Francisco, San Francisco, California 94143 2Department of Neurology, University
of California, San Francisco, San Francisco, California 94143 Correspondence:
stanley@ind.ucsf.edu
Mule deer, white-tailed deer, and elk have been reported to develop CWD. As
the only prion disease identified in free-ranging animals, CWD appears to be far
more communicable than other forms of prion disease. CWD was first described in
1967 and was reported to be a spongiform encephalopathy in 1978 on the basis of
histopathology of the brain. Originally detected in the American West, CWD has
spread across much of North America and has been reported also in South Korea.
In captive populations, up to 90% of mule deer have been reported to be positive
for prions (Williams and Young 1980). The incidence of CWD in cervids living in
the wild has been estimated to be as high as 15% (Miller et al. 2000). The
development of transgenic (Tg) mice expressing cervid PrP, and thus susceptible
to CWD, has enhanced detection of CWD and the estimation of prion titers
(Browning et al. 2004; Tamgüney et al. 2006). Shedding of prions in the feces,
even in presymptomatic deer, has been identified as a likely source of infection
for these grazing animals (Williams and Miller 2002; Tamgüney et al. 2009b). CWD
has been transmitted to cattle after intracerebral inoculation, although the
infection rate was low (4 of 13 animals [Hamir et al. 2001]). This finding
raised concerns that CWD prions might be transmitted to cattle grazing in
contaminated pastures.
snip...
----- Original Message -----
From: David Colby To: flounder9@verizon.net
Cc: stanley@XXXXXXXX
Sent: Tuesday, March 01, 2011 8:25 AM
Subject: Re: FW: re-Prions David W. Colby1,* and Stanley B. Prusiner1,2 +
Author Affiliations
Dear Terry Singeltary,
Thank you for your correspondence regarding the review article Stanley
Prusiner and I recently wrote for Cold Spring Harbor Perspectives. Dr. Prusiner
asked that I reply to your message due to his busy schedule. We agree that the
transmission of CWD prions to beef livestock would be a troubling development
and assessing that risk is important. In our article, we cite a peer-reviewed
publication reporting confirmed cases of laboratory transmission based on
stringent criteria. The less stringent criteria for transmission described in
the abstract you refer to lead to the discrepancy between your numbers and ours
and thus the interpretation of the transmission rate. We stand by our assessment
of the literature--namely that the transmission rate of CWD to bovines appears
relatively low, but we recognize that even a low transmission rate could have
important implications for public health and we thank you for bringing attention
to this matter. Warm Regards, David Colby -- David Colby, PhDAssistant Professor
Department of Chemical Engineering University of Delaware
===========END...TSS==============
SNIP...SEE FULL TEXT ;
UPDATED DATA ON 2ND CWD STRAIN Wednesday, September 08, 2010 CWD PRION
CONGRESS SEPTEMBER 8-11 2010
Sunday, August 19, 2012
Susceptibility of cattle to the agent of chronic wasting disease from elk
after intracranial inoculation 2012
Research Project: TRANSMISSION, DIFFERENTIATION, AND PATHOBIOLOGY OF
TRANSMISSIBLE SPONGIFORM ENCEPHALOPATHIES Location: Virus and Prion Research
Unit
Thursday, November 21, 2013
*** Assessing the susceptibility of transgenic mice over-expressing deer
prion protein to bovine spongiform encephalopathy
The present study was designed to assess the susceptibility of the
prototypic mouse line, Tg(CerPrP)1536+/- to bovine spongiform encephalopathy
(BSE) prions, which have the ability to overcome species barriers.
Tg(CerPrP)1536+/- mice challenged with red deer-adapted BSE resulted in a
90-100% attack rates, BSE from cattle failed to transmit, indicating agent
adaptation in the deer.
Thus far, among domestic animals, CWDmd has been transmitted by the
intracerebral route to a goat18 and cattle.5–7 The present findings demonstrate
that it is also possible to transmit CWDmd agent to sheep via the intracerebral
route.
Preliminary studies (Hamir et al., unpublished data, 2006) of intracerebral
inoculation of CWD from white-tailed deer into cattle suggests that this source
is much more efficient at causing disease (as indicated by the attack rate) than
CWDmd.
these cattle ranchers supporting these shooting pens, if there are any,
could be in terrible shape if a strain of cwd was to jump to cattle...just
saying.
Title: Transmission of Chronic Wasting Disease of Mule Deer to Suffolk
Sheep Following Intracerebral Inoculation
Authors
item Hamir, Amirali item Kunkle, Robert item Cutlip, Randall - ARS RETIRED
item Miller, Janice - ARS RETIRED item Williams, Elizabeth - UNIVERSITY OF
WYOMING item Richt, Juergen
Submitted to: Conference Research Workers Disease Meeting Publication Type:
Abstract Only Publication Acceptance Date: December 3, 2006 Publication Date:
December 3, 2006 Citation: Hamir, A.N., Kunkle, R.A., Cutlip, R.C., Miller,
J.M., Williams, E.S., Richt, J.A. 2006. Transmission of chronic wasting disease
of mule deer to Suffolk sheep following intracerebral inoculation [abstract].
Conference of Research Workers in Animal Diseases 87th Annual Meeting. Paper No.
P34. p. 108.
Technical Abstract: To determine the transmissibility of chronic wasting
disease (CWD) to sheep, 8 Suffolk lambs of various prion protein (PRNP) genotype
(4 ARQ/ARR, 3 ARQ/ARQ, 1 ARQ/VRQ at codons 136, 154 and 171, respectively) were
inoculated intracerebrally with brain suspension from mule deer with CWD
(CWD**md). Two other lambs were kept as non inoculated controls. Within 36
months post inoculation (MPI), 2 inoculated animals became sick and were
euthanized. Only 1 sheep (euthanized at 35 MPI) showed clinical signs that were
consistent with those described for scrapie. Microscopic lesions of spongiform
encephalopathy (SE) were only seen in this sheep and its tissues were positive
for the abnormal prion protein (PrP**res) by immunohistochemistry and Western
blot. Three other inoculated sheep were euthanized (36 to 60 MPI) because of
conditions unrelated to TSE. The 3 remaining inoculated sheep and the 2 control
sheep were non clinical at the termination of the study (72 MPI) and were
euthanized. One of the 3 remaining inoculated sheep revealed SE and its tissues
were positive for PrP**res. The sheep with clinical prion disease (euthanized at
35 MPI) was of the heterozygous genotype (ARQ/VRQ) and the sheep with the sub
clinical disease (euthanized at 72 MPI) was of the homozygous ARQ/ARQ genotype.
These findings demonstrate that transmission of the CWD**md agent to sheep via
the intracerebral route is possible. Interestingly, the host genotype may play a
significant part in successful transmission and incubation period of CWD**md.
Last Modified: 11/6/2014
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 soon as possible for the following
reasons...
======
In the USA, under the Food and Drug Administrations 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.
======
31 Jan 2015 at 20:14 GMT
*** Ruminant feed ban for cervids in the United States? ***
Singeltary et al
31 Jan 2015 at 20:14 GMT
*** The association between venison eating and risk of CJD shows similar
pattern, with regular venison eating associated with a 9 FOLD INCREASE IN RISK
OF CJD (p = 0.04).
CREUTZFELDT JAKOB DISEASE SURVEILLANCE IN THE UNITED KINGDOM THIRD ANNUAL
REPORT AUGUST 1994
Consumption of venison and veal was much less widespread among both cases
and controls. For both of these meats there was evidence of a trend with
increasing frequency of consumption being associated with increasing risk of
CJD. (not nvCJD, but sporadic CJD...tss) These associations were largely
unchanged when attention was restricted to pairs with data obtained from
relatives. ...
Table 9 presents the results of an analysis of these data.
There is STRONG evidence of an association between ‘’regular’’ veal eating
and risk of CJD (p = .0.01).
Individuals reported to eat veal on average at least once a year appear to
be at 13 TIMES THE RISK of individuals who have never eaten veal.
There is, however, a very wide confidence interval around this estimate.
There is no strong evidence that eating veal less than once per year is
associated with increased risk of CJD (p = 0.51).
*** The association between venison eating and risk of CJD shows similar
pattern, with regular venison eating associated with a 9 FOLD INCREASE IN RISK
OF CJD (p = 0.04).
There is some evidence that risk of CJD INCREASES WITH INCREASING FREQUENCY
OF LAMB EATING (p = 0.02).
The evidence for such an association between beef eating and CJD is weaker
(p = 0.14). When only controls for whom a relative was interviewed are included,
this evidence becomes a little STRONGER (p = 0.08).
snip...
It was found that when veal was included in the model with another
exposure, the association between veal and CJD remained statistically
significant (p = < 0.05 for all exposures), while the other exposures ceased
to be statistically significant (p = > 0.05).
snip...
In conclusion, an analysis of dietary histories revealed statistical
associations between various meats/animal products and INCREASED RISK OF CJD.
When some account was taken of possible confounding, the association between
VEAL EATING AND RISK OF CJD EMERGED AS THE STRONGEST OF THESE ASSOCIATIONS
STATISTICALLY. ...
snip...
In the study in the USA, a range of foodstuffs were associated with an
increased risk of CJD, including liver consumption which was associated with an
apparent SIX-FOLD INCREASE IN THE RISK OF CJD. By comparing the data from 3
studies in relation to this particular dietary factor, the risk of liver
consumption became non-significant with an odds ratio of 1.2 (PERSONAL
COMMUNICATION, PROFESSOR A. HOFMAN. ERASMUS UNIVERSITY, ROTTERDAM). (???...TSS)
snip...see full report ;
Saturday, May 30, 2015
PRION 2015 ORAL AND POSTER CONGRESSIONAL ABSTRACTS
***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.
HIGHEST INFECTION RATE ON SEVERAL CWD CONFIRMED CAPTIVES
CHRONIC WASTING DISEASE CWD WISCONSIN Almond Deer (Buckhorn Flats) Farm
Update DECEMBER 2011
The CWD infection rate was nearly 80%, the highest ever in a North American
captive herd.
RECOMMENDATION: That the Board approve the purchase of 80 acres of land for
$465,000 for the Statewide Wildlife Habitat Program in Portage County and
approve the restrictions on public use of the site.
SUMMARY:
For Immediate Release Thursday, October 2, 2014
Dustin Vande Hoef 515/281-3375 or 515/326-1616 (cell) or
Dustin.VandeHoef@IowaAgriculture.gov
*** TEST RESULTS FROM CAPTIVE DEER HERD WITH CHRONIC WASTING DISEASE
RELEASED 79.8 percent of the deer tested positive for the disease
DES MOINES – The Iowa Department of Agriculture and Land Stewardship today
announced that the test results from the depopulation of a quarantined captive
deer herd in north-central Iowa showed that 284 of the 356 deer, or 79.8% of the
herd, tested positive for Chronic Wasting Disease (CWD).
*** see history of this CWD blunder here ;
On June 5, 2013, DNR conducted a fence inspection, after gaining approval
from surrounding landowners, and confirmed that the fenced had been cut or
removed in at least four separate locations; that the fence had degraded and was
failing to maintain the enclosure around the Quarantined Premises in at least
one area; that at least three gates had been opened;and that deer tracks were
visible in and around one of the open areas in the sand on both sides of the
fence, evidencing movement of deer into the Quarantined Premises.
The overall incidence of clinical CWD in white-tailed deer was 82%
Species (cohort) CWD (cases/total) Incidence (%) Age at CWD death
(mo)
*** Spraker suggested an interesting explanation for the occurrence of CWD.
The deer pens at the Foot Hills Campus were built some 30-40 years ago by a Dr.
Bob Davis. At or abut that time, allegedly, some scrapie work was conducted at
this site. When deer were introduced to the pens they occupied ground that had
previously been occupied by sheep.
the cwd tse prion aka mad cow type disease is not your normal pathogen.
The TSE prion disease survives ashing to 600 degrees celsius, that’s around
1112 degrees farenheit.
you cannot cook the TSE prion disease out of meat.
you can take the ash and mix it with saline and inject that ash into a
mouse, and the mouse will go down with TSE.
Prion Infected Meat-and-Bone Meal Is Still Infectious after Biodiesel
Production as well.
the TSE prion agent also survives Simulated Wastewater Treatment Processes.
IN fact, you should also know that the TSE Prion agent will survive in the
environment for years, if not decades.
you can bury it and it will not go away.
The TSE agent is capable of infected your water table i.e. Detection of
protease-resistant cervid prion protein in water from a CWD-endemic area.
it’s not your ordinary pathogen you can just cook it out and be done with.
that’s what’s so worrisome about Iatrogenic mode of transmission, a simple
autoclave will not kill this TSE prion agent.
New studies on the heat resistance of hamster-adapted scrapie agent:
Threshold survival after ashing at 600°C suggests an inorganic template of
replication
NOW, here is the most frightening aspect of all this, is the proven
secondhand transmission, i.e. pass if forward mode, via iatrogenic (medical,
surgical, dental, blood, tissue). you may never eat meat, but go to a hospital
near you, it’s a proven risk factor, our hospitals have been exposed. I have
countless articles on hospitals DEAR JOHN mad cow letters i.e. you have been
exposed via surgery).
Transmission of Creutzfeldt-Jakob disease to a chimpanzee by electrodes
contaminated during neurosurgery.
Gibbs CJ Jr, Asher DM, Kobrine A, Amyx HL, Sulima MP, Gajdusek DC.
Laboratory of Central Nervous System Studies, National Institute of
Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD
20892.
Stereotactic multicontact electrodes used to probe the cerebral cortex of a
middle aged woman with progressive dementia were previously implicated in the
accidental transmission of Creutzfeldt-Jakob disease (CJD) to two younger
patients. The diagnoses of CJD have been confirmed for all three cases. More
than two years after their last use in humans, after three cleanings and
repeated sterilisation in ethanol and formaldehyde vapour, the electrodes were
implanted in the cortex of a chimpanzee. Eighteen months later the animal became
ill with CJD. This finding serves to re-emphasise the potential danger posed by
reuse of instruments contaminated with the agents of spongiform
encephalopathies, even after scrupulous attempts to clean them.
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=8006664&dopt=Abstract
SOURCE REFERENCES
The infectious agents responsible for transmissible spongiform
encephalopathy (TSE) are notoriously resistant to most physical and chemical
methods used for inactivating pathogens, including heat. It has long been
recognized, for example, that boiling is ineffective and that higher
temperatures are most efficient when combined with steam under pressure (i.e.,
autoclaving). As a means of decontamination, dry heat is used only at the
extremely high temperatures achieved during incineration, usually in excess of
600°C. It has been assumed, without proof, that incineration totally inactivates
the agents of TSE, whether of human or animal origin.
Prion Infected Meat-and-Bone Meal Is Still Infectious after Biodiesel
Production
Histochemical analysis of hamster brains inoculated with the solid residue
showed typical spongiform degeneration and vacuolation. Re-inoculation of these
brains into a new cohort of hamsters led to onset of clinical scrapie symptoms
within 75 days, suggesting that the specific infectivity of the prion protein
was not changed during the biodiesel process. The biodiesel reaction cannot be
considered a viable prion decontamination method for MBM, although we observed
increased survival time of hamsters and reduced infectivity greater than 6 log
orders in the solid MBM residue. Furthermore, results from our study compare for
the first time prion detection by Western Blot versus an infectivity bioassay
for analysis of biodiesel reaction products. We could show that biochemical
analysis alone is insufficient for detection of prion infectivity after a
biodiesel process.
Detection of protease-resistant cervid prion protein in water from a
CWD-endemic area
The data presented here demonstrate that sPMCA can detect low levels of
PrPCWD in the environment, corroborate previous biological and experimental data
suggesting long term persistence of prions in the environment2,3 and imply that
PrPCWD accumulation over time may contribute to transmission of CWD in areas
where it has been endemic for decades. This work demonstrates the utility of
sPMCA to evaluate other environmental water sources for PrPCWD, including
smaller bodies of water such as vernal pools and wallows, where large numbers of
cervids congregate and into which prions from infected animals may be shed and
concentrated to infectious levels.
A Quantitative Assessment of the Amount of Prion Diverted to Category 1
Materials and Wastewater During Processing
Keywords:Abattoir;bovine spongiform encephalopathy;QRA;scrapie;TSE
In this article the development and parameterization of a quantitative
assessment is described that estimates the amount of TSE infectivity that is
present in a whole animal carcass (bovine spongiform encephalopathy [BSE] for
cattle and classical/atypical scrapie for sheep and lambs) and the amounts that
subsequently fall to the floor during processing at facilities that handle
specified risk material (SRM). BSE in cattle was found to contain the most oral
doses, with a mean of 9864 BO ID50s (310, 38840) in a whole carcass compared to
a mean of 1851 OO ID50s (600, 4070) and 614 OO ID50s (155, 1509) for a sheep
infected with classical and atypical scrapie, respectively. Lambs contained the
least infectivity with a mean of 251 OO ID50s (83, 548) for classical scrapie
and 1 OO ID50s (0.2, 2) for atypical scrapie. The highest amounts of infectivity
falling to the floor and entering the drains from slaughtering a whole carcass
at SRM facilities were found to be from cattle infected with BSE at rendering
and large incineration facilities with 7.4 BO ID50s (0.1, 29), intermediate
plants and small incinerators with a mean of 4.5 BO ID50s (0.1, 18), and
collection centers, 3.6 BO ID50s (0.1, 14). The lowest amounts entering drains
are from lambs infected with classical and atypical scrapie at intermediate
plants and atypical scrapie at collection centers with a mean of 3 × 10−7 OO
ID50s (2 × 10−8, 1 × 10−6) per carcass. The results of this model provide key
inputs for the model in the companion paper published here.
============================================================================
*** Infectious agent of sheep scrapie may persist in the environment for at
least 16 years ***
Gudmundur Georgsson1, Sigurdur Sigurdarson2 and Paul Brown3
Longitudinal Detection of Prion Shedding in Saliva and Urine by
CWD-Infected Deer by RT-QuIC
Davin M. Henderson1, Nathaniel D. Denkers1, Clare E. Hoover1, Nina
Garbino1, Candace K. Mathiason1 and Edward A. Hoover1# + Author
Affiliations
1Prion Research Center, Department of Microbiology, Immunology, and
Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado
State University, Fort Collins, CO 80523 ABSTRACT Chronic Wasting Disease (CWD)
is an emergent, rapidly spreading prion disease of cervids. Shedding of
infectious prions in saliva and urine is thought to be an important factor in
CWD transmission. To help elucidate this issue, we applied an in vitro
amplification assay to determine the onset, duration, and magnitude of prion
shedding in longitudinally collected saliva and urine samples from CWD-exposed
white-tailed deer. We detected prion shedding as early as 3 months after CWD
exposure and sustained shedding throughout the disease course. We estimated that
a 50% lethal dose (LD50) for cervidized transgenic mice would be contained in 1
ml of infected deer saliva or 10 ml or urine. Given the average course of
infection and daily production of these body fluids, an infected deer would shed
thousands of prion infectious dosesover the course of CWD infection. The direct
and indirect environmental impact of this magnitude of prion shedding for cervid
and non-cervid species is surely significant.
Importance: Chronic wasting disease (CWD) is an emerging and uniformly
fatal prion disease affecting free ranging deer and elk and now recognized in 22
United States and 2 C anadian Provinces. It is unique among prion diseases in
that it is transmitted naturally though wild populations. A major hypothesis for
CWD's florid spread is that prions are shed in excreta and transmitted via
direct or indirect environmental contact. Here we use a rapid in vitro assay to
show that infectious doses of CWD prions are in fact shed throughout the
multi-year disease course in deer. This finding is an important advance in
assessing the risks posed by shed CWD prions to animals as well as humans.
FOOTNOTES
↵#To whom correspondence should be addressed: Edward A. Hoover, Prion
Research Center, Department of Microbiology, Immunology and Pathology, Colorado
State University, Fort Collins, Colorado, US Email: edward.hoover@colostate.edu
98 | Veterinary Record | January 24, 2015
EDITORIAL
Scrapie: a particularly persistent pathogen
Cristina Acín
Resistant prions in the environment have been the sword of Damocles for
scrapie control and eradication. Attempts to establish which physical and
chemical agents could be applied to inactivate or moderate scrapie infectivity
were initiated in the 1960s and 1970s,with the first study of this type focusing
on the effect of heat treatment in reducing prion infectivity (Hunter and
Millson 1964). Nowadays, most of the chemical procedures that aim to inactivate
the prion protein are based on the method developed by Kimberlin and
collaborators (1983). This procedure consists of treatment with 20,000 parts per
million free chlorine solution, for a minimum of one hour, of all surfaces that
need to be sterilised (in laboratories, lambing pens, slaughterhouses, and so
on). Despite this, veterinarians and farmers may still ask a range of questions,
such as ‘Is there an official procedure published somewhere?’ and ‘Is there an
international organisation which recommends and defines the exact method of
scrapie decontamination that must be applied?’
From a European perspective, it is difficult to find a treatment that could
be applied, especially in relation to the disinfection of surfaces in lambing
pens of affected flocks. A 999/2001 EU regulation on controlling spongiform
encephalopathies (European Parliament and Council 2001) did not specify a
particular decontamination measure to be used when an outbreak of scrapie is
diagnosed. There is only a brief recommendation in Annex VII concerning the
control and eradication of transmissible spongiform encephalopathies (TSE
s).
Chapter B of the regulation explains the measures that must be applied if
new caprine animals are to be introduced to a holding where a scrapie outbreak
has previously been diagnosed. In that case, the statement indicates that
caprine animals can be introduced ‘provided that a cleaning and disinfection of
all animal housing on the premises has been carried out following
destocking’.
Issues around cleaning and disinfection are common in prion prevention
recommendations, but relevant authorities, veterinarians and farmers may have
difficulties in finding the specific protocol which applies. The European Food
and Safety Authority (EFSA ) published a detailed report about the efficacy of
certain biocides, such as sodium hydroxide, sodium hypochlorite, guanidine and
even a formulation of copper or iron metal ions in combination with hydrogen
peroxide, against prions (EFSA 2009). The report was based on scientific
evidence (Fichet and others 2004, Lemmer and others 2004, Gao and others 2006,
Solassol and others 2006) but unfortunately the decontamination measures were
not assessed under outbreak conditions.
The EFSA Panel on Biological Hazards recently published its conclusions on
the scrapie situation in the EU after 10 years of monitoring and control of the
disease in sheep and goats (EFSA 2014), and one of the most interesting findings
was the Icelandic experience regarding the effect of disinfection in scrapie
control. The Icelandic plan consisted of: culling scrapie-affected sheep or the
whole flock in newly diagnosed outbreaks; deep cleaning and disinfection of
stables, sheds, barns and equipment with high pressure washing followed by
cleaning with 500 parts per million of hypochlorite; drying and treatment with
300 ppm of iodophor; and restocking was not permitted for at least two years.
Even when all of these measures were implemented, scrapie recurred on several
farms, indicating that the infectious agent survived for years in the
environment, even as many as 16 years after restocking (Georgsson and others
2006).
In the rest of the countries considered in the EFSA (2014) report,
recommendations for disinfection measures were not specifically defined at the
government level. In the report, the only recommendation that is made for sheep
is repopulation with sheep with scrapie-resistant genotypes. This reduces the
risk of scrapie recurrence but it is difficult to know its effect on the
infection.
Until the EFSA was established (in May 2003), scientific opinions about TSE
s were provided by the Scientific Steering Committee (SSC) of the EC, whose
advice regarding inactivation procedures focused on treating animal waste at
high temperatures (150°C for three hours) and high pressure alkaline hydrolysis
(SSC 2003). At the same time, the TSE Risk Management Subgroup of the Advisory
Committee on Dangerous Pathogens (ACDP) in the UK published guidance on safe
working and the prevention of TSE infection. Annex C of the ACDP report
established that sodium hypochlorite was considered to be effective, but only if
20,000 ppm of available chlorine was present for at least one hour, which has
practical limitations such as the release of chlorine gas, corrosion,
incompatibility with formaldehyde, alcohols and acids, rapid inactivation of its
active chemicals and the stability of dilutions (ACDP 2009).
In an international context, the World Organisation for Animal Health (OIE)
does not recommend a specific disinfection protocol for prion agents in its
Terrestrial Code or Manual. Chapter 4.13 of the Terrestrial Code, General
recommendations on disinfection and disinsection (OIE 2014), focuses on
foot-and-mouth disease virus, mycobacteria and Bacillus anthracis, but not on
prion disinfection. Nevertheless, the last update published by the OIE on bovine
spongiform encephalopathy (OIE 2012) indicates that few effective
decontamination techniques are available to inactivate the agent on surfaces,
and recommends the removal of all organic material and the use of sodium
hydroxide, or a sodium hypochlorite solution containing 2 per cent available
chlorine, for more than one hour at 20ºC.
The World Health Organization outlines guidelines for the control of TSE s,
and also emphasises the importance of mechanically cleaning surfaces before
disinfection with sodium hydroxide or sodium hypochlorite for one hour (WHO
1999).
Finally, the relevant agencies in both Canada and the USA suggest that the
best treatments for surfaces potentially contaminated with prions are sodium
hydroxide or sodium hypochlorite at 20,000 ppm. This is a 2 per cent solution,
while most commercial household bleaches contain 5.25 per cent sodium
hypochlorite. It is therefore recommended to dilute one part 5.25 per cent
bleach with 1.5 parts water (CDC 2009, Canadian Food Inspection Agency
2013).
So what should we do about disinfection against prions? First, it is
suggested that a single protocol be created by international authorities to
homogenise inactivation procedures and enable their application in all
scrapie-affected countries. Sodium hypochlorite with 20,000 ppm of available
chlorine seems to be the procedure used in most countries, as noted in a paper
summarised on p 99 of this issue of Veterinary Record (Hawkins and others 2015).
But are we totally sure of its effectiveness as a preventive measure in a
scrapie outbreak? Would an in-depth study of the recurrence of scrapie disease
be needed?
What we can conclude is that, if we want to fight prion diseases, and
specifically classical scrapie, we must focus on the accuracy of diagnosis,
monitoring and surveillance; appropriate animal identification and control of
movements; and, in the end, have homogeneous and suitable protocols to
decontaminate and disinfect lambing barns, sheds and equipment available to
veterinarians and farmers. Finally, further investigations into the resistance
of prion proteins in the diversity of environmental surfaces are required.
References
snip...
98 | Veterinary Record | January 24, 2015
Persistence of ovine scrapie infectivity in a farm environment following
cleaning and decontamination
Steve A. C. Hawkins, MIBiol, Pathology Department1, Hugh A. Simmons, BVSc
MRCVS, MBA, MA Animal Services Unit1, Kevin C. Gough, BSc, PhD2 and Ben C.
Maddison, BSc, PhD3 + Author Affiliations
1Animal and Plant Health Agency, Woodham Lane, New Haw, Addlestone, Surrey
KT15 3NB, UK 2School of Veterinary Medicine and Science, The University of
Nottingham, Sutton Bonington, Loughborough, Leicestershire LE12 5RD, UK 3ADAS
UK, School of Veterinary Medicine and Science, The University of Nottingham,
Sutton Bonington, Loughborough, Leicestershire LE12 5RD, UK E-mail for
correspondence: ben.maddison@adas.co.uk Abstract Scrapie of sheep/goats and
chronic wasting disease of deer/elk are contagious prion diseases where
environmental reservoirs are directly implicated in the transmission of disease.
In this study, the effectiveness of recommended scrapie farm decontamination
regimens was evaluated by a sheep bioassay using buildings naturally
contaminated with scrapie. Pens within a farm building were treated with either
20,000 parts per million free chorine solution for one hour or were treated with
the same but were followed by painting and full re-galvanisation or replacement
of metalwork within the pen. Scrapie susceptible lambs of the PRNP genotype
VRQ/VRQ were reared within these pens and their scrapie status was monitored by
recto-anal mucosa-associated lymphoid tissue. All animals became infected over
an 18-month period, even in the pen that had been subject to the most stringent
decontamination process. These data suggest that recommended current guidelines
for the decontamination of farm buildings following outbreaks of scrapie do
little to reduce the titre of infectious scrapie material and that environmental
recontamination could also be an issue associated with these premises.
SNIP...
Discussion
Thorough pressure washing of a pen had no effect on the amount of
bioavailable scrapie infectivity (pen B). The routine removal of prions from
surfaces within a laboratory setting is treatment for a minimum of one hour with
20,000 ppm free chlorine, a method originally based on the use of brain
macerates from infected rodents to evaluate the effectiveness of decontamination
(Kimberlin and others 1983). Further studies have also investigated the
effectiveness of hypochlorite disinfection of metal surfaces to simulate the
decontamination of surgical devices within a hospital setting. Such treatments
with hypochlorite solution were able to reduce infectivity by 5.5 logs to lower
than the sensitivity of the bioassay used (Lemmer and others 2004). Analogous
treatment of the pen surfaces did not effectively remove the levels of scrapie
infectivity over that of the control pens, indicating that this method of
decontamination is not effective within a farm setting. This may be due to the
high level of biological matrix that is present upon surfaces within the farm
environment, which may reduce the amount of free chlorine available to
inactivate any infectious prion. Remarkably 1/5 sheep introduced into pen D had
also became scrapie positive within nine months, with all animals in this pen
being RAMALT positive by 18 months of age. Pen D was no further away from the
control pen (pen A) than any of the other pens within this barn. Localised hot
spots of infectivity may be present within scrapie-contaminated environments,
but it is unlikely that pen D area had an amount of scrapie contamination that
was significantly different than the other areas within this building.
Similarly, there were no differences in how the biosecurity of pen D was
maintained, or how this pen was ventilated compared with the other pens. This
observation, perhaps, indicates the slower kinetics of disease uptake within
this pen and is consistent with a more thorough prion removal and
recontamination. These observations may also account for the presence of
inadvertent scrapie cases within other studies, where despite stringent
biosecurity, control animals have become scrapie positive during challenge
studies using barns that also housed scrapie-affected animals (Ryder and others
2009). The bioassay data indicate that the exposure of the sheep to a farm
environment after decontamination efforts thought to be effective in removing
scrapie is sufficient for the animals to become infected with scrapie. The main
exposure routes within this scenario are likely to be via the oral route, during
feeding and drinking, and respiratory and conjunctival routes. It has been
demonstrated that scrapie infectivity can be efficiently transmitted via the
nasal route in sheep (Hamir and others 2008), as is the case for CWD in both
murine models and in white-tailed deer (Denkers and others 2010, 2013).
Recently, it has also been demonstrated that CWD prions presented as dust when
bound to the soil mineral montmorillonite can be infectious via the nasal route
(Nichols and others 2013). When considering pens C and D, the actual source of
the infectious agent in the pens is not known, it is possible that biologically
relevant levels of prion survive on surfaces during the decontamination regimen
(pen C). With the use of galvanising and painting (pen D) covering and sealing
the surface of the pen, it is possible that scrapie material recontaminated the
pens by the movement of infectious prions contained within dusts originating
from other parts of the barn that were not decontaminated or from other areas of
the farm.
Given that scrapie prions are widespread on the surfaces of affected farms
(Maddison and others 2010a), irrespective of the source of the infectious prions
in the pens, this study clearly highlights the difficulties that are faced with
the effective removal of environmentally associated scrapie infectivity. This is
likely to be paralleled in CWD which shows strong similarities to scrapie in
terms of both the dissemination of prions into the environment and the facile
mode of disease transmission. These data further contribute to the understanding
that prion diseases can be highly transmissible between susceptible individuals
not just by direct contact but through highly stable environmental reservoirs
that are refractory to decontamination.
The presence of these environmentally associated prions in farm buildings
make the control of these diseases a considerable challenge, especially in
animal species such as goats where there is lack of genetic resistance to
scrapie and, therefore, no scope to re-stock farms with animals that are
resistant to scrapie.
Scrapie Sheep Goats Transmissible spongiform encephalopathies (TSE)
Accepted October 12, 2014. Published Online First 31 October 2014
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.
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...
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
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 soon as possible for the following
reasons...
======
In the USA, under the Food and Drug Administrations 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.
======
31 Jan 2015 at 20:14 GMT
*** Ruminant feed ban for cervids in the United States? ***
Singeltary et al
31 Jan 2015 at 20:14 GMT
Article Citation: (2015)
AGE AND REPEATED BIOPSY INFLUENCE ANTEMORTEM PRPCWD TESTING IN MULE DEER
(ODOCOILEUS HEMIONUS) IN COLORADO, USA.
Journal of Wildlife Diseases In-Press. doi: http://dx.doi.org/10.7589/2014-12-284
Ahead of Print
AGE AND REPEATED BIOPSY INFLUENCE ANTEMORTEM PRPCWD TESTING IN MULE DEER
(ODOCOILEUS HEMIONUS) IN COLORADO, USA
Chris Geremia1,6,7 Jennifer A. Hoeting2, Lisa L. Wolfe3, Nathan L.
Galloway4, Michael F. Antolin4, Terry R. Spraker5, Michael W. Miller3, and N.
Thompson Hobbs1
1 Natural Resource Ecology Laboratory, Graduate Degree Program in Ecology,
Colorado State University, Fort Collins, Colorado, 80523-1499, USA
2 Department of Statistics, Colorado State University, Fort Collins,
Colorado 80523, USA
3 Colorado Division of Parks and Wildlife, Wildlife Health Program, 4330
Laporte Avenue, Fort Collins, Colorado 80521, USA
4 Department of Biology, Colorado State University, Fort Collins, Colorado
80523-1878, USA
5 Colorado State University Diagnostics Laboratory, Colorado State
University, Fort Collins, Colorado 80523, USA
Key words: Bayesian, capture–mark–recapture, chronic wasting disease, mule
deer, prion, test sensitivity
Abstract
Biopsy of rectal-mucosa associated lymphoid tissue provides a useful, but
imperfect, live-animal test for chronic wasting disease (CWD) in mule deer
(Odocoileus hemionus). It is difficult and expensive to complete these tests on
free-ranging animals, and wildlife health managers will benefit from methods
that can accommodate test results of varying quality. To this end, we developed
a hierarchical Bayesian model to estimate the probability that an individual is
infected based on test results. Our model was estimated with the use of data on
210 adult female mule deer repeatedly tested during 2010−2014. The ability to
identify infected individuals correctly declined with age and may have been
influenced by repeated biopsy. Fewer isolated lymphoid follicles (where PrPCWD
accumulates) were obtained in biopsies of older deer and the proportion of
follicles showing PrPCWD was reduced. A deer’s genotype in the prion gene (PRNP)
also influenced detection. At least five follicles were needed in a biopsy to
assure a 95% accurate test in PRNP genotype 225SS deer.
Received: December 15, 2014; Accepted: April 23, 2015
6 Current address: Yellowstone Center for Resources, P.O. Box 168,
Yellowstone National Park, Mammoth Hot Springs, Wyoming 82190, USA
7 Corresponding author (email: chris_geremia@nps.gov)
Friday, January 30, 2015
*** Scrapie: a particularly persistent pathogen ***
Wednesday, August 05, 2015
*** Ohio confirms to me Chronic Wasting Disease CWD Spreads 19 confirmed
cases to date ***
Just got off the phone with Christy Clevenger of Ohio
Ohio Department of Agriculture March 2012 – Present (3 years 6
months)Reynoldsburg, Ohio CWD program
Ms. Clevenger confirmed, to date, from the Yoder debacle, 1 confirmed case
of CWD from the Hunting Preserve, 2 confirmed cases from the Breeding Farm, and
16 confirmed cases of CWD from the Breeder Depopulation, with a total to date of
19 cases of CWD in Ohio...
Terry
Saturday, July 18, 2015
CHARLES "SAM" JAMES, Columbia, Missouri, was charged in a one-count federal
indictment for violations of the Lacey Act involved the sale of white-tailed
deer transported in violation of Missouri and Florida law
Tuesday, November 27, 2012
Pennsylvania ‘Pink 23’ Adams County exposed CWD Escaped Deer shot, but
where are the other escapees ?
Saturday, June 29, 2013
PENNSYLVANIA CAPTIVE CWD INDEX HERD MATE YELLOW *47 STILL RUNNING LOOSE IN
INDIANA, YELLOW NUMBER 2 STILL MISSING, AND OTHERS ON THE RUN STILL IN LOUISIANA
Louisiana Deer Quarantine
Tuesday, August 11, 2015
Wisconsin doing what it does best, procrastinating about CWD yet again
thanks to Governor Walker
GRASSHOPPER TO MASTER Obi-Wan Kenobi CWD TEXAS CAPTIVE
‘’I see no evidence whatsoever here for a genetic link. The numbers are
statistically insignificant and co-housing in contaminated facilities would
strongly predispose to this outcome.’’
‘’if the father did have a bad amino acid variant allele, it would be
diluted to heterozygozity with a normal gene in the half the four descendants
since the father never would have survived to breeding age with two bad copies.
sort of like met/val at position 129 in humans with greatly lengthened
incubation times if prnp is propagating at all. Mutations such as repeat
expansion leading to positive dominant infection have not been documented in
cervids.’’
On 09 08 15, at 9:09 AM, Terry S. Singeltary Sr.
wrote: ‘’
cwd Texas and then there were 4?
genetic link ?
He said 42 deer have been killed and tested since July 28, and three
additional positives were the result.
***He added that all four deer confirmed to have the disease were males
from the same father, which leads him to believe the problem is genetic.
snip...
*** HAVE YOU BEEN THUNDERSTRUCK ?
on my mothers grave, when I wrote up the ‘have you been thunderstruck’
about super ovulation, and what if? I had no clue about all this. hell, I had it
in draft for a month. then a week or so later, bam.
it’s been like this all along Obi-Wan Kenobi.
every shooting pen owner in Texas are praying this familial cwd is the
going thing now.
no link to sperm.
no link to super ovulation.
they sell those sperm straws like the meth heads and crack heads sell meth
and crack.
genetic link with four deer in the same herd, same father ?
familial ?
sperm ?
super ovulation ?
what say ye master ?
grasshopper
Friday, August 07, 2015
Texas CWD Captive, and then there were 4 ?
Thursday, August 06, 2015
WE HAVE LOST TEXAS TO CWD TASK FORCE CATERING TO INDUSTRY
Tuesday, July 21, 2015
Texas CWD Medina County Herd Investigation Update July 16, 2015
• 66 Texas sites, 2 Mexico sites
Monday, August 10, 2015
*** Scientific Opinion on a request for a review of a scientific
publication concerning the zoonotic potential of ovine scrapie prions
Thursday, July 24, 2014
*** Protocol for further laboratory investigations into the distribution of
infectivity of Atypical BSE SCIENTIFIC REPORT OF EFSA New protocol for Atypical
BSE investigations
Wednesday, July 15, 2015
*** Additional BSE TSE prion testing detects pathologic lesion in unusual
brain location and PrPsc by PMCA only, how many cases have we missed?
Wednesday, July 29, 2015
Further characterisation of transmissible spongiform encephalopathy
phenotypes after inoculation of cattle with two temporally separated sources of
sheep scrapie from Great Britain
Wednesday, July 29, 2015
Porcine Prion Protein Amyloid or mad pig disease PSE
Monday, August 10, 2015
Detection and Quantification of beta-Amyloid, Pyroglutamyl A beta, and Tau
in Aged Canines
http://caninespongiformencephalopathy.blogspot.com/2015/08/detection-and-quantification-of-beta.html
Friday, August 7, 2015
Transgenic Mouse Bioassay: Evidence That Rabbits Are Susceptible to a
Variety of Prion Isolates
Thursday, July 30, 2015
SCRAPIE USDA APHIS June 2015 Monthly Report
Tuesday, June 23, 2015
Report on the monitoring and testing of ruminants for the presence of
transmissible spongiform encephalopathies (TSEs) in the EU in 2013 Final version
18 May 2015
Saturday, March 21, 2015
*** Canada and United States Creutzfeldt Jakob TSE Prion Disease Incidence
Rates Increasing
*** HUMAN MAD COW DISEASE nvCJD TEXAS CASE NOT LINKED TO EUROPEAN TRAVEL
CDC ***
Sunday, November 23, 2014
*** Confirmed Variant Creutzfeldt-Jakob Disease (variant CJD) Case in Texas
in June 2014 confirmed as USA case NOT European ***
the patient had resided in Kuwait, Russia and Lebanon. The completed
investigation did not support the patient's having had extended travel to
European countries, including the United Kingdom, or travel to Saudi Arabia. The
specific overseas country where this patient’s infection occurred is less clear
largely because the investigation did not definitely link him to a country where
other known vCJD cases likely had been infected.
Sunday, December 14, 2014
*** ALERT new variant Creutzfeldt Jakob Disease nvCJD or vCJD, sporadic CJD
strains, TSE prion aka Mad Cow Disease United States of America Update December
14, 2014 Report ***
Thursday, July 30, 2015
Professor Lacey believes sporadic CJD itself originates from a cattle
infection number of cattle farmers falling victim to Creutzfeld-Jakob Disease is
much too high to be mere chance
Tuesday, August 4, 2015
*** FDA U.S. Measures to Protect Against BSE aka MAD COW DISEASE ***
Thursday, July 30, 2015
*** Prion Disease Induces Alzheimer Disease-Like Neuropathologic Changes
Self-Propagative Replication of Ab Oligomers Suggests Potential
Transmissibility in Alzheimer Disease
Received July 24, 2014; Accepted September 16, 2014; Published November 3,
2014
*** Singeltary comment ;
Terry S. Singeltary Sr.
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