MISSOURI CHRONIC WASTING DISEASE CWD TSE PRION UPDATE
Missouri Deer Season Summary & Population Status Report 2014-15
22 Missouri Department of Conservation
Chronic Wasting Disease
Chronic wasting disease (CWD) belongs to a group of diseases known as
transmissible spongiform encephalopathies (TSEs) which cause deterioration of
the brain in cervids such as deer, elk, and moose. CWD is always fatal, but can
take months or years before symptoms appear. These symptoms can include changes
in behavior, extreme weight loss, excessive salivation, stumbling, and tremors.
Infected cervids can spread CWD by contacting other cervids and via excrements
(e.g., feces, urine, and saliva) in the environment. Additionally, CWD can
spread geographically through the natural movements of infected cervids and the
human-assisted movement of infected carcasses (e.g., hunter-harvested deer) or
captive cervids. To determine if a cervid is CWD-positive, a laboratory test of
the brain stem or lymph node tissue is required.
Current research indicates that CWD cannot spread to domestic livestock,
such as sheep or cattle. The Center for Disease Control and Prevention (CDC) has
found no evidence that CWD can infect people. While there is no scientific
evidence that CWD is transmissible to humans or animals other than deer and
cervids, public health officials do not recommend the consumption of the parts
(i.e., brain, spinal cord, eyes, spleen, and lymph nodes) where prions are known
to accumulate.
CWD in Missouri: Spring 2015 Update
CWD was first detected in Missouri in 2010 at a captive big-game hunting
preserve in Linn County. In January 2012, the first free-ranging CWD-positive
deer were detected in Macon County. MDC implemented several management actions
within a six-county CWD “Containment Zone” to limit the spread and prevalence of
the disease, including: 1) The removal of the antler point restriction (APR)
because it promoted an older age structure of bucks, which often have higher
infection rates. The APR also protected yearling males, which disperse from
their birth area for new territory, which is a significant means of spreading
CWD across the landscape. 2) The placement of feed, minerals, and other
consumable deer attractants was banned, as these materials artificially
concentrate deer, thus increasing the likelihood of disease transmission. 3) In
addition to statewide routine sampling that began in 2002, MDC increased efforts
to sample hunter-harvested deer in the Containment Zone and implemented targeted
culling in the Core Areas (see red outlined areas in the map above) to decrease
the spread and prevalence. Additionally, post-season targeted efforts have
proven more effective at removing CWD-positive deer from the landscape than
regular hunter-harvest, with 65% of the CWD-positive deer detected in Missouri
to date being removed after the close of annual deer seasons.
In December of 2014 a CWD-positive deer was detected in Adair County,
representing the first CWD detection outside the original CWD Core Area.
Additionally, in March of 2015, a hunter-harvested deer from the 2014-15 deer
season tested positive for CWD in Cole County marking the first time CWD was
detected outside of the Containment Zone. As of June 2015, CWD has been detected
in 26 free-ranging deer in Macon (19), Adair (6), and Cole (1) counties, and 11
captive deer in Linn (1) and Macon (10) counties. In response, the CWD
Management Zones have been expanded (refer to shaded counties in the map above)
and during the 2015-16 deer season will have increased CWD testing of
hunter-harvested deer, removal of the antler point restriction, and allowance of
two firearm antlerless permits per hunter within each county. Additional
management actions will be considered for the 2016-17 deer season.
snip...
Modeling Chronic Wasting Disease Dynamics and Impacts on White-tailed Deer
in Missouri
In collaboration with the University of Missouri, MDC has implemented a
research project to model chronic wasting disease (CWD) distribution and
potential impacts on Missouri’s deer population. We plan to model the
distribution and prevalence of CWD currently and in the future given various
scenarios. This will allow us to model potential impacts of CWD on the deer
herd, including survival and abundance. Additionally this information may
provide insight on management adjustments that could limit CWD distribution and
prevalence.
In addition to the application to the CWD Management Zones it will allow
MDC to evaluate the impact of various management practices on CWD prevalence and
distribution. Also, the study will provide the ability to compare various
monitoring strategies, thus increase our ability to detect CWD early so that
management efforts can be effective, while ensuring the efficient use of
resources.
Refer to page 22 for more information on CWD.
For more information, contact the Wildlife Health Program at (573)
815-7900.
Figure 16. This map illustrates the distribution of detected CWD-positive
deer, CWD Management Zones, and Core Areas as of June 2015.
>>> Current research indicates that CWD cannot spread to domestic
livestock, such as sheep or cattle. The Center for Disease Control and
Prevention (CDC) has found no evidence that CWD can infect people.
<<<
***NOT SO FAST HERE. there is research showing that the above statements
are not absolute, and in fact, wrong. just wishful thinking. please see science
;
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.***
================
PRION2013 CONGRESSIONAL ABSTRACTS CWD
Sunday, August 25, 2013
HD.13: CWD infection in the spleen of humanized transgenic mice
Liuting Qing and Qingzhong Kong
Case Western Reserve University; Cleveland, OH USA
Chronic wasting disease (CWD) is a widespread prion disease in free-ranging
and captive cervid species in North America, and there is evidence suggesting
the existence of multiple CWD strains. The susceptibility of human CNS and
peripheral organs to the various CWD prion strains remains largely unclear.
Current literature suggests that the classical CWD strain is unlikely to infect
human brain, but the potential for peripheral infection by CWD in humans is
unknown. We detected protease-resistant PrpSc in the spleens of a few humanized
transgenic mice that were intracerebrally inoculated with natural CWD isolates,
but PrpSc was not detected in the brains of any of the CWD-inoculated mice.
***Our ongoing bioassays in humanized Tg mice indicate that intracerebral
challenge with such PrpSc-positive humanized mouse spleen already led to prion
disease in most animals. ***These results indicate that the CWD prion may have
the potential to infect human peripheral lymphoid tissues.
Oral.15: Molecular barriers to zoonotic prion transmission: Comparison of
the ability of sheep, cattle and deer prion disease isolates to convert normal
human prion protein to its pathological isoform in a cell-free system
Marcelo A.Barria,1 Aru Balachandran,2 Masanori Morita,3 Tetsuyuki
Kitamoto,4 Rona Barron,5 Jean Manson,5 Richard Kniqht,1 James W. lronside1 and
Mark W. Head1
1National CJD Research and Surveillance Unit; Centre for Clinical Brain
Sciences; School of Clinical Sciences; The University of Edinburgh; Edinburgh,
UK; 2National and OIE Reference Laboratory for Scrapie and CWD; Canadian Food
Inspection Agency; Ottawa Laboratory; Fallowfield. ON Canada; 3Infectious
Pathogen Research Section; Central Research Laboratory; Japan Blood Products
Organization; Kobe, Japan; 4Department of Neurological Science; Tohoku
University Graduate School of Medicine; Sendai. Japan; 5Neurobiology Division;
The Roslin Institute and R(D)SVS; University of Edinburgh; Easter Bush;
Midlothian; Edinburgh, UK
Background. Bovine spongiform encephalopathy (BSE) is a known zoonotic
prion disease, resulting in variant Creurzfeldt- Jakob disease (vCJD) in humans.
In contrast, classical scrapie in sheep is thought to offer little or no danger
to human health. However, a widening range of prion diseases have been
recognized in cattle, sheep and deer. The risks posed by individual animal prion
diseases to human health cannot be determined a priori and are difficult to
assess empirically. The fundamemal event in prion disease pathogenesis is
thought to be the seeded conversion of normal prion protein (PrPC) to its
pathological isoform (PrPSc). Here we report the use of a rapid molecular
conversion assay to test whether brain specimens from different animal prion
diseases are capable of seeding the conversion of human PrPC ro PrPSc.
Material and Methods. Classical BSE (C-type BSE), H-type BSE, L-type BSE,
classical scrapie, atypical scrapie, chronic wasting disease and vCJD brain
homogenates were tested for their ability to seed conversion of human PrPC to
PrPSc in protein misfolding cyclic amplification (PMCA) reactions. Newly formed
human PrPSc was detected by protease digestion and western blotting using the
antibody 3F4.
Results. C-type BSE and vCJD were found to efficiently convert PrPC to
PrPSc. Scrapie failed to convert human PrPC to PrPSc. Of the other animal prion
diseases tested only chronic wasting disease appeared to have the capability ro
convert human PrPC to PrPSc. The results were consistent whether the human PrPC
came from human brain, humanised transgenic mouse brain or from cultured human
cells and the effect was more pronounced for PrPC with methionine at codon 129
compared with that with valine.
Conclusion. Our results show that none of the tested animal prion disease
isolates are as efficient as C-type BSE and vCJD in converting human prion
protein in this in vitro assay. ***However, they also show that there is no
absolute barrier ro conversion of human prion protein in the case of chronic
wasting disease.
PRION2013 CONGRESSIONAL ABSTRACTS CWD
Sunday, August 25, 2013
***Chronic Wasting Disease CWD risk factors, humans, domestic cats, blood,
and mother to offspring transmission
cwd to humans ???
there has been no official documentation of cwd to humans on paper, to
date.
cwd transmission studies on humans are illegal.
cwd transmits freely to the squirrel monkey, but not yet to the macaque,
and the macaque is a bit closer to humans than the squirrel monkey.
still, with cwd freely transmitting to the squirrel monkey, scientist are
very concerned about the cwd to human risk factor, exposure, and potential
iatrogenic transmission there from.
85% of human TSE is sporadic cjd, and each and every one of them are up for
debate as to route and source. I believe that friendly fire (iatrogenic) or the
pass it forward mode of the TSE prion will be a large portion of that. all
iatrogenic cjd is, is sporadic cjd until the iatrogenic event is discovered,
documented, put into the academic and then the public domain, which very seldom
happens due to lack of trace back efforts.
see what the authors said about this casual link with cwd to human with the
case of Jeffrey Schwan 26 year old, and personal communications years ago with
cdc about that case. 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: Terry S. Singeltary Sr.
Sent: Saturday, November 15, 2014 9:29 PM
To: Terry S. Singeltary Sr.
Subject: THE EPIDEMIOLOGY OF CREUTZFELDT-JAKOB DISEASE R. G. WILL 1984
THE EPIDEMIOLOGY OF CREUTZFELDT-JAKOB DISEASE
R. G. WILL
1984
*** 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). (SEE LINK IN REPORT HERE...TSS) PLUS, THE CDC DID NOT PUT
THIS WARNING OUT FOR THE WELL BEING OF THE DEER AND ELK ;
snip...
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 ***
July's Milwaukee Journal Sentinel article did prod state officials to ask
CDC to investigate the cases of the three men who shared wild game feasts. The
two men the CDC is still investigating were 55 and 66 years old. But there's
also Kevin Boss, a Minnesota hunter who ate Barron County venison and died of
CJD at 41. And there's Jeff Schwan, whose Michigan Tech fraternity brothers used
to bring venison sausage back to the frat house. His mother, Terry, says that in
May 2001, Jeff, 26, began complaining about his vision. A friend noticed
misspellings in his e-mail, which was totally unlike him. Jeff began losing
weight. He became irritable and withdrawn. By the end of June, he couldn't
remember the four-digit code to open the garage door or when and how to feed his
parents' cats. At a family gathering in July, he stuck to his parents and
girlfriend, barely talking. "On the night we took him to the hospital, he was
speaking like he was drunk or high and I noticed his pupils were so dilated I
couldn't see the irises," his mother says. By then, Jeff was no longer able to
do even simple things on his computer at work, and "in the hospital, he couldn't
drink enough water." When he died on September 27, 2001, an autopsy confirmed he
had sporadic CJD.
In 2000, Belay looked into three CJD cases reported by The Denver Post, two
hunters who ate meat from animals killed in Wyoming and the daughter of a hunter
who ate venison from a plant that processed Colorado elk. All three died of CJD
before they were 30 years old. The CDC asked the USDA to kill 1,000 deer and elk
in the area where the men hunted. Belay and others reported their findings in
the Archives of Neurology, writing that although "circumstances suggested a link
between the three cases and chronic wasting disease, they could find no 'causal'
link." Which means, says Belay, "not a single one of those 1,000 deer tested
positive for CWD. For all we know, these cases may be CWD. What we have now
doesn't indicate a connection. That's reassuring, but it would be wrong to say
it will never happen."
So far, says NIH researcher Race, the two Wisconsin cases pinpointed by the
newspaper look like spontaneous CJD. "But we don't know how CWD would look in
human brains. It probably would look like some garden-variety sporadic CJD."
What the CDC will do with these cases and four others (three from Colorado and
Schwan from Upper Michigan), Race says, is "sequence the prion protein from
these people, inject it into mice and wait to see what the disease looks like in
their brains. That will take two years."
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.
*** 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. ***
*** IF CWD is not a risk factor for humans, then I guess the FDA et al
recalled all this CWD tainted elk tenderloin (2009 Exotic Meats USA of San
Antonio, TX) for the welfare and safety of the dead elk. ...tss
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.
Exotic Meats USA purchased 1 case of Elk Tenderloins weighing 16.9 lbs. The
Elk Tenderloin was sold from January 16 – 27, 2009. The Elk Tenderloins was
packaged in individual vacuum packs weighing approximately 3 pounds each. A
total of six packs of the Elk Tenderloins were sold to the public at the Exotic
Meats USA retail store. Consumers who still have the Elk Tenderloins should
return the product to Exotic Meats USA at 1003 NE Loop 410, San Antonio, TX
78209. Customers with concerns or questions about the Voluntary Elk Recall can
call 1-800-680-4375. The safety of our customer has always been and always will
be our number one priority.
Exotic Meats USA requests that for those customers who have products with
the production dates in question, do not consume or sell them and return them to
the point of purchase. Customers should return the product to the vendor. The
vendor should return it to the distributor and the distributor should work with
the state to decide upon how best to dispose. If the consumer is disposing of
the product he/she should consult with the local state EPA office.
#
RSS Feed for FDA Recalls Information11 [what's this?12]
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.
P.97: Scrapie transmits to white-tailed deer by the oral route and has a
molecular profile similar to chronic wasting disease and distinct from the
scrapie inoculum
Justin Greenlee1, S Jo Moore1, Jodi Smith1, M Heather West Greenlee2, and
Robert Kunkle1 1National Animal Disease Center; Ames, IA USA; 2Iowa State
University; Ames, IA USA
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 D 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 2
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, 2
distinct molecular profiles of PrPSc are present in the tissues of affected
deer, and inoculum of either profile readily passes to deer.
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.
Scrapie in Deer: Comparisons and Contrasts to Chronic Wasting Disease (CWD)
Justin J. Greenlee of the Virus and Prion Diseases Research Unit, National
Animal Disease Center, ARS, USDA, Ames, IA
snip... This highlights the facts that 1) prior to the onset of clinical
signs PrPSc is widely distributed in the CNS and lymphoid tissues and
2) currently used diagnostic methods are sufficient to detect PrPSc prior
to the onset of clinical signs. The results of this study suggest that there are
many similarities in the manifestation of CWD and scrapie in white-tailed deer
after IC inoculation including early and widespread presence of PrPSc in
lymphoid tissues, clinical signs of depression and weight loss progressing to
wasting, and an incubation time of 21-23 months. Moreover, western blots (WB)
done on brain material from the obex region have a molecular profile consistent
with CWD and distinct from tissues of the cerebrum or the scrapie inoculum.
However, results of microscopic and IHC examination indicate that there are
differences between the lesions expected in CWD and those that occur in deer
with scrapie: amyloid plaques were not noted in any sections of brain examined
from these deer and the pattern of immunoreactivity by IHC was diffuse rather
than plaque-like. After a natural route of exposure, 100% of white-tailed deer
were susceptible to scrapie. Deer developed clinical signs of wasting and mental
depression and were necropsied from 28 to 33 months PI. Tissues from these deer
were positive for scrapie by IHC and WB. Tissues with PrPSc immunoreactivity
included brain, tonsil, retropharyngeal and mesenteric lymph nodes, hemal node,
Peyer’s patches, and spleen. While two WB patterns have been detected in brain
regions of deer inoculated by the natural route, unlike the IC inoculated deer,
the pattern similar to the scrapie inoculum predominates.
2011 Annual Report Research Project: TRANSMISSION, DIFFERENTIATION, AND
PATHOBIOLOGY OF TRANSMISSIBLE SPONGIFORM ENCEPHALOPATHIES Location: Virus and
Prion Research Unit
2011 Annual Report In Objective 1, Assess cross-species transmissibility of
transmissible spongiform encephalopathies (TSEs) in livestock and wildlife,
numerous experiments assessing the susceptibility of various TSEs in different
host species were conducted. Most notable is deer inoculated with scrapie, which
exhibits similarities to chronic wasting disease (CWD) in deer suggestive of
sheep scrapie as an origin of CWD.
snip...
4. Accomplishments 1. Deer inoculated with domestic isolates of sheep
scrapie. Scrapie-affected deer exhibit 2 different patterns of disease
associated prion protein. In some regions of the brain the pattern is much like
that observed for scrapie, while in others it is more like chronic wasting
disease (CWD), the transmissible spongiform encephalopathy typically associated
with deer.
his work conducted by ARS scientists at the National Animal Disease Center,
Ames, IA suggests that an interspecies transmission of sheep scrapie to deer may
have been the origin of CWD. This is important for husbandry practices with both
captive deer, elk and sheep for farmers and ranchers attempting to keep their
herds and flocks free of CWD and scrapie.
White-tailed Deer are Susceptible to Scrapie by Natural Route of Infection
Jodi D. Smith, Justin J. Greenlee, and Robert A. Kunkle; Virus and Prion
Research Unit, National Animal Disease Center, USDA-ARS
snip... This work demonstrates for the first time that white-tailed deer
are susceptible to sheep scrapie by potential natural routes of inoculation.
In-depth analysis of tissues will be done to determine similarities between
scrapie in deer after intracranial and oral/intranasal inoculation and chronic
wasting disease resulting from similar routes of inoculation.
see full text ;
Transmission of chronic wasting disease of mule deer to Suffolk sheep
following intracerebral inoculation
Amir N. Hamir,1 Robert A. Kunkle, Randall C. Cutlip, Janice M. Miller,
Elizabeth S. Williams, Juergen A. Richt
Abstract. To determine the transmissibility of chronic wasting disease
(CWD) to sheep, 8 Suffolk lambs of various prion protein genotypes (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 (CWDmd). Two other
lambs were kept as noninoculated controls. Within 36 months postinoculation
(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 determined to be positive for
the abnormal prion protein (PrPres) 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 did not have clinical signs of disease at the termination of the study (72
MPI) and were euthanized. Of the 3 remaining inoculated sheep, 1 was found to
have SE, and its tissues were positive for PrPres. The sheep with clinical prion
disease (euthanized at 35 MPI) was of the heterozygous genotype (ARQ/VRQ), and
the sheep with subclinical disease (euthanized at 72 MPH) was of the homozygous
ARQ/ARQ genotype. These findings demonstrate that transmission of the CWDmd
agent to sheep via the intracerebral route is possible. Interestingly, the host
genotype may play a notable part in successful transmission and incubation
period of CWDmd.
snip.
This study involved intracerebral inoculation of CWDmd agent to sheep. This
is an unnatural route and is only an oblique reflection of the potential for
sheep to become infected under natural conditions of exposure. Based on the low
attack rate of the current intracerebral inoculation (IC) study, it is likely
that transmission of CWD to sheep by a more natural route, such as per os would
likely require a much larger dose of inoculum and may be much more difficult to
accomplish within the normal life span of the animal. On the other hand,
experimental studies of CWD from other cervid species (elk and whitetailed deer)
have not been documented in livestock.
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.
At this time a final assessment of relative risk for CWD transmission to
sheep is not possible. However, results of this study show that the diagnostic
confirmatory tests used for scrapie surveillance in the United States would also
allow detection of CWD in sheep, should it occur in this country.
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. However, the only sheep to develop clinical TSE within 35 MPI was
genotypically AV at PRNP codon 136, suggesting that host genotype may play a
notable part in successful transmission of the disease in this species. Although
in Suffolk sheep the AV variant at codon 136 is very rare,17 selective breeding
of Suffolk sheep with this codon has begun in the hope of testing this
differential susceptibility hypothesis in a future study of CWDmd transmission
to sheep.
PRION CONFERENCE 2014 HELD IN ITALY RECENTLY CWD BSE TSE UPDATE
> First transmission of CWD to transgenic mice over-expressing bovine
prion protein gene (TgSB3985)
PRION 2014 - PRIONS: EPIGENETICS and NEURODEGENERATIVE DISEASES – Shaping
up the future of prion research
Animal TSE Workshop 10.40 – 11.05 Talk Dr. L. Cervenakova First
transmission of CWD to transgenic mice over-expressing bovine prion protein gene
(TgSB3985)
Friday, August 14, 2015
Susceptibility of cattle to the agent of chronic wasting disease from elk
after intracranial inoculation
***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.
================
***Our study demonstrates susceptibility of adult cattle to oral
transmission of classical BSE. ***
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.
===============
***however in 1 C-type challenged animal, Prion 2015 Poster Abstracts S67
PrPsc was not detected using rapid tests for BSE.
***Subsequent testing resulted in the detection of pathologic lesion in
unusual brain location and PrPsc detection by PMCA only.
IBNC Tauopathy or TSE Prion disease, it appears, no one is sure
Singeltary Posted by flounder on 03 Jul 2015 at 16:53 GMT
Sunday, September 27, 2015
*** TEXAS CONFIRMATION OF BOVINE SPONGIFORM ENCEPHALOPATHY BSE TSE PRION IN
ONE SAMPLE OF SORGHUM DDGS OUT OF 168 DG SAMPLES ***
very disturbing...terry
Saturday, January 31, 2015
*** European red deer (Cervus elaphus elaphus) are susceptible to Bovine
Spongiform Encephalopathy BSE by Oral Alimentary route ***
P35
ADAPTATION OF CHRONIC WASTING DISEASE (CWD) INTO HAMSTERS, EVIDENCE OF A
WISCONSIN STRAIN OF CWD
Chad Johnson1, Judd Aiken2,3,4 and Debbie McKenzie4,5 1 Department of
Comparative Biosciences, University of Wisconsin, Madison WI, USA 53706 2
Department of Agriculture, Food and Nutritional Sciences, 3 Alberta Veterinary
Research Institute, 4.Center for Prions and Protein Folding Diseases, 5
Department of Biological Sciences, University of Alberta, Edmonton AB, Canada
T6G 2P5
The identification and characterization of prion strains is increasingly
important for the diagnosis and biological definition of these infectious
pathogens. Although well-established in scrapie and, more recently, in BSE,
comparatively little is known about the possibility of prion strains in chronic
wasting disease (CWD), a disease affecting free ranging and captive cervids,
primarily in North America. We have identified prion protein variants in the
white-tailed deer population and demonstrated that Prnp genotype affects the
susceptibility/disease progression of white-tailed deer to CWD agent. The
existence of cervid prion protein variants raises the likelihood of distinct CWD
strains. Small rodent models are a useful means of identifying prion strains. We
intracerebrally inoculated hamsters with brain homogenates and phosphotungstate
concentrated preparations from CWD positive hunter-harvested (Wisconsin CWD
endemic area) and experimentally infected deer of known Prnp genotypes. These
transmission studies resulted in clinical presentation in primary passage of
concentrated CWD prions. Subclinical infection was established with the other
primary passages based on the detection of PrPCWD in the brains of hamsters and
the successful disease transmission upon second passage. Second and third
passage data, when compared to transmission studies using different CWD inocula
(Raymond et al., 2007) indicate that the CWD agent present in the Wisconsin
white-tailed deer population is different than the strain(s) present in elk,
mule-deer and white-tailed deer from the western United States endemic
region.
PPo3-7:
Prion Transmission from Cervids to Humans is Strain-dependent
Qingzhong Kong, Shenghai Huang,*Fusong Chen, Michael Payne, Pierluigi
Gambetti and Liuting Qing Department of Pathology; Case western Reserve
University; Cleveland, OH USA *Current address: Nursing Informatics; Memorial
Sloan-Kettering Cancer Center; New York, NY USA
Key words: CWD, strain, human transmission
Chronic wasting disease (CWD) is a widespread prion disease in cervids
(deer and elk) in North America where significant human exposure to CWD is
likely and zoonotic transmission of CWD is a concern. Current evidence indicates
a strong barrier for transmission of the classical CWD strain to humans with the
PrP-129MM genotype. A few recent reports suggest the presence of two or more CWD
strains. What remain unknown is whether individuals with the PrP-129VV/MV
genotypes are also resistant to the classical CWD strain and whether humans are
resistant to all natural or adapted cervid prion strains. Here we report that a
human prion strain that had adopted the cervid prion protein (PrP) sequence
through passage in cervidized transgenic mice efficiently infected transgenic
mice expressing human PrP, indicating that the species barrier from cervid to
humans is prion strain-dependent and humans can be vulnerable to novel cervid
prion strains. Preliminary results on CWD transmission in transgenic mice
expressing human PrP-129V will also be discussed.
Acknowledgement Supported by NINDS NS052319 and NIA AG14359.
PPo2-27:
Generation of a Novel form of Human PrPSc by Inter-species Transmission of
Cervid Prions
Marcelo A. Barria,1 Glenn C. Telling,2 Pierluigi Gambetti,3 James A.
Mastrianni4 and Claudio Soto1 1Mitchell Center for Alzheimer's disease and
related Brain disorders; Dept of Neurology; University of Texas Houston Medical
School; Houston, TX USA; 2Dept of Microbiology, Immunology & Molecular
Genetics and Neurology; Sanders Brown Center on Aging; University of Kentucky
Medical Center; Lexington, KY USA; 3Institute of Pathology; Case western Reserve
University; Cleveland, OH USA; 4Dept of Neurology; University of Chicago;
Chicago, IL USA
Prion diseases are infectious neurodegenerative disorders affecting humans
and animals that result from the conversion of normal prion protein (PrPC) into
the misfolded and infectious prion (PrPSc). Chronic wasting disease (CWD) of
cervids is a prion disorder of increasing prevalence within the United States
that affects a large population of wild and captive deer and elk. CWD is highly
contagious and its origin, mechanism of transmission and exact prevalence are
currently unclear. The risk of transmission of CWD to humans is unknown.
Defining that risk is of utmost importance, considering that people have been
infected by animal prions, resulting in new fatal diseases. To study the
possibility that human PrPC can be converted into the infectious form by CWD
PrPSc we performed experiments using the Protein Misfolding Cyclic Amplification
(PMCA) technique, which mimic in vitro the process of prion replication. Our
results show that cervid PrPSc can induce the pathological conversion of human
PrPC, but only after the CWD prion strain has been stabilized by successive
passages in vitro or in vivo. Interestingly, this newly generated human PrPSc
exhibits a distinct biochemical pattern that differs from any of the currently
known forms of human PrPSc, indicating that it corresponds to a novel human
prion strain. Our findings suggest that CWD prions have the capability to infect
humans, and that this ability depends on CWD strain adaptation, implying that
the risk for human health progressively increases with the spread of CWD among
cervids.
PPo2-7:
Biochemical and Biophysical Characterization of Different CWD
Isolates
Martin L. Daus and Michael Beekes Robert Koch Institute; Berlin,
Germany
Key words: CWD, strains, FT-IR, AFM
Chronic wasting disease (CWD) is one of three naturally occurring forms of
prion disease. The other two are Creutzfeldt-Jakob disease in humans and scrapie
in sheep. CWD is contagious and affects captive as well as free ranging cervids.
As long as there is no definite answer of whether CWD can breach the species
barrier to humans precautionary measures especially for the protection of
consumers need to be considered. In principle, different strains of CWD may be
associated with different risks of transmission to humans. Sophisticated strain
differentiation as accomplished for other prion diseases has not yet been
established for CWD. However, several different findings indicate that there
exists more than one strain of CWD agent in cervids. We have analysed a set of
CWD isolates from white-tailed deer and could detect at least two biochemically
different forms of disease-associated prion protein PrPTSE. Limited proteolysis
with different concentrations of proteinase K and/or after exposure of PrPTSE to
different pH-values or concentrations of Guanidinium hydrochloride resulted in
distinct isolate-specific digestion patterns. Our CWD isolates were also
examined in protein misfolding cyclic amplification studies. This showed
different conversion activities for those isolates that had displayed
significantly different sensitivities to limited proteolysis by PK in the
biochemical experiments described above. We further applied Fourier transform
infrared spectroscopy in combination with atomic force microscopy. This
confirmed structural differences in the PrPTSE of at least two disinct CWD
isolates. The data presented here substantiate and expand previous reports on
the existence of different CWD strains.
UPDATED DATA ON 2ND CWD STRAIN
Wednesday, September 08, 2010
CWD PRION CONGRESS SEPTEMBER 8-11 2010
the tse prion aka mad cow type disease is not your normal pathogen.
The TSE prion disease survives ashing to 600 degrees celsius, that’s around
1112 degrees farenheit.
you cannot cook the TSE prion disease out of meat. you can take the ash and
mix it with saline and inject that ash into a mouse, and the mouse will go down
with TSE.
Prion Infected Meat-and-Bone Meal Is Still Infectious after Biodiesel
Production as well.
the TSE prion agent also survives Simulated Wastewater Treatment Processes.
IN fact, you should also know that the TSE Prion agent will survive in the
environment for years, if not decades.
you can bury it and it will not go away.
The TSE agent is capable of infected your water table i.e. Detection of
protease-resistant cervid prion protein in water from a CWD-endemic area.
it’s not your ordinary pathogen you can just cook it out and be done with.
that’s what’s so worrisome about Iatrogenic mode of transmission, a simple
autoclave will not kill this TSE prion agent.
Friday, January 30, 2015
*** Scrapie: a particularly persistent pathogen ***
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...
Saturday, January 31, 2015
European red deer (Cervus elaphus elaphus) are susceptible to Bovine
Spongiform Encephalopathy BSE by Oral Alimentary route
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? ***
31 Jan 2015 at 20:14 GMT
Sunday, September 27, 2015
*** TEXAS CONFIRMATION OF BOVINE SPONGIFORM ENCEPHALOPATHY BSE TSE PRION IN
ONE SAMPLE OF SORGHUM DDGS OUT OF 168 DG SAMPLES ***
very disturbing...terry
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.***
================
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
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.
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)
CWD, spreading it around...
for the game farm industry, and their constituents, to continue to believe
that they are _NOT_, and or insinuate that they have _NEVER_ been part of the
problem, will only continue to help spread cwd. the game farming industry, from
the shooting pens, to the urine mills, the antler mills, the sperm mills, velvet
mills, shooting pens, to large ranches, are not the only problem, but it is
painfully obvious that they have been part of the problem for decades and
decades, just spreading it around, as with transportation and or exportation and
or importation of cervids from game farming industry, and have been proven to
spread cwd. no one need to look any further than South Korea blunder ;
===========================================
spreading cwd around...
Between 1996 and 2002, chronic wasting disease was diagnosed in 39 herds of
farmed elk in Saskatchewan in a single epidemic. All of these herds were
depopulated as part of the Canadian Food Inspection Agency’s (CFIA) disease
eradication program. Animals, primarily over 12 mo of age, were tested for the
presence CWD prions following euthanasia. Twenty-one of the herds were linked
through movements of live animals with latent CWD from a single infected source
herd in Saskatchewan, 17 through movements of animals from 7 of the secondarily
infected herds.
***The source herd is believed to have become infected via importation of
animals from a game farm in South Dakota where CWD was subsequently diagnosed
(7,4). A wide range in herd prevalence of CWD at the time of herd depopulation
of these herds was observed. Within-herd transmission was observed on some
farms, while the disease remained confined to the introduced animals on other
farms.
spreading cwd around...
Friday, May 13, 2011
Chronic Wasting Disease (CWD) outbreaks and surveillance program in the
Republic of Korea
Hyun-Joo Sohn, Yoon-Hee Lee, Min-jeong Kim, Eun-Im Yun, Hyo-Jin Kim,
Won-Yong Lee, Dong-Seob Tark, In- Soo Cho, Foreign Animal Disease Research
Division, National Veterinary Research and Quarantine Service, Republic of Korea
Chronic wasting disease (CWD) has been recognized as an important prion
disease in native North America deer and Rocky mountain elks. The disease is a
unique member of the transmissible spongiform encephalopathies (TSEs), which
naturally affects only a few species. CWD had been limited to USA and Canada
until 2000.
On 28 December 2000, information from the Canadian government showed that a
total of 95 elk had been exported from farms with CWD to Korea. These consisted
of 23 elk in 1994 originating from the so-called “source farm” in Canada, and 72
elk in 1997, which had been held in pre export quarantine at the “source
farm”.Based on export information of CWD suspected elk from Canada to Korea, CWD
surveillance program was initiated by the Ministry of Agriculture and Forestry
(MAF) in 2001.
All elks imported in 1997 were traced back, however elks imported in 1994
were impossible to identify. CWD control measures included stamping out of all
animals in the affected farm, and thorough cleaning and disinfection of the
premises. In addition, nationwide clinical surveillance of Korean native
cervids, and improved measures to ensure reporting of CWD suspect cases were
implemented.
Total of 9 elks were found to be affected. CWD was designated as a
notifiable disease under the Act for Prevention of Livestock Epidemics in 2002.
Additional CWD cases - 12 elks and 2 elks - were diagnosed in 2004 and
2005.
Since February of 2005, when slaughtered elks were found to be positive,
all slaughtered cervid for human consumption at abattoirs were designated as
target of the CWD surveillance program. Currently, CWD laboratory testing is
only conducted by National Reference Laboratory on CWD, which is the Foreign
Animal Disease Division (FADD) of National Veterinary Research and Quarantine
Service (NVRQS).
In July 2010, one out of 3 elks from Farm 1 which were slaughtered for the
human consumption was confirmed as positive. Consequently, all cervid – 54 elks,
41 Sika deer and 5 Albino deer – were culled and one elk was found to be
positive. Epidemiological investigations were conducted by Veterinary
Epidemiology Division (VED) of NVRQS in collaboration with provincial veterinary
services.
Epidemiologically related farms were found as 3 farms and all cervid at
these farms were culled and subjected to CWD diagnosis. Three elks and 5
crossbreeds (Red deer and Sika deer) were confirmed as positive at farm 2.
All cervids at Farm 3 and Farm 4 – 15 elks and 47 elks – were culled and
confirmed as negative.
Further epidemiological investigations showed that these CWD outbreaks were
linked to the importation of elks from Canada in 1994 based on circumstantial
evidences.
In December 2010, one elk was confirmed as positive at Farm 5.
Consequently, all cervid – 3 elks, 11 Manchurian Sika deer and 20 Sika deer –
were culled and one Manchurian Sika deer and seven Sika deer were found to be
positive. This is the first report of CWD in these sub-species of deer.
Epidemiological investigations found that the owner of the Farm 2 in CWD
outbreaks in July 2010 had co-owned the Farm 5.
In addition, it was newly revealed that one positive elk was introduced
from Farm 6 of Jinju-si Gyeongsang Namdo. All cervid – 19 elks, 15 crossbreed
(species unknown) and 64 Sika deer – of Farm 6 were culled, but all confirmed as
negative.
New studies on the heat resistance of hamster-adapted scrapie agent:
Threshold survival after ashing at 600°C suggests an inorganic template of
replication
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.
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 ;
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.
*** Infectious agent of sheep scrapie may persist in the environment for at
least 16 years ***
Gudmundur Georgsson1, Sigurdur Sigurdarson2 and Paul Brown3
Contamination of Plants with Prions Excreted in Urine and Feces
Under natural conditions, it is likely that the main source of prions in
the environment comes from secretory and excretory fluids, such as saliva,
urine, and feces. We and others have shown that PrPSc is released in these
fluids and excretions in various animal species (Gonzalez-Romero et al., 2008;
Haley et al., 2009, 2011; Maddison et al., 2010; Terry et al., 2011; Moda et
al., 2014). It has been estimated that the amount of infectious prions spread by
excreta during the animals’ lifespan could match or even surpass the quantity
present in the brain of a symptomatic individual (Tamgu¨ ney et al., 2009). To
study whether plant tissue can be contaminated by waste products excreted from
prion-infected hamsters and deer, leaves and roots were incubated with samples
of urine and feces and the presence of PrPSc analyzed by serial rounds of PMCA.
For these experiments, plant tissues were incubated for 1 hr with urine or feces
homogenates obtained either from 263K-infected hamsters or CWD-affected cervids.
This time was chosen because longer incubation with these biological fluids
affected the integrity of the plant tissue. After being thoroughly washed and
dried, PrPSc attached to leaves and roots was detected by PMCA. The results
clearly show that PrPSc was readily detectable after three or four rounds of
PMCA in samples of wheat grass leaves and roots exposed to both urine and feces
from 263K sick hamsters (Figure 3A) and CWD-affected cervids (Figure 3B).
Comparing these results with studies of the direct detection of PrPSc in urine
and feces (Figures 3A and 3B), it seems that the majority of PrPSc present in
these waste products was effectively attached to leaves and roots. No signal was
observed in plant tissue exposed to urine or feces coming from non-infected
hamsters.
Prions Bind to Living Plants
To investigate a more natural scenario for prion contamination of living
plants, we sprayed the leaves of wheat grass with a preparation containing 1%
263K hamster brain homogenate. Plants were let to grow for different times after
exposure, and PrPSc was detected in the leaves by PMCA in duplicates for each
time point. The results show that PrPSc was able to bind to leaves and remained
attached to the living plants for at least 49 days after exposure (Figure 4).
Considering that PrPSc signal was detectable normally in the second or third
round of PMCA without obvious trend in relation to time, we conclude that the
relative amount of PrPSc present in leaves did not appear to change
substantially over time. These data indicate that PrPSc can be retained in
living plants for at least several weeks after a simple contact with prion
contaminated materials, and PrPSc remains competent to drive prion replication.
DISCUSSION
This study shows that plants can efficiently bind prions contained in brain
extracts from diverse prion infected animals, including CWD-affected cervids.
PrPSc attached to leaves and roots from wheat grass plants remains capable of
seeding prion replication in vitro. Surprisingly, the small quantity of PrPSc
naturally excreted in urine and feces from sick hamster or cervids was enough to
efficiently contaminate plant tissue. Indeed, our results suggest that the
majority of excreted PrPSc is efficiently captured by plants’ leaves and roots.
Moreover, leaves can be contaminated by spraying them with a prion-containing
extract, and PrPSc remains detectable in living plants for as long as the study
was performed (several weeks). Remarkably, prion contaminated plants transmit
prion disease to animals upon ingestion, producing a 100% attack rate and
incubation periods not substantially longer than direct oral administration of
sick brain homogenates. Finally, an unexpected but exciting result was that
plants were able to uptake prions from contaminated soil and transport them to
aerial parts of the plant tissue. Although it may seem farfetched that plants
can uptake proteins from the soil and transport it to the parts above the
ground, there are already published reports of this phenomenon (McLaren et al.,
1960; Jensen and McLaren, 1960; Paungfoo-Lonhienne et al., 2008). The high
resistance of prions to degradation and their ability to efficiently cross
biological barriers mayplay a role in this process. The mechanism by which
plants bind, retain, uptake, and transport prions is unknown. Weare currently
studying the way in which prions interact with plants using purified,
radioactively labeled PrPSc to determine specificity of the interaction,
association constant, reversibility, saturation, movement, etc.
Epidemiological studies have shown numerous instances of scrapie or CWD
recurrence upon reintroduction of animals on pastures previously exposed to
prion-infected animals. Indeed, reappearance of scrapie has been documented
following fallow periods of up to 16 years (Georgsson et al., 2006), and
pastures were shown to retain infectious CWD prions for at least 2 years after
exposure (Miller et al., 2004). It is likely that the environmentally mediated
transmission of prion diseases depends upon the interaction of prions with
diverse elements, including soil, water, environmental surfaces, various
invertebrate animals, and plants.
However, since plants are such an important component of the environment
and also a major source of food for many animal species, including humans, our
results may have far-reaching implications for animal and human health.
Currently, the perception of the risk for animal-to-human prion transmission has
been mostly limited to consumption or exposure to contaminated meat; our results
indicate that plants might also be an important vector of transmission that
needs to be considered in risk assessment.
Tuesday, September 22, 2015
Host Determinants of Prion Strain Diversity Independent of Prion Protein
Genotype
Monday, August 31, 2015
Illinois Loosing Ground to Chronic Wasting Disease CWD cases mounting with
71 confirmed in 2015 and 538 confirmed cases to date
Friday, September 18, 2015
Michigan DNR honors Meridian Township for its CWD response, cooperation
Wednesday, September 16, 2015
*** WISCONSIN CAPTIVE CERVID INDUSTRY RUNNING WILD AND ON THE LOOSE RISKING
FURTHER SPREAD OF CWD ***
Monday, August 24, 2015
*** Ohio wildlife officials ramp up fight against fatal deer brain disease
after 17 more positive tests CWD ***
Wednesday, March 25, 2015
*** Chronic Wasting Disease CWD Cases Confirmed In New Mexico 2013 and 2014
UPDATE 2015 ***
Wednesday, March 18, 2015
*** Chronic Wasting Disease CWD Confirmed Texas Trans Pecos March 18, 2015
***
Thursday, September 24, 2015
TEXAS Hunters Asked to Submit Samples for Chronic Wasting Disease CWD TSE
Prion Testing
*** I cannot stress enough to all of you, for the sake of your family and
mine, before putting anything in the freezer, have those deer tested for CWD.
...terry
Tuesday, September 22, 2015
Host Determinants of Prion Strain Diversity Independent of Prion Protein
Genotype
Saturday, September 12, 2015
*** In utero transmission and tissue distribution of chronic wasting
disease-associated prions in free-ranging Rocky Mountain elk ***
Sunday, September 13, 2015
*** urine, feces, and chronic wasting disease cwd tse prion risk factors,
loading up the environment ***
Friday, August 28, 2015
*** Chronic Wasting Disease CWD TSE Prion Diagnostics and subclinical
infection ***
PRION 2015 ORAL AND POSTER CONGRESSIONAL ABSTRACTS
THANK YOU PRION 2015 TAYLOR & FRANCIS, Professor Chernoff, and
Professor Aguzzi et al, for making these PRION 2015 Congressional Poster and
Oral Abstracts available freely to the public. ...Terry S. Singeltary Sr.
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, Val erie 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 longe 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...
===============
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
Thursday, September 10, 2015
TSEAC FDA TSE PRION MAD COW CIRCUS AND TRAVELING ROAD SHOW (their
words)
25th Meeting of the Transmissible Spongiform Encephalopathies Advisory
Committee Food and Drug Administration Silver Spring, Maryland June 1, 2015
Saturday, September 05, 2015
Missouri Captive Cervid Industry, CWD TSE Prion, and Procrastinating for
Money, while mad deer and elk disease silently spreads
Saturday, August 15, 2015
Missouri Deer Owners Win Preliminary Legal Challenge from Judge Robert D. Schollmeyer blocking enforcement of new state regulations to help stop CWD in cervid from spreading
http://chronic-wasting-disease.blogspot.com/2015/08/missouri-deer-owners-win-preliminary.html
Tuesday, June 16, 2015
Missouri MDC changes deer hunting regs to help slow CWD
Wednesday, March 11, 2015
MDC reports 11 new cases of Chronic Wasting Disease CWD in Missouri deer
Monday, January 26, 2015
Missouri MDC reports two new cases of CWD found in Adair and Macon counties
Tuesday, December 09, 2014
Missouri MDC reports one new case of CWD, found in Adair County
Friday, October 17, 2014
Missouri Final action on Orders of Rule making Breeders and Big Game
Hunting Preserves
Thursday, September 11, 2014
Missouri Nixon's Veto Stands Overide Fails on Agriculture Legislation
How they voted: attempt to override veto of ag bill fails in the House
Thursday, May 01, 2014
Missouri DNR CWD prevention and captive cervid farming Update
Tuesday, March 26, 2013
CWD Missouri remains confined to Linn-Macon-County Core Area with four new
cases
Wednesday, January 23, 2013
Missouri sixth case CWD documented northwest Macon County
Tuesday, January 24, 2012
CWD found in two free-ranging deer from Macon County Missouri
Friday, February 26, 2010
Chronic wasting disease found in Missouri deer
Sunday, March 25, 2012
Three more cases of CWD found in free-ranging deer in Macon County
From: Terry S. Singeltary Sr.
Sent: Thursday, March 29, 2012 6:26 PM
To: warhovert@missouri.edu
Cc: abbottjm@missouri.edu ; waltermr@missouri.edu ;
John.McLaughlin@missouri.edu ; connerek@missouri.edu ; contact@dnr.mo.gov ;
Shelly.Witt@mda.mo.gov ; Animal.Health@mda.mo.gov ; acfa@mda.mo.gov ;
animalid@mda.mo.gov ; Linda.Hickam@mda.mo.gov
Subject: re-Missouri officials seek states' advice on chronic wasting
disease in deer
Thursday, May 31, 2012
Missouri MDC staff will provide information on five recently found cases of
CWD in free-ranging deer in northwest Macon County June 2, 2012
Wednesday, September 05, 2012
Missouri MDC seeks hunters’ help when processing harvested deer and
preventing CWD
Thursday, December 20, 2012
MISSOURI Initial CWD sampling test results available online from MDC so far
one adult buck has tested positive for the disease
Friday, October 21, 2011
Chronic Wasting Disease Found in Captive Deer Missouri
The Missouri Department of Agriculture discovers the state's first case of
CWD in a captive white-tailed deer.
Friday, February 26, 2010
Chronic wasting disease found in Missouri deer February 25, 2010
Chronic Wasting Disease Found in Captive Deer
The Missouri Departments of Agriculture, Conservation and Health and Senior
Services and the U.S. Department of Agriculture announced today that a captive
white-tailed deer in Linn County, Missouri has tested positive for Chronic
Wasting Disease (CWD). CWD is a neurological disease found in deer, elk and
moose.
"There is no evidence that CWD poses a risk to domestic animals or humans,"
said State Veterinarian Dr. Taylor Woods. "We have protocols in place to quickly
and effectively handle these situations."
The animal that tested positive for CWD was a white-tailed deer inspected
as part of the State's CWD surveillance and testing program. Preliminary tests
were conducted by the USDA National Veterinary Services Laboratory in Ames,
Iowa.
Upon receiving the confirmed CWD positive, Missouri's departments of
Agriculture, Conservation and Health and Senior Services initiated their CWD
Contingency Plan. The plan was developed in 2002 by the Cervid Health Committee,
a task force comprised of veterinarians, animal health officers and conservation
officers from USDA, MDA, MDC and DHSS working together to mitigate challenges
associated with CWD.
CWD is transmitted by live animal to animal contact or soil to animal
contact. The disease was first recognized in 1967 in captive mule deer in the
Colorado Division of Wildlife captive wildlife research facility in Fort
Collins, Colorado. CWD has been documented in deer and/or elk in Colorado,
Illinois, Kansas, Michigan, Minnesota, Montana, Nebraska, New Mexico, New York,
Oklahoma, South Dakota, Utah, Virginia, West Virginia, Wisconsin, and the
Canadian Provinces of Alberta and Saskatchewan. There has been no evidence that
the disease can be transmitted to humans.
"Missouri's proactive steps to put a testing protocol in place and create a
contingency plan years ago is proving beneficial. We are in a solid position to
follow pre-established steps to ensure Missouri's valuable whitetail deer
resource remains healthy and strong," said Jason Sumners Missouri's Deer
Biologist.
For more information regarding CWD, please contact Dr. Taylor Woods at
(573) 751-3377.
Friday, September 20, 2013
*** Missouri State records show gaps in oversight of captive deer farms,
ranches ***
with sad regards, terry
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