WVDNR News: Further Actions Taken to Combat CWD of Deer in West Virginia
Wednesday, July 22, 2015 8:09 AM
Subject: WVDNR News: Further Actions Taken to Combat CWD of Deer in West
Virginia
Further Actions Taken to Combat CWD of Deer in West Virginia
SOUTH CHARLESTON, W.Va. –“As part of our agency’s ongoing management
efforts to slow the spread of Chronic Wasting Disease (CWD), a larger portion of
the Eastern Panhandle of West Virginia has been added to the current area where
artificial supplemental feeding and baiting of deer is prohibited,” said Robert
Fala, Director of the West Virginia Division of Natural Resources (DNR).
Effective July 1, 2015, the area includes Berkeley, Grant, Hampshire,
Hardy, Jefferson, Mineral and Morgan counties. Current research indicates that
supplemental feeding and baiting of deer increases the chance of disease
transmission far above the normal clustering of deer on natural and agricultural
feeding areas. Lowering encounter rates between infected and non-infected
animals by prohibiting artificial supplemental feeding and baiting are generally
accepted management practices for slowing the spread of an infectious disease
among wildlife.
Initiating these prohibitions is a major tool used by other states
combating CWD. In these seven Eastern Panhandle counties it is illegal to bait
or feed deer, which includes minerals and other edible enticements. Song and
insectivorous birds may be fed, provided that such feeding shall not cause, or
be done in a manner that would be reasonably anticipated to cause, a
congregation of deer or other wildlife.
“The expansion of the West Virginia CWD Containment Area follows similar
expansions of disease management areas in Virginia and Pennsylvania,” Director
Fala said.
At a recent meeting hosted by West Virginia DNR at Cacapon Resort State
Park, wildlife agency staff tasked with addressing CWD in their respective
states of Maryland, Virginia, Pennsylvania, New York and Ohio shared information
regarding CWD and discussed ways to coordinate CWD management efforts on a
regional basis.
“This information exchange between states is especially important with the
current location of known CWD infected deer located in close proximity across
the states of Maryland, Pennsylvania, Virginia and West Virginia,” said Director
Fala.
Deer hunters are reminded that dead deer or their parts may not be
transported beyond the boundary of Hampshire, Hardy and Morgan counties except
for the following: meat that has been boned out, quarters or other portions of
meat with no part of the spinal column or head attached, cleaned hide with no
head attached, clean skull plate (no meat or tissue attached) with antlers
attached, antlers with no meat or tissue attached, and finished taxidermy
mounts. Hunters may transport deer carcasses that were not killed inside the
containment area through the containment area.
CWD has now been detected in a total of 179 deer in Hampshire County and
four deer in Hardy County. The DNR will continue to update management actions
designed to control the spread of this disease, prevent further introduction of
the disease, and possibly eliminate the disease from the state as information
from deer testing within West Virginia is gathered and scientists across the
country provide more information on how to combat CWD in white-tailed deer.
For additional information on deer baiting and feeding prohibitions and
deer carcass transport restrictions please see the 2015-2016 Hunting and
Trapping Regulations Summary available at DNR offices and license agents or
visit www.wvdnr.gov.
**DNR**
West Virginia Division of Natural Resources
www.wvdnr.gov
Earl Ray Tomblin, Governor
Bob Fala, Director
News Release: July 22, 2015
Facebook: www.facebook.com/wildlifewv Twitter: www.twitter.com/wildlifewv
Hoy Murphy, Public Information Officer 304-957-9365
hoy.r.murphy@wv.gov
Contact: Paul Johansen, Chief, Wildlife Resources Section 304-558-2771
DNR.Wildlife@wv.gov
Sunday, June 29, 2014
Chronic wasting disease spreads in West Virginia
Friday, February 28, 2014
West Virginia Deer farming bill passes in House unanimously
see case incident of cwd in West Virginia
animal protein in feed for cervid is another source for CWD TSE prion
disease. please see ;
Oral transmission and early lymphoid tropism of chronic wasting disease
PrPres in mule deer fawns (Odocoileus hemionus )
Christina J. Sigurdson1, Elizabeth S. Williams2, Michael W. Miller3, Terry
R. Spraker1,4, Katherine I. O'Rourke5 and Edward A. Hoover1
Department of Pathology, College of Veterinary Medicine and Biomedical
Sciences, Colorado State University, Fort Collins, CO 80523- 1671, USA1
Department of Veterinary Sciences, University of Wyoming, 1174 Snowy Range Road,
University of Wyoming, Laramie, WY 82070, USA 2 Colorado Division of Wildlife,
Wildlife Research Center, 317 West Prospect Road, Fort Collins, CO 80526-2097,
USA3 Colorado State University Veterinary Diagnostic Laboratory, 300 West Drake
Road, Fort Collins, CO 80523-1671, USA4 Animal Disease Research Unit,
Agricultural Research Service, US Department of Agriculture, 337 Bustad Hall,
Washington State University, Pullman, WA 99164-7030, USA5
Author for correspondence: Edward Hoover.Fax +1 970 491 0523. e-mail
ehoover@lamar.colostate.edu
Mule deer fawns (Odocoileus hemionus) were inoculated orally with a brain
homogenate prepared from mule deer with naturally occurring chronic wasting
disease (CWD), a prion-induced transmissible spongiform encephalopathy. Fawns
were necropsied and examined for PrP res, the abnormal prion protein isoform, at
10, 42, 53, 77, 78 and 80 days post-inoculation (p.i.) using an
immunohistochemistry assay modified to enhance sensitivity. PrPres was detected
in alimentary-tract-associated lymphoid tissues (one or more of the following:
retropharyngeal lymph node, tonsil, Peyer's patch and ileocaecal lymph node) as
early as 42 days p.i. and in all fawns examined thereafter (53 to 80 days p.i.).
No PrPres staining was detected in lymphoid tissue of three control fawns
receiving a control brain inoculum, nor was PrPres detectable in neural tissue
of any fawn. PrPres-specific staining was markedly enhanced by sequential tissue
treatment with formic acid, proteinase K and hydrated autoclaving prior to
immunohistochemical staining with monoclonal antibody F89/160.1.5. These results
indicate that CWD PrP res can be detected in lymphoid tissues draining the
alimentary tract within a few weeks after oral exposure to infectious prions and
may reflect the initial pathway of CWD infection in deer. The rapid infection of
deer fawns following exposure by the most plausible natural route is consistent
with the efficient horizontal transmission of CWD in nature and enables
accelerated studies of transmission and pathogenesis in the native
species.
snip...
These results indicate that mule deer fawns develop detectable PrP res
after oral exposure to an inoculum containing CWD prions. In the earliest
post-exposure period, CWD PrPres was traced to the lymphoid tissues draining the
oral and intestinal mucosa (i.e. the retropharyngeal lymph nodes, tonsil, ileal
Peyer's patches and ileocaecal lymph nodes), which probably received the highest
initial exposure to the inoculum. Hadlow et al. (1982) demonstrated scrapie
agent in the tonsil, retropharyngeal and mesenteric lymph nodes, ileum and
spleen in a 10-month-old naturally infected lamb by mouse bioassay. Eight of
nine sheep had infectivity in the retropharyngeal lymph node. He concluded that
the tissue distribution suggested primary infection via the gastrointestinal
tract. The tissue distribution of PrPres in the early stages of infection in the
fawns is strikingly similar to that seen in naturally infected sheep with
scrapie. These findings support oral exposure as a natural route of CWD
infection in deer and support oral inoculation as a reasonable exposure route
for experimental studies of CWD.
snip...
Susceptibility of European Red Deer (Cervus elaphus elaphus) to Alimentary
Challenge with Bovine Spongiform Encephalopathy
Abstract
European red deer (Cervus elaphus elaphus) are susceptible to the agent of
bovine spongiform encephalopathy, one of the transmissible spongiform
encephalopathies, when challenged intracerebrally but their susceptibility to
alimentary challenge, the presumed natural route of transmission, is unknown. To
determine this, eighteen deer were challenged via stomach tube with a large dose
of the bovine spongiform encephalopathy agent and clinical signs, gross and
histological lesions, presence and distribution of abnormal prion protein and
the attack rate recorded. Only a single animal developed clinical disease, and
this was acute with both neurological and respiratory signs, at 1726 days post
challenge although there was significant (27.6%) weight loss in the preceding
141 days. The clinically affected animal had histological lesions of vacuolation
in the neuronal perikaryon and neuropil, typical of transmissible spongiform
encephalopathies. Abnormal prion protein, the diagnostic marker of transmissible
encephalopathies, was primarily restricted to the central and peripheral nervous
systems although a very small amount was present in tingible body macrophages in
the lymphoid patches of the caecum and colon. Serial protein misfolding cyclical
amplification, an in vitro ultra-sensitive diagnostic technique, was positive
for neurological tissue from the single clinically diseased deer. All other
alimentary challenged deer failed to develop clinical disease and were negative
for all other investigations. These findings show that transmission of bovine
spongiform encephalopathy to European red deer via the alimentary route is
possible but the transmission rate is low. Additionally, when deer carcases are
subjected to the same regulations that ruminants in Europe with respect to the
removal of specified offal from the human food chain, the zoonotic risk of
bovine spongiform encephalopathy, the cause of variant Creutzfeldt-Jakob
disease, from consumption of venison is probably very low.
snip...
Discussion This investigation resulted in the first and only known case, to
date, of clinical disease or accumulation of abnormal PrPd in any cervid species
due to oral challenge with BSE. The increase in incubation period compared to
European red deer challenged with BSE intra-cerebrally (1060 days) [33] compared
to oral challenge (1727 days) is approximately 60% and similar to the
differences observed in incubation periods for sheep or goats when challenged
with TSE agents by these two routes [40,41]. The neurological clinical signs
observed could be broadly related to the spongiform encephalopathy and the
accumulation of PrPd in that the restlessness, stereotypic head movements and
pacing may be due to compromise of the nucleus accumbens [42], found in the
striatum, and the laboured breathing due to the lesions in the medulla, where
the respiratory centre is located [43]. Alternatively, the laboured and audible
mouth breathing may have been due to, or contributed to by, compromise of either
of the recurrent laryngeal nerves resulting in some degree of laryngeal
paralysis but we were unable to determine this. Apart from the gradual loss of
body weight, the speed of onset of clinical signs and progression was very rapid
but animal welfare requirements precluded any further longitudinal study of
these. The clinical signs described for this animal are broadly similar to those
reported for clinical BSE in European red deer challenged via the intracerebral
route [33], clinical cases of CWD in deer [44] and clinical cases of BSE in
cattle [45].
snip...see full text ;
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
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...
Susceptibility of European Red Deer (Cervus elaphus elaphus) to Alimentary
Challenge with Bovine Spongiform Encephalopathy
Abstract
European red deer (Cervus elaphus elaphus) are susceptible to the agent of
bovine spongiform encephalopathy, one of the transmissible spongiform
encephalopathies, when challenged intracerebrally but their susceptibility to
alimentary challenge, the presumed natural route of transmission, is unknown. To
determine this, eighteen deer were challenged via stomach tube with a large dose
of the bovine spongiform encephalopathy agent and clinical signs, gross and
histological lesions, presence and distribution of abnormal prion protein and
the attack rate recorded. Only a single animal developed clinical disease, and
this was acute with both neurological and respiratory signs, at 1726 days post
challenge although there was significant (27.6%) weight loss in the preceding
141 days. The clinically affected animal had histological lesions of vacuolation
in the neuronal perikaryon and neuropil, typical of transmissible spongiform
encephalopathies. Abnormal prion protein, the diagnostic marker of transmissible
encephalopathies, was primarily restricted to the central and peripheral nervous
systems although a very small amount was present in tingible body macrophages in
the lymphoid patches of the caecum and colon. Serial protein misfolding cyclical
amplification, an in vitro ultra-sensitive diagnostic technique, was positive
for neurological tissue from the single clinically diseased deer. All other
alimentary challenged deer failed to develop clinical disease and were negative
for all other investigations. These findings show that transmission of bovine
spongiform encephalopathy to European red deer via the alimentary route is
possible but the transmission rate is low. Additionally, when deer carcases are
subjected to the same regulations that ruminants in Europe with respect to the
removal of specified offal from the human food chain, the zoonotic risk of
bovine spongiform encephalopathy, the cause of variant Creutzfeldt-Jakob
disease, from consumption of venison is probably very low.
snip...
Discussion This investigation resulted in the first and only known case, to
date, of clinical disease or accumulation of abnormal PrPd in any cervid species
due to oral challenge with BSE. The increase in incubation period compared to
European red deer challenged with BSE intra-cerebrally (1060 days) [33] compared
to oral challenge (1727 days) is approximately 60% and similar to the
differences observed in incubation periods for sheep or goats when challenged
with TSE agents by these two routes [40,41]. The neurological clinical signs
observed could be broadly related to the spongiform encephalopathy and the
accumulation of PrPd in that the restlessness, stereotypic head movements and
pacing may be due to compromise of the nucleus accumbens [42], found in the
striatum, and the laboured breathing due to the lesions in the medulla, where
the respiratory centre is located [43]. Alternatively, the laboured and audible
mouth breathing may have been due to, or contributed to by, compromise of either
of the recurrent laryngeal nerves resulting in some degree of laryngeal
paralysis but we were unable to determine this. Apart from the gradual loss of
body weight, the speed of onset of clinical signs and progression was very rapid
but animal welfare requirements precluded any further longitudinal study of
these. The clinical signs described for this animal are broadly similar to those
reported for clinical BSE in European red deer challenged via the intracerebral
route [33], clinical cases of CWD in deer [44] and clinical cases of BSE in
cattle [45].
snip...see full text ;
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
The TSE prion disease survives ashing to 600 degrees celsius, that’s around
1112 degrees farenheit.
you cannot cook the TSE prion disease out of meat.
you can take the ash and mix it with saline and inject that ash into a
mouse, and the mouse will go down with TSE.
Prion Infected Meat-and-Bone Meal Is Still Infectious after Biodiesel
Production as well.
the TSE prion agent also survives Simulated Wastewater Treatment Processes.
IN fact, you should also know that the TSE Prion agent will survive in the
environment for years, if not decades.
you can bury it and it will not go away.
The TSE agent is capable of infected your water table i.e. Detection of
protease-resistant cervid prion protein in water from a CWD-endemic area.
it’s not your ordinary pathogen you can just cook it out and be done with.
that’s what’s so worrisome about Iatrogenic mode of transmission, a simple
autoclave will not kill this TSE prion agent.
New studies on the heat resistance of hamster-adapted scrapie agent:
Threshold survival after ashing at 600°C suggests an inorganic template of
replication
The infectious agents responsible for transmissible spongiform
encephalopathy (TSE) are notoriously resistant to most physical and chemical
methods used for inactivating pathogens, including heat. It has long been
recognized, for example, that boiling is ineffective and that higher
temperatures are most efficient when combined with steam under pressure (i.e.,
autoclaving). As a means of decontamination, dry heat is used only at the
extremely high temperatures achieved during incineration, usually in excess of
600°C. It has been assumed, without proof, that incineration totally inactivates
the agents of TSE, whether of human or animal origin.
Prion Infected Meat-and-Bone Meal Is Still Infectious after Biodiesel
Production
Histochemical analysis of hamster brains inoculated with the solid residue
showed typical spongiform degeneration and vacuolation. Re-inoculation of these
brains into a new cohort of hamsters led to onset of clinical scrapie symptoms
within 75 days, suggesting that the specific infectivity of the prion protein
was not changed during the biodiesel process. The biodiesel reaction cannot be
considered a viable prion decontamination method for MBM, although we observed
increased survival time of hamsters and reduced infectivity greater than 6 log
orders in the solid MBM residue. Furthermore, results from our study compare for
the first time prion detection by Western Blot versus an infectivity bioassay
for analysis of biodiesel reaction products. We could show that biochemical
analysis alone is insufficient for detection of prion infectivity after a
biodiesel process.
Detection of protease-resistant cervid prion protein in water from a
CWD-endemic area
The data presented here demonstrate that sPMCA can detect low levels of
PrPCWD in the environment, corroborate previous biological and experimental data
suggesting long term persistence of prions in the environment2,3 and imply that
PrPCWD accumulation over time may contribute to transmission of CWD in areas
where it has been endemic for decades. This work demonstrates the utility of
sPMCA to evaluate other environmental water sources for PrPCWD, including
smaller bodies of water such as vernal pools and wallows, where large numbers of
cervids congregate and into which prions from infected animals may be shed and
concentrated to infectious levels.
A Quantitative Assessment of the Amount of Prion Diverted to Category 1
Materials and Wastewater During Processing
Keywords:Abattoir;bovine spongiform encephalopathy;QRA;scrapie;TSE
In this article the development and parameterization of a quantitative
assessment is described that estimates the amount of TSE infectivity that is
present in a whole animal carcass (bovine spongiform encephalopathy [BSE] for
cattle and classical/atypical scrapie for sheep and lambs) and the amounts that
subsequently fall to the floor during processing at facilities that handle
specified risk material (SRM). BSE in cattle was found to contain the most oral
doses, with a mean of 9864 BO ID50s (310, 38840) in a whole carcass compared to
a mean of 1851 OO ID50s (600, 4070) and 614 OO ID50s (155, 1509) for a sheep
infected with classical and atypical scrapie, respectively. Lambs contained the
least infectivity with a mean of 251 OO ID50s (83, 548) for classical scrapie
and 1 OO ID50s (0.2, 2) for atypical scrapie. The highest amounts of infectivity
falling to the floor and entering the drains from slaughtering a whole carcass
at SRM facilities were found to be from cattle infected with BSE at rendering
and large incineration facilities with 7.4 BO ID50s (0.1, 29), intermediate
plants and small incinerators with a mean of 4.5 BO ID50s (0.1, 18), and
collection centers, 3.6 BO ID50s (0.1, 14). The lowest amounts entering drains
are from lambs infected with classical and atypical scrapie at intermediate
plants and atypical scrapie at collection centers with a mean of 3 × 10−7 OO
ID50s (2 × 10−8, 1 × 10−6) per carcass. The results of this model provide key
inputs for the model in the companion paper published here.
*** Infectious agent of sheep scrapie may persist in the environment for at
least 16 years***
Gudmundur Georgsson1, Sigurdur Sigurdarson2 and Paul Brown3
Longitudinal Detection of Prion Shedding in Saliva and Urine by
CWD-Infected Deer by RT-QuIC
Davin M. Henderson1, Nathaniel D. Denkers1, Clare E. Hoover1, Nina
Garbino1, Candace K. Mathiason1 and Edward A. Hoover1# + Author
Affiliations
1Prion Research Center, Department of Microbiology, Immunology, and
Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado
State University, Fort Collins, CO 80523 ABSTRACT Chronic Wasting Disease (CWD)
is an emergent, rapidly spreading prion disease of cervids. Shedding of
infectious prions in saliva and urine is thought to be an important factor in
CWD transmission. To help elucidate this issue, we applied an in vitro
amplification assay to determine the onset, duration, and magnitude of prion
shedding in longitudinally collected saliva and urine samples from CWD-exposed
white-tailed deer. We detected prion shedding as early as 3 months after CWD
exposure and sustained shedding throughout the disease course. We estimated that
a 50% lethal dose (LD50) for cervidized transgenic mice would be contained in 1
ml of infected deer saliva or 10 ml or urine. Given the average course of
infection and daily production of these body fluids, an infected deer would shed
thousands of prion infectious dosesover the course of CWD infection. The direct
and indirect environmental impact of this magnitude of prion shedding for cervid
and non-cervid species is surely significant.
Importance: Chronic wasting disease (CWD) is an emerging and uniformly
fatal prion disease affecting free ranging deer and elk and now recognized in 22
United States and 2 C anadian Provinces. It is unique among prion diseases in
that it is transmitted naturally though wild populations. A major hypothesis for
CWD's florid spread is that prions are shed in excreta and transmitted via
direct or indirect environmental contact. Here we use a rapid in vitro assay to
show that infectious doses of CWD prions are in fact shed throughout the
multi-year disease course in deer. This finding is an important advance in
assessing the risks posed by shed CWD prions to animals as well as humans.
FOOTNOTES
↵#To whom correspondence should be addressed: Edward A. Hoover, Prion
Research Center, Department of Microbiology, Immunology and Pathology, Colorado
State University, Fort Collins, Colorado, US Email: edward.hoover@colostate.edu
Approximately 4,200 fawns, defined as deer under 1 year of age, were
sampled from the eradication zone over the last year. The majority of fawns
sampled were between the ages of 5 to 9 months, though some were as young as 1
month. Two of the six fawns with CWD detected were 5 to 6 months old. All six of
the positive fawns were taken from the core area of the CWD eradication zone
where the highest numbers of positive deer have been identified.
"This is the first intensive sampling for CWD in fawns anywhere," said Dr.
Julie Langenberg, Department of Natural Resources wildlife veterinarian, "and we
are trying to learn as much as we can from these data".
Saturday, February 04, 2012
Wisconsin 16 MONTH age limit on testing dead deer Game Farm CWD Testing
Protocol Needs To Be Revised
Articles of Significant Interest Selected from This Issue by the Editors
Next Section Prions in the Blood of Infected Hosts: Early and Persistent Prions
circulate in the blood of prion-infected hosts, including humans with variant
Creutzfeldt-Jakob disease. Determining the parameters of blood-borne prions
during the long asymptomatic phase of disease characteristic of all prion
diseases has been a long-standing problem in prion biology. Elder et. al (p.
7421–7424) have demonstrated amyloid formation, a biomarker for prions, in the
blood of prion-infected rodent and cervid hosts as early as 15 minutes
post-mucosal or -intravenous infection. This prionemia persists throughout the
disease course, indicating a role for hematogenous prions throughout the
preclinical stage of illness.
***Immediate and Ongoing Detection of Prions in the Blood of Hamsters and
Deer following Oral, Nasal, or Blood Inoculations
Alan M. Eldera, Davin M. Hendersona, Amy V. Nallsa, Edward A. Hoovera,
Anthony E. Kincaidb,c, Jason C. Bartzb and Candace K. Mathiasona aDepartment of
Microbiology, Immunology and Pathology, Colorado State University, Fort Collins,
Colorado, USA bMedical Microbiology and Immunology, Creighton University, Omaha,
Nebraska, USA cDepartment of Pharmacy Sciences, Creighton University, Omaha,
Nebraska, USA S. Perlman, Editor + Author Affiliations
what about CWD infection rates on some of these game farms ???
CHRONIC WASTING DISEASE CWD WISCONSIN Almond Deer (Buckhorn Flats)
FarmUpdate DECEMBER 2011The CWD infection rate was nearly 80%, the highest ever
in a North American captive herd. RECOMMENDATION: That the Board approve the
purchase of 80acres of land for $465,000 for the Statewide Wildlife Habitat
Program inPortage 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). The owners of the
quarantined herd have entered into a fence maintenance agreement with the Iowa
Department of Agriculture and Land Stewardship,which requires the owners to
maintain the 8’ foot perimeter fence around the herd premises for five years
after the depopulation was complete and the premises had been cleaned and
disinfected CWD is a progressive, fatal, degenerative neurological disease of
farmed and free-ranging deer, elk, and moose. There is no known treatment or
vaccine for CWD. CWD is not a disease that affects humans.On July 18, 2012, USDA
Animal and Plant Health Inspection Service’s (APHIS)National Veterinary Services
Lab in Ames, IA confirmed that a male whitetail deer harvested from a hunting
preserve in southeast IA was positive for CWD. An investigation revealed that
this animal had just been introduced into the hunting preserve from the
above-referenced captive deer herd in north-central Iowa.The captive deer herd
was immediately quarantined to prevent the spread of CWD. The herd has remained
in quarantine until its depopulation on August 25 to 27, 2014.The Iowa
Department of Agriculture and Land Stewardship participated in a joint operation
to depopulate the infected herd with USDA Veterinary Services, which was the
lead agency, and USDA Wildlife Services.Federal indemnity funding became
available in 2014. USDA APHIS appraised the captive deer herd of 376 animals at
that time, which was before depopulation and testing, at $1,354,250. At that
time a herd plan was developed with the owners and officials from USDA and the
Iowa Department of Agriculture and Land Stewardship.Once the depopulation was
complete and the premises had been cleaned and disinfected, indemnity of
$917,100.00 from the USDA has been or will be paid to the owners as compensation
for the 356 captive deer depopulated.The Iowa Department of Agriculture and Land
Stewardship operates a voluntary CWD program for farms that sell live animals.
Currently 145 Iowa farms participate in the voluntary program. The
above-referenced captive deer facility left the voluntary CWD program prior to
the discovery of the disease as they had stopped selling live animals. All deer
harvested in a hunting preserve must be tested for CWD. -30-
*** 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 beencut 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.
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
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.
*** LATE-BREAKING ABSTRACTS PRION 2015 CONFERENCE ***
O18
Zoonotic Potential of CWD Prions
Liuting Qing1, Ignazio Cali1,2, Jue Yuan1, Shenghai Huang3, Diane Kofskey1,
Pierluigi Gambetti1, Wenquan Zou1, Qingzhong Kong1 1Case Western Reserve
University, Cleveland, Ohio, USA, 2Second University of Naples, Naples, Italy,
3Encore Health Resources, Houston, Texas, USA
Chronic wasting disease (CWD) is a widespread and expanding prion disease
in free-ranging and captive cervid species in North America. The zoonotic
potential of CWD prions is a serious public health concern. Current literature
generated with in vitro methods and in vivo animal models (transgenic mice,
macaques and squirrel monkeys) reports conflicting results. The susceptibility
of human CNS and peripheral organs to CWD prions remains largely unresolved. In
our earlier bioassay experiments using several humanized transgenic mouse lines,
we detected protease-resistant PrPSc in the spleen of two out of 140 mice that
were intracerebrally inoculated with natural CWD isolates, but PrPSc was not
detected in the brain of the same mice. Secondary passages with such
PrPSc-positive CWD-inoculated humanized mouse spleen tissues led to efficient
prion transmission with clear clinical and pathological signs in both humanized
and cervidized transgenic mice. Furthermore, a recent bioassay with natural CWD
isolates in a new humanized transgenic mouse line led to clinical prion
infection in 2 out of 20 mice. These results indicate that the CWD prion has the
potential to infect human CNS and peripheral lymphoid tissues and that there
might be asymptomatic human carriers of CWD infection.
==================
***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
The propensity for trans-species prion transmission is related to the
structural characteristics of the enciphering and heterologous PrP, but the
exact mechanism remains mostly mysterious. Studies of the effects of primary or
tertiary prion protein structures on trans-species prion transmission have
relied primarily upon animal bioassays, making the influence of prion protein
structure vs. host co-factors (e.g. cellular constituents, trafficking, and
innate immune interactions) difficult to dissect. As an alternative strategy, we
used real-time quakinginduced conversion (RT-QuIC) to investigate trans-species
prion conversion.
To assess trans-species conversion in the RT-QuIC system, we compared
chronic wasting disease (CWD) and bovine spongiform encephalopathy (BSE) prions,
as well as feline CWD (fCWD) and feline spongiform encephalopathy (FSE). Each
prion was seeded into each host recombinant PrP (full-length rPrP of
white-tailed deer, bovine or feline). We demonstrated that fCWD is a more
efficient seed for feline rPrP than for white-tailed deer rPrP, which suggests
adaptation to the new host.
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.***
================
Willingham, Erin McNulty, Kelly Anderson, Jeanette Hayes-Klug, Amy Nalls,
and Candace Mathiason Colorado State University; Fort Collins, CO USA
Chronic wasting disease (CWD) is the transmissible spongiform
encephalopathy (TSE), of free-ranging and captive cervids (deer, elk and moose).
The presence of infectious prions in the tissues, bodily fluids and
environments of clinical and preclinical CWD-infected animals is thought to
account for its high transmission efficiency. Recently it has been recognized
that mother to offspring transmission may contribute to the facile transmission
of some TSEs. Although the mechanism behind maternal transmission is not yet
known, the extended asymptomatic TSE carrier phase (lasting years to decades)
suggests that it may have implications in the spread of prions.
Placental trafficking and/or secretion in milk are 2 means by which
maternal prion transmission may occur. In these studies we explore these avenues
during early and late infection using a transgenic mouse model expressing cervid
prion protein. Na€ıve and CWD-infected dams were bred at both timepoints, and
were allowed to bear and raise their offspring. Milk was collected from the dams
for prion analysis, and the offspring were observed for TSE disease progression.
Terminal tissues harvested from both dams and offspring were analyzed for
prions.
We have demonstrated that
(1) CWDinfected TgCerPRP females successfully breed and bear offspring, and
(2) the presence of PrPCWD in reproductive and mammary tissue from
CWD-infected dams.
We are currently analyzing terminal tissue harvested from offspring born to
CWD-infected dams for the detection of PrPCWD and amplification competent
prions. These studies will provide insight into the potential mechanisms and
biological significance associated with mother to offspring transmission of
TSEs.
==============
P.157: Uptake of prions into plants
Christopher Johnson1, Christina Carlson1, Matthew Keating1,2, Nicole
Gibbs1, Haeyoon Chang1, Jamie Wiepz1, and Joel Pedersen1 1USGS National Wildlife
Health Center; Madison, WI USA; 2University of Wisconsin - Madison; Madison, WI
USA
Soil may preserve chronic wasting disease (CWD) and scrapie infectivity in
the environment, making consumption or inhalation of soil particles a plausible
mechanism whereby na€ıve animals can be exposed to prions. Plants are known to
absorb a variety of substances from soil, including whole proteins, yet the
potential for plants to take up abnormal prion protein (PrPTSE) and preserve
prion infectivity is not known. In this study, we assessed PrPTSE uptake into
roots using laser scanning confocal microscopy with fluorescently tagged PrPTSE
and we used serial protein misfolding cyclic amplification (sPMCA) and detect
and quantify PrPTSE levels in plant aerial tissues. Fluorescence was identified
in the root hairs of the model plant Arabidopsis thaliana, as well as the crop
plants alfalfa (Medicago sativa), barley (Hordeum vulgare) and tomato (Solanum
lycopersicum) upon exposure to tagged PrPTSE but not a tagged control
preparation. Using sPMCA, we found evidence of PrPTSE in aerial tissues of A.
thaliana, alfalfa and maize (Zea mays) grown in hydroponic cultures in which
only roots were exposed to PrPTSE. Levels of PrPTSE in plant aerial tissues
ranged from approximately 4 £ 10 ¡10 to 1 £ 10 ¡9 g PrPTSE g ¡1 plant dry weight
or 2 £ 105 to 7 £ 106 intracerebral ID50 units g ¡1 plant dry weight. Both stems
and leaves of A. thaliana grown in culture media containing prions are
infectious when intracerebrally-injected into mice. ***Our results suggest that
prions can be taken up by plants and that contaminated plants may represent a
previously unrecognized risk of human, domestic species and wildlife exposure to
prions.
===========
***Our results suggest that prions can be taken up by plants and that
contaminated plants may represent a previously unrecognized risk of human,
domestic species and wildlife exposure to prions.***
SEE ;
Friday, May 15, 2015
Grass Plants Bind, Retain, Uptake, and Transport Infectious Prions
Report
============
P.19: Characterization of chronic wasting disease isolates from freeranging
deer (Odocoileus sp) in Alberta and Saskatchewan, Canada
Camilo Duque Velasquez1, Chiye Kim1, Nathalie Daude1, Jacques van der
Merwe1, Allen Herbst1, Trent Bollinger2, Judd Aiken1, and Debbie McKenzie1
1Centre for Prions and Protein Folding Diseases; University of Alberta;
Edmonton, Canada; 2Western College of Veterinary Medicine; University of
Saskatchewan; Saskatoon, Canada
Chronic wasting disease (CWD) is an emerging prion disease of free ranging
and captive species of Cervidae. In North America, CWD is enzootic in some wild
cervid populations and can circulate among different deer species. The
contagious nature of CWD prions and the variation of cervid PRNP alleles, which
influence host susceptibility, can result in the emergence and adaptation of
different CWD strains. These strains may impact transmission host range, disease
diagnosis, spread dynamics and efficacy of potential vaccines. We are
characterizing different CWD agents by biochemical analysis of the PrPCWD
conformers, propagation in vitro cell assays1 and by comparing transmission
properties and neuropathology in Tg33 (Q95G96) and Tg60 (Q95S96) mice.2 Although
Tg60 mice expressing S96- PrPC have been shown resistant to CWD infectivity from
various cervid species,2,3
***these transgenic mice are susceptible to H95 C CWD, a CWD strain derived
from experimental infection of deer expressing H95G96-PrPC. The diversity of
strains present in free-ranging mule deer (Odocoileus hemionus) and white-tailed
deer (Odocoileus virginianus) from Alberta and Saskatchewan is being determined
and will allow us to delineate the properties of CWD agents circulating in CWD
enzootic cervid populations of Canada.
References
1. van der Merwe J, Aiken J, Westaway D, McKenzie D. The standard scrapie
cell assay: Development, utility and prospects. Viruses 2015; 7(1):180–198;
PMID:25602372; http://dx.doi.org/10.3390/v7010180
2. Meade-White K, Race B, Trifilo M, Bossers A, Favara C, Lacasse R, Miller
M, Williams E, Oldstone M, Race R, Chesebro B. Resistance to chronic wasting
disease in transgenic mice expressing a naturally occurring allelic variant of
deer prion protein. J Virol 2007; 81(9):4533–4539; PMID: 17314157; http://dx. doi.org/10.1128/JVI.02762-06
3. Race B, Meade-White K, Miller MW, Fox KA, Chesebro B. In vivo comparison
of chronic wasting disease infectivity from deer with variation at prion protein
residue 96. J Virol 2011; 85(17):9235–9238; PMID: 21697479; http://dx.doi.org/10.1128/JVI.00790-11
=========
***these transgenic mice are susceptible to H95 C CWD, a CWD strain derived
from experimental infection of deer expressing H95G96-PrPC.
==========
P.136: Mother to offspring transmission of CWD—Detection in fawn tissues
using the QuIC assay
Amy Nalls, Erin McNulty, Clare Hoover, Jeanette Hayes-Klug, Kelly Anderson,
Edward Hoover, and Candace Mathiason Colorado State University; Fort Collins, CO
USA
To investigate the role mother to offspring transmission plays in chronic
wasting disease (CWD), we have employed a small, polyestrous breeding, indoor
maintainable cervid model, the Reeves’ muntjac deer. Muntjac doe were inoculated
with CWD and tested positive by lymphoid biopsy at 4 months post inoculation.
From these CWD-infected doe, we obtained 3 viable fawns. These fawns tested
IHC-positive for CWD by lymphoid biopsy as early as 40 d post birth, and all
have been euthanized due to clinical disease at 31, 34 and 59 months post birth.
The QuIC assay demonstrates sensitivity and specificity in the detection of
conversion competent prions in peripheral IHC-positive tissues including tonsil,
mandibular, partotid, retropharyngeal, and prescapular lymph nodes, adrenal
gland, spleen and liver. In summary, using the muntjac deer model, we have
demonstrated CWD clinical disease in offspring born to CWD-infected doe and
found that the QuIC assay is an effective tool in the detection of prions in
peripheral tissues. ***Our findings demonstrate that transmission of prions from
mother to offspring can occur, and may be underestimated for all prion
diseases.
===============
***Our findings demonstrate that transmission of prions from mother to
offspring can occur, and may be underestimated for all prion diseases.
===============
98 | Veterinary Record | January 24, 2015
EDITORIAL
Scrapie: a particularly persistent pathogen
Cristina Acín
Resistant prions in the environment have been the sword of Damocles for
scrapie control and eradication. Attempts to establish which physical and
chemical agents could be applied to inactivate or moderate scrapie infectivity
were initiated in the 1960s and 1970s,with the first study of this type focusing
on the effect of heat treatment in reducing prion infectivity (Hunter and
Millson 1964). Nowadays, most of the chemical procedures that aim to inactivate
the prion protein are based on the method developed by Kimberlin and
collaborators (1983). This procedure consists of treatment with 20,000 parts per
million free chlorine solution, for a minimum of one hour, of all surfaces that
need to be sterilised (in laboratories, lambing pens, slaughterhouses, and so
on). Despite this, veterinarians and farmers may still ask a range of questions,
such as ‘Is there an official procedure published somewhere?’ and ‘Is there an
international organisation which recommends and defines the exact method of
scrapie decontamination that must be applied?’
From a European perspective, it is difficult to find a treatment that could
be applied, especially in relation to the disinfection of surfaces in lambing
pens of affected flocks. A 999/2001 EU regulation on controlling spongiform
encephalopathies (European Parliament and Council 2001) did not specify a
particular decontamination measure to be used when an outbreak of scrapie is
diagnosed. There is only a brief recommendation in Annex VII concerning the
control and eradication of transmissible spongiform encephalopathies (TSE
s).
Chapter B of the regulation explains the measures that must be applied if
new caprine animals are to be introduced to a holding where a scrapie outbreak
has previously been diagnosed. In that case, the statement indicates that
caprine animals can be introduced ‘provided that a cleaning and disinfection of
all animal housing on the premises has been carried out following
destocking’.
Issues around cleaning and disinfection are common in prion prevention
recommendations, but relevant authorities, veterinarians and farmers may have
difficulties in finding the specific protocol which applies. The European Food
and Safety Authority (EFSA ) published a detailed report about the efficacy of
certain biocides, such as sodium hydroxide, sodium hypochlorite, guanidine and
even a formulation of copper or iron metal ions in combination with hydrogen
peroxide, against prions (EFSA 2009). The report was based on scientific
evidence (Fichet and others 2004, Lemmer and others 2004, Gao and others 2006,
Solassol and others 2006) but unfortunately the decontamination measures were
not assessed under outbreak conditions.
The EFSA Panel on Biological Hazards recently published its conclusions on
the scrapie situation in the EU after 10 years of monitoring and control of the
disease in sheep and goats (EFSA 2014), and one of the most interesting findings
was the Icelandic experience regarding the effect of disinfection in scrapie
control. The Icelandic plan consisted of: culling scrapie-affected sheep or the
whole flock in newly diagnosed outbreaks; deep cleaning and disinfection of
stables, sheds, barns and equipment with high pressure washing followed by
cleaning with 500 parts per million of hypochlorite; drying and treatment with
300 ppm of iodophor; and restocking was not permitted for at least two years.
Even when all of these measures were implemented, scrapie recurred on several
farms, indicating that the infectious agent survived for years in the
environment, even as many as 16 years after restocking (Georgsson and others
2006).
In the rest of the countries considered in the EFSA (2014) report,
recommendations for disinfection measures were not specifically defined at the
government level. In the report, the only recommendation that is made for sheep
is repopulation with sheep with scrapie-resistant genotypes. This reduces the
risk of scrapie recurrence but it is difficult to know its effect on the
infection.
Until the EFSA was established (in May 2003), scientific opinions about TSE
s were provided by the Scientific Steering Committee (SSC) of the EC, whose
advice regarding inactivation procedures focused on treating animal waste at
high temperatures (150°C for three hours) and high pressure alkaline hydrolysis
(SSC 2003). At the same time, the TSE Risk Management Subgroup of the Advisory
Committee on Dangerous Pathogens (ACDP) in the UK published guidance on safe
working and the prevention of TSE infection. Annex C of the ACDP report
established that sodium hypochlorite was considered to be effective, but only if
20,000 ppm of available chlorine was present for at least one hour, which has
practical limitations such as the release of chlorine gas, corrosion,
incompatibility with formaldehyde, alcohols and acids, rapid inactivation of its
active chemicals and the stability of dilutions (ACDP 2009).
In an international context, the World Organisation for Animal Health (OIE)
does not recommend a specific disinfection protocol for prion agents in its
Terrestrial Code or Manual. Chapter 4.13 of the Terrestrial Code, General
recommendations on disinfection and disinsection (OIE 2014), focuses on
foot-and-mouth disease virus, mycobacteria and Bacillus anthracis, but not on
prion disinfection. Nevertheless, the last update published by the OIE on bovine
spongiform encephalopathy (OIE 2012) indicates that few effective
decontamination techniques are available to inactivate the agent on surfaces,
and recommends the removal of all organic material and the use of sodium
hydroxide, or a sodium hypochlorite solution containing 2 per cent available
chlorine, for more than one hour at 20ºC.
The World Health Organization outlines guidelines for the control of TSE s,
and also emphasises the importance of mechanically cleaning surfaces before
disinfection with sodium hydroxide or sodium hypochlorite for one hour (WHO
1999).
Finally, the relevant agencies in both Canada and the USA suggest that the
best treatments for surfaces potentially contaminated with prions are sodium
hydroxide or sodium hypochlorite at 20,000 ppm. This is a 2 per cent solution,
while most commercial household bleaches contain 5.25 per cent sodium
hypochlorite. It is therefore recommended to dilute one part 5.25 per cent
bleach with 1.5 parts water (CDC 2009, Canadian Food Inspection Agency
2013).
So what should we do about disinfection against prions? First, it is
suggested that a single protocol be created by international authorities to
homogenise inactivation procedures and enable their application in all
scrapie-affected countries. Sodium hypochlorite with 20,000 ppm of available
chlorine seems to be the procedure used in most countries, as noted in a paper
summarised on p 99 of this issue of Veterinary Record (Hawkins and others 2015).
But are we totally sure of its effectiveness as a preventive measure in a
scrapie outbreak? Would an in-depth study of the recurrence of scrapie disease
be needed?
What we can conclude is that, if we want to fight prion diseases, and
specifically classical scrapie, we must focus on the accuracy of diagnosis,
monitoring and surveillance; appropriate animal identification and control of
movements; and, in the end, have homogeneous and suitable protocols to
decontaminate and disinfect lambing barns, sheds and equipment available to
veterinarians and farmers. Finally, further investigations into the resistance
of prion proteins in the diversity of environmental surfaces are required.
References
snip...
98 | Veterinary Record | January 24, 2015
Persistence of ovine scrapie infectivity in a farm environment following
cleaning and decontamination
Steve A. C. Hawkins, MIBiol, Pathology Department1, Hugh A. Simmons, BVSc
MRCVS, MBA, MA Animal Services Unit1, Kevin C. Gough, BSc, PhD2 and Ben C.
Maddison, BSc, PhD3 + Author Affiliations
1Animal and Plant Health Agency, Woodham Lane, New Haw, Addlestone, Surrey
KT15 3NB, UK 2School of Veterinary Medicine and Science, The University of
Nottingham, Sutton Bonington, Loughborough, Leicestershire LE12 5RD, UK 3ADAS
UK, School of Veterinary Medicine and Science, The University of Nottingham,
Sutton Bonington, Loughborough, Leicestershire LE12 5RD, UK E-mail for
correspondence: ben.maddison@adas.co.uk Abstract Scrapie of sheep/goats and
chronic wasting disease of deer/elk are contagious prion diseases where
environmental reservoirs are directly implicated in the transmission of disease.
In this study, the effectiveness of recommended scrapie farm decontamination
regimens was evaluated by a sheep bioassay using buildings naturally
contaminated with scrapie. Pens within a farm building were treated with either
20,000 parts per million free chorine solution for one hour or were treated with
the same but were followed by painting and full re-galvanisation or replacement
of metalwork within the pen. Scrapie susceptible lambs of the PRNP genotype
VRQ/VRQ were reared within these pens and their scrapie status was monitored by
recto-anal mucosa-associated lymphoid tissue. All animals became infected over
an 18-month period, even in the pen that had been subject to the most stringent
decontamination process. These data suggest that recommended current guidelines
for the decontamination of farm buildings following outbreaks of scrapie do
little to reduce the titre of infectious scrapie material and that environmental
recontamination could also be an issue associated with these premises.
SNIP...
Discussion
Thorough pressure washing of a pen had no effect on the amount of
bioavailable scrapie infectivity (pen B). The routine removal of prions from
surfaces within a laboratory setting is treatment for a minimum of one hour with
20,000 ppm free chlorine, a method originally based on the use of brain
macerates from infected rodents to evaluate the effectiveness of decontamination
(Kimberlin and others 1983). Further studies have also investigated the
effectiveness of hypochlorite disinfection of metal surfaces to simulate the
decontamination of surgical devices within a hospital setting. Such treatments
with hypochlorite solution were able to reduce infectivity by 5.5 logs to lower
than the sensitivity of the bioassay used (Lemmer and others 2004). Analogous
treatment of the pen surfaces did not effectively remove the levels of scrapie
infectivity over that of the control pens, indicating that this method of
decontamination is not effective within a farm setting. This may be due to the
high level of biological matrix that is present upon surfaces within the farm
environment, which may reduce the amount of free chlorine available to
inactivate any infectious prion. Remarkably 1/5 sheep introduced into pen D had
also became scrapie positive within nine months, with all animals in this pen
being RAMALT positive by 18 months of age. Pen D was no further away from the
control pen (pen A) than any of the other pens within this barn. Localised hot
spots of infectivity may be present within scrapie-contaminated environments,
but it is unlikely that pen D area had an amount of scrapie contamination that
was significantly different than the other areas within this building.
Similarly, there were no differences in how the biosecurity of pen D was
maintained, or how this pen was ventilated compared with the other pens. This
observation, perhaps, indicates the slower kinetics of disease uptake within
this pen and is consistent with a more thorough prion removal and
recontamination. These observations may also account for the presence of
inadvertent scrapie cases within other studies, where despite stringent
biosecurity, control animals have become scrapie positive during challenge
studies using barns that also housed scrapie-affected animals (Ryder and others
2009). The bioassay data indicate that the exposure of the sheep to a farm
environment after decontamination efforts thought to be effective in removing
scrapie is sufficient for the animals to become infected with scrapie. The main
exposure routes within this scenario are likely to be via the oral route, during
feeding and drinking, and respiratory and conjunctival routes. It has been
demonstrated that scrapie infectivity can be efficiently transmitted via the
nasal route in sheep (Hamir and others 2008), as is the case for CWD in both
murine models and in white-tailed deer (Denkers and others 2010, 2013).
Recently, it has also been demonstrated that CWD prions presented as dust when
bound to the soil mineral montmorillonite can be infectious via the nasal route
(Nichols and others 2013). When considering pens C and D, the actual source of
the infectious agent in the pens is not known, it is possible that biologically
relevant levels of prion survive on surfaces during the decontamination regimen
(pen C). With the use of galvanising and painting (pen D) covering and sealing
the surface of the pen, it is possible that scrapie material recontaminated the
pens by the movement of infectious prions contained within dusts originating
from other parts of the barn that were not decontaminated or from other areas of
the farm.
Given that scrapie prions are widespread on the surfaces of affected farms
(Maddison and others 2010a), irrespective of the source of the infectious prions
in the pens, this study clearly highlights the difficulties that are faced with
the effective removal of environmentally associated scrapie infectivity. This is
likely to be paralleled in CWD which shows strong similarities to scrapie in
terms of both the dissemination of prions into the environment and the facile
mode of disease transmission. These data further contribute to the understanding
that prion diseases can be highly transmissible between susceptible individuals
not just by direct contact but through highly stable environmental reservoirs
that are refractory to decontamination.
The presence of these environmentally associated prions in farm buildings
make the control of these diseases a considerable challenge, especially in
animal species such as goats where there is lack of genetic resistance to
scrapie and, therefore, no scope to re-stock farms with animals that are
resistant to scrapie.
Scrapie Sheep Goats Transmissible spongiform encephalopathies (TSE)
Accepted October 12, 2014. Published Online First 31 October 2014
Monday, November 3, 2014
Persistence of ovine scrapie infectivity in a farm environment following
cleaning and decontamination
PPo3-22:
Detection of Environmentally Associated PrPSc on a Farm with Endemic
Scrapie
Ben C. Maddison,1 Claire A. Baker,1 Helen C. Rees,1 Linda A. Terry,2 Leigh
Thorne,2 Susan J. Belworthy2 and Kevin C. Gough3 1ADAS-UK LTD; Department of
Biology; University of Leicester; Leicester, UK; 2Veterinary Laboratories
Agency; Surry, KT UK; 3Department of Veterinary Medicine and Science; University
of Nottingham; Sutton Bonington, Loughborough UK
Key words: scrapie, evironmental persistence, sPMCA
Ovine scrapie shows considerable horizontal transmission, yet the routes of
transmission and specifically the role of fomites in transmission remain poorly
defined. Here we present biochemical data demonstrating that on a
scrapie-affected sheep farm, scrapie prion contamination is widespread. It was
anticipated at the outset that if prions contaminate the environment that they
would be there at extremely low levels, as such the most sensitive method
available for the detection of PrPSc, serial Protein Misfolding Cyclic
Amplification (sPMCA), was used in this study. We investigated the distribution
of environmental scrapie prions by applying ovine sPMCA to samples taken from a
range of surfaces that were accessible to animals and could be collected by use
of a wetted foam swab. Prion was amplified by sPMCA from a number of these
environmental swab samples including those taken from metal, plastic and wooden
surfaces, both in the indoor and outdoor environment. At the time of sampling
there had been no sheep contact with these areas for at least 20 days prior to
sampling indicating that prions persist for at least this duration in the
environment. These data implicate inanimate objects as environmental reservoirs
of prion infectivity which are likely to contribute to disease transmission.
Friday, May 22, 2015
Chronic Wasting Disease and Program Updates - 2014 NEUSAHA Annual Meeting
12-14 May 2014
U.S. Attorneys » Eastern District of Missouri » News Justice News
Department of Justice U.S. Attorney’s Office Eastern District of Missouri
--------------------------------------------------------------------------------
FOR IMMEDIATE RELEASE
Wednesday, June 10, 2015
Missouri Resident Charged with Federal Lacey Act Violations St Louis, MO –
CHARLES "SAM" JAMES, Columbia, Missouri, was charged in a one-count federal
indictment for violations of the Lacey Act for engaging in conduct that involved
the sale of white-tailed deer transported in violation of Missouri and Florida
law.
According to the indictment, in October 2013, Charles “Sam” James, co-owner
of Timber Hollow Whitetails, transported eleven live white-tailed deer in
interstate commerce in violation of state and federal laws from Missouri to a
white-tailed deer farm in Florida. The transportation of these animals took
place after a Florida state law took effect banning the importation of captive
white-tailed deer. The defendant allegedly transported the deer from Timber
Hollow Whitetails near Mexico, Missouri, in a rented utility box trailer, to a
deer farm near Laurel Hills, Florida.
Federal law makes it unlawful to transport live white-tailed deer out of
the State of Missouri or into the State of Florida without proper documentation
of the animals and without required animal health records. These health records
include certifying that captive-bred animals are free from diseases like chronic
wasting disease, tuberculosis and brucellosis.
Chronic wasting disease is the chief threat to wild deer and elk
populations in North America. The disease, which ultimately ends in the death of
infected animals, is a transmissible neurological disease that produces small
lesions in the brain of deer and elk and is characterized by loss of body
condition and behavioral abnormalities.
If convicted, this charge carries a maximum penalty of five years in
prison, a $250,000 fine or both. In determining the actual sentences, a judge is
required to consider the U.S. Sentencing Guidelines, which provide recommended
sentencing ranges.
This case was investigated by agents from the U.S. Fish and Wildlife
Service, the Missouri Department of Conservation and the Florida Fish and
Wildlife Conservation Commission. Assistant United States Attorney Dianna
Collins is handling the case for the U.S. Attorney’s Office.
As is always the case, charges set forth in an indictment are merely
accusations and do not constitute proof of guilt. Every defendant is presumed to
be innocent unless and until proven guilty.
USAO - Missouri, Eastern District Updated June 10, 2015
Sam James, president of the Missouri Deer Association, said their
association is determined to see this process through to the end. “Our state
legislators already passed the bills overwhelmingly because they get it. They
looked at the science and facts and compared them with the negative media hype
from the conservation special interest groups. It didn’t add up and we are
grateful for their courage to stand for what’s right.”
The Missouri Department of Conservation has publically stated that the deer
farmers are a probable catalyst for the spread of Chronic Wasting Disease (CWD)
and therefore opposed the passage of the bills.
Tuesday, June 16, 2015
Missouri MDC changes deer hunting regs to help slow CWD
Thursday, May 15, 2014
Missouri Stripping MDC regulatory authority of deer farms SB 506 HOW THEY
VOTED Singeltary letter to Governor Nixon
MDC reports two new cases of CWD found in Adair and Macon counties
Published on: Jan. 26, 2015
Posted by Joe Jerek
JEFFERSON CITY, Mo. -- The Missouri Department of Conservation (MDC)
reports that two new cases of chronic wasting disease (CWD) have recently been
found in north-central Missouri. One was found in an adult buck harvested by a
hunter in Macon County and the other in an adult doe harvested by a hunter in
Adair County. These two new cases bring the total of Missouri free-ranging deer
that have tested positive for CWD to five for this hunting season and 15
overall. The total cases of CWD in Missouri captive and free-ranging deer now
stands at 26.
CWD was first discovered in Missouri in 2010 at a private hunting preserve
in Linn County. All cases of CWD in Missouri have been limited to Macon, Linn,
and Adair counties, which are part of MDC's six-county CWD Containment Zone.
Additional counties included in the zone are Chariton, Randolph, and Sullivan.
Monday, January 26, 2015
Missouri MDC reports two new cases of CWD found in Adair and Macon counties
Friday, September 20, 2013
Missouri State records show gaps in oversight of captive deer farms,
ranches
a few escapees off the top of my head ;
Tuesday, November 27, 2012
Pennsylvania ‘Pink 23’ Adams County exposed CWD Escaped Deer shot, but
where are the other escapees ?
Saturday, June 29, 2013
PENNSYLVANIA CAPTIVE CWD INDEX HERD MATE YELLOW *47 STILL RUNNING LOOSE IN
INDIANA, YELLOW NUMBER 2 STILL MISSING, AND OTHERS ON THE RUN STILL IN LOUISIANA
Tuesday, June 11, 2013
CWD GONE WILD, More cervid escapees from more shooting pens on the loose in
Pennsylvania
Wisconsin : 436 Deer Have Escaped From Farms to Wild
Date: March 18, 2003 Source: Milwaukee Journal Sentinel
Contacts: LEE BERGQUIST lbergquist@journalsentinel.com
State finds violations, lax record keeping at many sites, report says A
state inspection of private deer farms, prompted by the discovery of chronic
wasting disease, found that 436 white-tailed deer escaped into the wild,
officials said Tuesday
The Department of Natural Resources found that captive deer have escaped
from one-third of the state's 550 deer farms over the lifetime of the
operations. The agency also uncovered hundreds of violations and has sought a
total of 60 citations or charges against deer farm operators.
Hundreds of deer escape
The DNR found a total of 671 deer that escaped farms - 436 of which were
never found - because of storm-damaged fences, gates being left open or the
animals jumping over or through fences.
In one example in Kewaunee County, a deer farmer's fence was knocked down
in a summer storm. Ten deer escaped, and the farmer told the DNR he had no
intention of trying to reclaim them. The DNR found five of the deer, killed them
and cited the farmer for violation of a regulation related to fencing.
Another deer farmer near Mishicot, in Manitowoc County, released all nine
of his whitetails last summer after he believed the discovery of chronic wasting
disease was going to drive down the market for captive deer.
The DNR found 24 instances of unlicensed deer farms and issued 19
citations.
Game Farms Inspected
A summary of the findings of the Department of Natural Resources'
inspection of 550 private white-tailed deer farms in the state: The deer farms
contained at least 16,070 deer, but the DNR believes there are more deer in
captivity than that because large deer farms are unable to accurately count
their deer. 671 deer had escaped from game farms, including 436 that were never
found.
24 farmers were unlicensed. One had been operating illegally since 1999
after he was denied a license because his deer fence did not meet minimum
specifications.
Records maintained by operators ranged from "meticulous documentation to
relying on memory." At least 227 farms conducted various portions of their deer
farm business with cash. Over the last three years, 1,222 deer died on farms for
various reasons. Disease testing was not performed nor required on the majority
of deer. Farmers reported doing business with people in 22 other states and one
Canadian province. ..
Earl Ray Tomblin, Governor Frank Jezioro, Director
News Release: November 4, 2011
Facebook: WV Commerce - State Parks
Hoy Murphy, Public Information Officer (304) 957-9365 hoy.r.murphy@wv.gov
Contact: Curtis Taylor, Wildlife Resources Section Chief 304-558-2771
DNR.Wildlife@wv.gov
Elk escape from captive cervid facility in Pennsylvania near West Virginia
border
SOUTH CHARLESTON, W.Va. – The West Virginia Division of Natural Resources
(WVDNR) has confirmed with officials from the Pennsylvania Department of
Agriculture (PDA) that at least two elk, including one adult bull and one cow,
have escaped from a captive cervid facility (deer and elk farms) in Greene
County, Pa. Greene County shares a common border with Marshall, Wetzel and
Monongalia counties in West Virginia. The elk escaped from a captive cervid
facility located approximately three miles from the West Virginia-Pennsylvania
border.
The PDA regulates captive cervid facilities in Pennsylvania. A
representative of the agency was unaware if the recent escaped elk were tagged.
The WVDNR regulates captive cervid facilities in West Virginia. In West
Virginia, all captive cervids in breeding facilities must be ear-tagged, and
there are currently no reported elk escapes from any facility in West Virginia.
A bull elk has been seen recently in Wetzel County, W.Va., according to
WVDNR officials. There have been no reports of cow elk sightings in either
Wetzel County, W.Va., or Greene County, Pa. No free-ranging wild elk live within
150 miles of Wetzel County. The elk sighted in Wetzel County is likely the
escaped animal from the captive facility in Pennsylvania.
Friday, September 28, 2012
Stray elk renews concerns about deer farm security Minnesota
Monday, June 11, 2012
*** OHIO Captive deer escapees and non-reporting ***
Thursday, October 23, 2014
FIRST CASE OF CHRONIC WASTING DISEASE CONFIRMED IN OHIO ON PRIVATE PRESERVE
Thursday, April 02, 2015
OHIO CONFIRMS SECOND POSTIVE CHRONIC WASTING DISEASE CWD on Yoder's
properties near Millersburg
Wednesday, February 11, 2015
World Class Whitetails quarantined CWD deer Daniel M. Yoder charged with
two counts of tampering with evidence
Friday, April 04, 2014
*** Wisconsin State officials kept silent on CWD discovery at game farm ***
Tuesday, October 07, 2014
*** Wisconsin white-tailed deer tested positive for CWD on a Richland
County breeding farm, and a case of CWD has been discovered on a Marathon County
hunting preserve
Wednesday, March 04, 2015
Disease sampling results provide current snapshot of CWD in Wisconsin
finding 324 positive detections statewide in 2014
Friday, July 17, 2015
*** TPW Commission Holds Special Meeting on Chronic Wasting Disease
Wednesday, July 01, 2015
TEXAS Chronic Wasting Disease Detected in Medina County Captive Deer
Thursday, July 09, 2015
TEXAS Chronic Wasting Disease (CWD) Herd Plan for Trace-Forward Exposed
Herd with Testing of Exposed Animals
Tuesday, July 14, 2015
Texas Parks and Wildlife Commission Special Meeting Thursday on Chronic
Wasting Disease CWD
Rare report of deer disease in Texas causes stir
Houston Chronicle
Rare report of deer disease in Texas causes stir, especially since it’s the
8 case of CWD documented in Texas, and the first case of CWD in Captive deer.
here is how I would have titled this article, and why.
Shannon Tompkins Finally Breaks Silence on Texas First Captive CWD Case and
Starts Off Spreading False Information About Risk Factors. ...
Thursday, July 16, 2015
Wednesday, March 18, 2015
Chronic Wasting Disease CWD Confirmed Texas Trans Pecos March 18,
2015
Wednesday, March 25, 2015
Chronic Wasting Disease CWD Cases Confirmed In New Mexico 2013 and 2014
UPDATE 2015
Thursday, May 02, 2013
*** Chronic Wasting Disease (CWD) Texas Important Update on OBEX ONLY
TEXTING
Monday, February 11, 2013
TEXAS CHRONIC WASTING DISEASE CWD Four New Positives Found in Trans Pecos
Tuesday, July 10, 2012
Chronic Wasting Disease Detected in Far West Texas
Monday, March 26, 2012
Texas Prepares for Chronic Wasting Disease CWD Possibility in Far West
Texas
***for anyone interested, here is some history of CWD along the Texas, New
Mexico border, and my attempt to keep up with it...terry
snip...
see history CWD Texas, New Mexico Border ;
Monday, March 26, 2012
3 CASES OF CWD FOUND NEW MEXICO MULE DEER SEVERAL MILES FROM TEXAS BORDER
Sunday, October 04, 2009
CWD NEW MEXICO SPREADING SOUTH TO TEXAS 2009 2009 Summary of Chronic
Wasting Disease in New Mexico New Mexico Department of Game and Fish
Friday, May 22, 2015
*** Chronic Wasting Disease and Program Updates - 2014 NEUSAHA Annual
Meeting 12-14 May 2014
Sunday, July 12, 2015
*** Insights into CWD and BSE species barriers using real-time conversion
Wednesday, July 15, 2015
Kansas Ten Deer Test Positive for CWD in 2014-2015 7-16-15 News
Wednesday, July 01, 2015
DRAFT Virginia Deer Management Plan 2015-2024 (bans urine scents do to CWD
2015)
Tuesday, July 14, 2015
*** TWO Escaped Captive Deer on the loose in Eau Claire County Wisconsin
CWD postive farm Yellow ear tag
Thursday, June 25, 2015
Wisconsin CWD-positive white-tailed deer found on Eau Claire County farm
TEXAS MAD COW TRACE BACK EFFORTS ???
TEXAS MAD COW
THEY DID FINALLY TEST AFTER SITTING 7+ MONTHS ON A SHELF WHILE GW BORE THE
BSE MRR POLICY, i.e. legal trading of all strains of TSE. now understand, i
confirmed this case 7 months earlier to the TAHC, and then, only after i
contacted the Honorable Phyllis Fong and after an act of Congress, this animal
was finally confirmed ;
During the course of the investigation, USDA removed and tested a total of
67 animals of interest from the farm where the index animal's herd originated.
All of these animals tested negative for BSE. 200 adult animals of interest were
determined to have left the index farm. Of these 200, APHIS officials determined
that 143 had gone to slaughter, two were found alive (one was determined not to
be of interest because of its age and the other tested negative), 34 are
presumed dead, one is known dead and 20 have been classified as untraceable. In
addition to the adult animals, APHIS was looking for two calves born to the
index animal. Due to record keeping and identification issues, APHIS had to
trace 213 calves. Of these 213 calves, 208 entered feeding and slaughter
channels, four are presumed to have entered feeding and slaughter channels and
one calf was untraceable.
Executive Summary In June 2005, an inconclusive bovine spongiform
encephalopathy (BSE) sample from November 2004, that had originally been
classified as negative on the immunohistochemistry test, was confirmed positive
on SAF immunoblot (Western blot). The U.S. Department of Agriculture (USDA)
identified the herd of origin for the index cow in Texas; that identification
was confirmed by DNA analysis. USDA, in close cooperation with the Texas Animal
Health Commission (TAHC), established an incident command post (ICP) and began
response activities according to USDA’s BSE Response Plan of September 2004.
Response personnel removed at-risk cattle and cattle of interest (COI) from the
index herd, euthanized them, and tested them for BSE; all were negative. USDA
and the State extensively traced all at-risk cattle and COI that left the index
herd. The majority of these animals entered rendering and/or slaughter channels
well before the investigation began. USDA’s response to the Texas finding was
thorough and effective.
snip...
Trace Herd 3
The owner of Trace Herd 3 was identified as possibly having received an
animal of interest. The herd was placed under hold order on 7/27/05. The herd
inventory was conducted on 7/28/05. The animal of interest was not present
within the herd, and the hold order was released on 7/28/05. The person who
thought he sold the animal to the owner of Trace Herd 3 had no records and could
not remember who else he might have sold the cow to. Additionally, a search of
GDB for all cattle sold through the markets by that individual did not result in
a match to the animal of interest.
*** The animal of interest traced to this herd was classified as
untraceable because all leads were exhausted.
Trace Herd 4
The owner of Trace Herd 4 was identified as having received one of the COI
through an order buyer. Trace Herd 4 was placed under hold order on 7/29/05. A
complete herd inventory was conducted on 8/22/05 and 8/23/05. There were 233
head of cattle that were examined individually by both State and Federal
personnel for all man-made identification and brands. The animal of interest was
not present within the herd. Several animals were reported to have died in the
herd sometime after they arrived on the premises in April 2005. A final search
of GDB records yielded no further results on the eartag of interest at either
subsequent market sale or slaughter.
***With all leads having been exhausted, this animal of interest has been
classified as untraceable. The hold order on Trace Herd 4 was released on
8/23/05.
Trace Herd 5
The owner of Trace Herd 5 was identified as having received two COI and was
placed under hold order on 8/1/05. Trace Herd 5 is made up of 67 head of cattle
in multiple pastures. During the course of the herd inventory, the owner located
records that indicated that one of the COI, a known birth cohort, had been sold
to Trace Herd 8 where she was subsequently found alive. Upon completion of the
herd inventory, the other animal of interest was not found within the herd.
***A GDB search of all recorded herd tests conducted on Trace Herd 5 and
all market sales by the owner failed to locate the identification tag of the
animal of interest and she was subsequently classified as untraceable due to all
leads having been exhausted. The hold order on Trace Herd 5 was released on
8/8/05.
Trace Herd 6
The owner of Trace Herd 6 was identified as possibly having received an
animal of interest and was placed under hold order on 8/1/05. This herd is made
up of 58 head of cattle on two pastures. A herd inventory was conducted and the
animal of interest was not present within the herd. The owner of Trace Herd 6
had very limited records and was unable to provide further information on where
the cow might have gone after he purchased her from the livestock market. A
search of GDB for all cattle sold through the markets by that individual did not
result in a match to the animal of interest. Additionally, many of the animals
presented for sale by the owner of the herd had been re-tagged at the market
effectually losing the traceability of the history of that animal prior to
re-tagging.
*** The animal of interest traced to this herd was classified as
untraceable due to all leads having been exhausted. The hold order on Trace Herd
6 was released on 8/3/05.
Trace Herd 7
The owner of Trace Herd 7 was identified as having received an animal of
interest and was placed under hold order on 8/1/05. Trace Herd 7 contains 487
head of cattle on multiple pastures in multiple parts of the State, including a
unit kept on an island. The island location is a particularly rough place to
keep cattle and the owner claimed to have lost 22 head on the island in 2004 due
to liver flukes. Upon completion of the herd inventory, the animal of interest
was not found present within Trace Herd 7. A GDB search of all recorded herd
tests conducted on Trace Herd 7 and all market sales by the owner failed to
locate the identification tag of the animal of interest.
*** The cow was subsequently classified as untraceable. It is quite
possible though that she may have died within the herd, especially if she
belonged to the island unit. The hold order on Trace Herd 7 was released on
8/8/05.
FDA has determined that each animal could have consumed, at most and in
total, five-and-one-half grams - approximately a quarter ounce -- of prohibited
material. These animals weigh approximately 600 pounds.
THE USDA JUNE 2004 ENHANCED BSE SURVEILLANCE PROGRAM WAS TERRIBLY FLAWED ;
CDC DR. PAUL BROWN TSE EXPERT COMMENTS 2006
In an article today for United Press International, science reporter Steve
Mitchell writes:
Analysis: What that mad cow means
By STEVE MITCHELL UPI Senior Medical Correspondent
WASHINGTON, March 15 (UPI) -- The U.S. Department of Agriculture was quick
to assure the public earlier this week that the third case of mad cow disease
did not pose a risk to them, but what federal officials have not acknowledged is
that this latest case indicates the deadly disease has been circulating in U.S.
herds for at least a decade.
The second case, which was detected last year in a Texas cow and which USDA
officials were reluctant to verify, was approximately 12 years old.
These two cases (the latest was detected in an Alabama cow) present a
picture of the disease having been here for 10 years or so, since it is thought
that cows usually contract the disease from contaminated feed they consume as
calves. The concern is that humans can contract a fatal, incurable,
brain-wasting illness from consuming beef products contaminated with the mad cow
pathogen.
"The fact the Texas cow showed up fairly clearly implied the existence of
other undetected cases," Dr. Paul Brown, former medical director of the National
Institutes of Health's Laboratory for Central Nervous System Studies and an
expert on mad cow-like diseases, told United Press International. "The question
was, 'How many?' and we still can't answer that."
Brown, who is preparing a scientific paper based on the latest two mad cow
cases to estimate the maximum number of infected cows that occurred in the
United States, said he has "absolutely no confidence in USDA tests before one
year ago" because of the agency's reluctance to retest the Texas cow that
initially tested positive.
USDA officials finally retested the cow and confirmed it was infected seven
months later, but only at the insistence of the agency's inspector
general.
"Everything they did on the Texas cow makes everything they did before 2005
suspect," Brown said.
Despite this, Brown said the U.S. prevalence of mad cow, formally known as
bovine spongiform encephalopathy, or BSE, did not significantly threaten human
or cattle health.
"Overall, my view is BSE is highly unlikely to pose any important risk
either in cattle feed or human feed," he said.
However, Jean Halloran of Consumers Union in Yonkers, N.Y., said consumers
should be troubled by the USDA's secrecy and its apparent plan to dramatically
cut back the number of mad cow tests it conducts.
"Consumers should be very concerned about how little we know about the
USDA's surveillance program and the failure of the USDA to reveal really
important details," Halloran told UPI. "Consumers have to be really concerned if
they're going to cut back the program," she added.
Last year the USDA tested more than 300,000 animals for the disease, but it
has proposed, even in light of a third case, scaling back the program to 40,000
tests annually.
"They seem to be, in terms of actions and policies, taking a lot more
seriously the concerns of the cattle industry than the concerns of consumers,"
Halloran said. "It's really hard to know what it takes to get this
administration to take action to protect the public."
The USDA has insisted that the safeguards of a ban on incorporating cow
tissue into cattle feed (which is thought to spread the disease) and removal of
the most infectious parts of cows, such as the brain and spinal cord, protect
consumers. But the agency glosses over the fact that both of these systems have
been revealed to be inadequately implemented.
The feed ban, which is enforced by the Food and Drug Administration, has
been criticized by the Government Accountability Office in two reports, the most
recent coming just last year. The GAO said the FDA's enforcement of the ban
continues to have weaknesses that "undermine the nation's firewall against
BSE."
USDA documents released last year showed more than 1,000 violations of the
regulations requiring the removal of brains and spinal cords in at least 35
states, Puerto Rico and the Virgin Islands, with some plants being cited
repeatedly for infractions. In addition, a violation of similar regulations that
apply to beef exported to Japan is the reason why Japan closed its borders to
U.S. beef in January six weeks after reopening them.
Other experts also question the adequacy of the USDA's surveillance system.
The USDA insists the prevalence of mad cow disease is low, but the agency has
provided few details of its surveillance program, making it difficult for
outside experts to know if the agency's monitoring plan is sufficient.
"It's impossible to judge the adequacy of the surveillance system without
having a breakdown of the tested population by age and risk status," Elizabeth
Mumford, a veterinarian and BSE expert at Safe Food Solutions in Bern,
Switzerland, a company that provides advice on reducing mad cow risk to industry
and governments, told UPI.
"Everybody would be happier and more confident and in a sense it might be
able to go away a little bit for (the USDA) if they would just publish a
breakdown on the tests," Mumford added.
UPI requested detailed records about animals tested under the USDA's
surveillance plan via the Freedom of Information Act in May 2004 but nearly two
years later has not received any corresponding documents from the agency,
despite a federal law requiring agencies to comply within 30 days. This leaves
open the question of whether the USDA is withholding the information, does not
have the information or is so haphazardly organized that it cannot locate
it.
Mumford said the prevalence of the disease in U.S. herds is probably quite
low, but there have probably been other cases that have so far gone undetected.
"They're only finding a very small fraction of that low prevalence," she
said.
Mumford expressed surprise at the lack of concern about the deadly disease
from American consumers. "I would expect the U.S. public to be more concerned,"
she said.
Markus Moser, a molecular biologist and chief executive officer of
Prionics, a Swiss firm that manufactures BSE test kits, told UPI one concern is
that if people are infected, the mad cow pathogen could become "humanized" or
more easily transmitted from person to person.
"Transmission would be much easier, through all kinds of medical
procedures" and even through the blood supply, Moser said.
© Copyright 2006 United Press International, Inc. All Rights Reserved
CDC - Bovine Spongiform Encephalopathy and Variant Creutzfeldt ... Dr. Paul
Brown is Senior Research Scientist in the Laboratory of Central Nervous System
... Address for correspondence: Paul Brown, Building 36, Room 4A-05, ...
PAUL BROWN COMMENT TO ME ON THIS ISSUE
Tuesday, September 12, 2006 11:10 AM
"Actually, Terry, I have been critical of the USDA handling of the mad cow
issue for some years, and with Linda Detwiler and others sent lengthy detailed
critiques and recommendations to both the USDA and the Canadian Food Agency."
........TSS
OR, what the Honorable Phyllis Fong of the OIG found ;
Audit Report Animal and Plant Health Inspection Service Bovine Spongiform
Encephalopathy (BSE) Surveillance Program  Phase II and Food Safety and
Inspection Service
Controls Over BSE Sampling, Specified Risk Materials, and Advanced Meat
Recovery Products - Phase III
Report No. 50601-10-KC January 2006
Finding 2 Inherent Challenges in Identifying and Testing High-Risk Cattle
Still Remain
Subject: USDA OIG SEMIANNUAL REPORT TO CONGRESS FY 2007 1st Half (bogus BSE
sampling FROM HEALTHY USDA CATTLE)
Date: June 21, 2007 at 2:49 pm PST
Owner and Corporation Plead Guilty to Defrauding Bovine Spongiform
Encephalopathy (BSE) Surveillance Program
An Arizona meat processing company and its owner pled guilty in February
2007 to charges of theft of Government funds, mail fraud, and wire fraud. The
owner and his company defrauded the BSE Surveillance Program when they falsified
BSE Surveillance Data Collection Forms and then submitted payment requests to
USDA for the services. In addition to the targeted sample population (those
cattle that were more than 30 months old or had other risk factors for BSE), the
owner submitted to USDA, or caused to be submitted, BSE obex (brain stem)
samples from healthy USDA-inspected cattle. As a result, the owner fraudulently
received approximately $390,000. Sentencing is scheduled for May 2007.
snip...
Topics that will be covered in ongoing or planned reviews under Goal 1
include:
soundness of BSE maintenance sampling (APHIS),
implementation of Performance-Based Inspection System enhancements for
specified risk material (SRM) violations and improved inspection controls over
SRMs (FSIS and APHIS),
snip...
The findings and recommendations from these efforts will be covered in
future semiannual reports as the relevant audits and investigations are
completed.
4 USDA OIG SEMIANNUAL REPORT TO CONGRESS FY 2007 1st Half
*** We describe the transmission of spongiform encephalopathy in a
non-human primate inoculated 10 years earlier with a strain of sheep c-scrapie.
Because of this extended incubation period in a facility in which other prion
diseases are under study, we are obliged to consider two alternative
possibilities that might explain its occurrence. We first considered the
possibility of a sporadic origin (like CJD in humans). Such an event is
extremely improbable because the inoculated animal was 14 years old when the
clinical signs appeared, i.e. about 40% through the expected natural lifetime of
this species, compared to a peak age incidence of 60–65 years in human sporadic
CJD, or about 80% through their expected lifetimes.
***Moreover, sporadic disease has never been observed in breeding colonies
or primate research laboratories, most notably among hundreds of animals over
several decades of study at the National Institutes of Health25, and in nearly
twenty older animals continuously housed in our own facility.***
>>> Moreover, sporadic disease has never been observed in breeding
colonies or primate research laboratories, most notably among hundreds of
animals over several decades of study at the National Institutes of Health25,
and in nearly twenty older animals continuously housed in our own facility.
<<<
Transmission of scrapie prions to primate after an extended silent
incubation period
Emmanuel E. Comoy1 , Jacqueline Mikol1 , Sophie Luccantoni-Freire1 ,
Evelyne Correia1 , Nathalie Lescoutra-Etchegaray1 , Valérie Durand1 , Capucine
Dehen1 , Olivier Andreoletti2 , Cristina Casalone3 , Juergen A. Richt4 n1 ,
Justin J. Greenlee4 , Thierry Baron5 , Sylvie L. Benestad6 , Paul Brown1 […]
& Jean-Philippe Deslys1 - Show fewer authors Scientific Reports 5, Article
number: 11573 (2015) doi:10.1038/srep11573 Download Citation
Epidemiology | Neurological manifestations | Prion diseases Received: 16
February 2015 Accepted: 28 May 2015 Published online: 30 June 2015 ABSTRACT
Classical bovine spongiform encephalopathy (c-BSE) is the only animal prion
disease reputed to be zoonotic, causing variant Creutzfeldt-Jakob disease (vCJD)
in humans and having guided protective measures for animal and human health
against animal prion diseases. Recently, partial transmissions to humanized mice
showed that the zoonotic potential of scrapie might be similar to c-BSE. We here
report the direct transmission of a natural classical scrapie isolate to
cynomolgus macaque, a highly relevant model for human prion diseases, after a
10-year silent incubation period, with features similar to those reported for
human cases of sporadic CJD. Scrapie is thus actually transmissible to primates
with incubation periods compatible with their life expectancy, although fourfold
longer than BSE. Long-term experimental transmission studies are necessary to
better assess the zoonotic potential of other prion diseases with high
prevalence, notably Chronic Wasting Disease of deer and elk and atypical/Nor98
scrapie.
snip...
Discussion
We describe the transmission of spongiform encephalopathy in a non-human
primate inoculated 10 years earlier with a strain of sheep c-scrapie. Because of
this extended incubation period in a facility in which other prion diseases are
under study, we are obliged to consider two alternative possibilities that might
explain its occurrence. We first considered the possibility of a sporadic origin
(like CJD in humans). Such an event is extremely improbable because the
inoculated animal was 14 years old when the clinical signs appeared, i.e. about
40% through the expected natural lifetime of this species, compared to a peak
age incidence of 60–65 years in human sporadic CJD, or about 80% through their
expected lifetimes. Moreover, sporadic disease has never been observed in
breeding colonies or primate research laboratories, most notably among hundreds
of animals over several decades of study at the National Institutes of Health25,
and in nearly twenty older animals continuously housed in our own
facility.
The second possibility is a laboratory cross-contamination. Three facts
make this possibility equally unlikely. First, handling of specimens in our
laboratory is performed with fastidious attention to the avoidance of any such
cross-contamination. Second, no laboratory cross-contamination has ever been
documented in other primate laboratories, including the NIH, even between
infected and uninfected animals housed in the same or adjacent cages with daily
intimate contact (P. Brown, personal communication). Third, the cerebral lesion
profile is different from all the other prion diseases we have studied in this
model19, with a correlation between cerebellar lesions (massive spongiform
change of Purkinje cells, intense PrPres staining and reactive gliosis26) and
ataxia. The iron deposits present in the globus pallidus are a non specific
finding that have been reported previously in neurodegenerative diseases and
aging27. Conversely, the thalamic lesion was reminiscent of a metabolic disease
due to thiamine deficiency28 but blood thiamine levels were within normal limits
(data not shown). The preferential distribution of spongiform change in cortex
associated with a limited distribution in the brainstem is reminiscent of the
lesion profile in MM2c and VV1 sCJD patients29, but interspecies comparison of
lesion profiles should be interpreted with caution. It is of note that the same
classical scrapie isolate induced TSE in C57Bl/6 mice with similar incubation
periods and lesional profiles as a sample derived from a MM1 sCJD
patient30.
We are therefore confident that the illness in this cynomolgus macaque
represents a true transmission of a sheep c-scrapie isolate directly to an
old-world monkey, which taxonomically resides in the primate subdivision
(parvorder of catarrhini) that includes humans. With an homology of its PrP
protein with humans of 96.4%31, cynomolgus macaque constitutes a highly relevant
model for assessing zoonotic risk of prion diseases. Since our initial aim was
to show the absence of transmission of scrapie to macaques in the worst-case
scenario, we obtained materials from a flock of naturally-infected sheep,
affecting animals with different genotypes32. This c-scrapie isolate exhibited
complete transmission in ARQ/ARQ sheep (332 ± 56 days) and Tg338 transgenic mice
expressing ovine VRQ/VRQ prion protein (220 ± 5 days) (O. Andreoletti, personal
communication). From the standpoint of zoonotic risk, it is important to note
that sheep with c-scrapie (including the isolate used in our study) have
demonstrable infectivity throughout their lymphoreticular system early in the
incubation period of the disease (3 months-old for all the lymphoid organs, and
as early as 2 months-old in gut-associated lymph nodes)33. In addition, scrapie
infectivity has been identified in blood34, milk35 and skeletal muscle36 from
asymptomatic but scrapie infected small ruminants which implies a potential
dietary exposure for consumers.
Two earlier studies have reported the occurrence of clinical TSE in
cynomolgus macaques after exposures to scrapie isolates. In the first study, the
“Compton” scrapie isolate (derived from an English sheep) and serially
propagated for 9 passages in goats did not transmit TSE in cynomolgus macaque,
rhesus macaque or chimpanzee within 7 years following intracerebral challenge1;
conversely, after 8 supplementary passages in conventional mice, this “Compton”
isolate induced TSE in a cynomolgus macaque 5 years after intracerebral
challenge, but rhesus macaques and chimpanzee remained asymptomatic 8.5 years
post-exposure8. However, multiple successive passages that are classically used
to select laboratory-adapted prion strains can significantly modify the initial
properties of a scrapie isolate, thus questioning the relevance of zoonotic
potential for the initial sheep-derived isolate. The same isolate had also
induced disease into squirrel monkeys (new-world monkey)9. A second historical
observation reported that a cynomolgus macaque developed TSE 6 years
post-inoculation with brain homogenate from a scrapie-infected Suffolk ewe
(derived from USA), whereas a rhesus macaque and a chimpanzee exposed to the
same inoculum remained healthy 9 years post-exposure1. This inoculum also
induced TSE in squirrel monkeys after 4 passages in mice. Other scrapie
transmission attempts in macaque failed but had more shorter periods of
observation in comparison to the current study. Further, it is possible that
there are differences in the zoonotic potential of different scrapie
strains.
The most striking observation in our study is the extended incubation
period of scrapie in the macaque model, which has several implications. Firstly,
our observations constitute experimental evidence in favor of the zoonotic
potential of c-scrapie, at least for this isolate that has been extensively
studied32,33,34,35,36. The cross-species zoonotic ability of this isolate should
be confirmed by performing duplicate intracerebral exposures and assessing the
transmissibility by the oral route (a successful transmission of prion strains
through the intracerebral route may not necessarily indicate the potential for
oral transmission37). However, such confirmatory experiments may require more
than one decade, which is hardly compatible with current general management and
support of scientific projects; thus this study should be rather considered as a
case report.
Secondly, transmission of c-BSE to primates occurred within 8 years post
exposure for the lowest doses able to transmit the disease (the survival period
after inoculation is inversely proportional to the initial amount of infectious
inoculum). The occurrence of scrapie 10 years after exposure to a high dose (25
mg) of scrapie-infected sheep brain suggests that the macaque has a higher
species barrier for sheep c-scrapie than c-BSE, although it is notable that
previous studies based on in vitro conversion of PrP suggested that BSE and
scrapie prions would have a similar conversion potential for human PrP38.
Thirdly, prion diseases typically have longer incubation periods after oral
exposure than after intracerebral inoculations: since humans can develop Kuru 47
years after oral exposure39, an incubation time of several decades after oral
exposure to scrapie would therefore be expected, leading the disease to occur in
older adults, i.e. the peak age for cases considered to be sporadic disease, and
making a distinction between scrapie-associated and truly sporadic disease
extremely difficult to appreciate.
Fourthly, epidemiologic evidence is necessary to confirm the zoonotic
potential of an animal disease suggested by experimental studies. A relatively
short incubation period and a peculiar epidemiological situation (e.g., all the
first vCJD cases occurring in the country with the most important ongoing c-BSE
epizootic) led to a high degree of suspicion that c-BSE was the cause of vCJD.
Sporadic CJD are considered spontaneous diseases with an almost stable and
constant worldwide prevalence (0.5–2 cases per million inhabitants per year),
and previous epidemiological studies were unable to draw a link between sCJD and
classical scrapie6,7,40,41, even though external causes were hypothesized to
explain the occurrence of some sCJD clusters42,43,44. However, extended
incubation periods exceeding several decades would impair the predictive values
of epidemiological surveillance for prion diseases, already weakened by a
limited prevalence of prion diseases and the multiplicity of isolates gathered
under the phenotypes of “scrapie” and “sporadic CJD”.
Fifthly, considering this 10 year-long incubation period, together with
both laboratory and epidemiological evidence of decade or longer intervals
between infection and clinical onset of disease, no premature conclusions should
be drawn from negative transmission studies in cynomolgus macaques with less
than a decade of observation, as in the aforementioned historical transmission
studies of scrapie to primates1,8,9. Our observations and those of others45,46
to date are unable to provide definitive evidence regarding the zoonotic
potential of CWD, atypical/Nor98 scrapie or H-type BSE. The extended incubation
period of the scrapie-affected macaque in the current study also underscores the
limitations of rodent models expressing human PrP for assessing the zoonotic
potential of some prion diseases since their lifespan remains limited to
approximately two years21,47,48. This point is illustrated by the fact that the
recently reported transmission of scrapie to humanized mice was not associated
with clinical signs for up to 750 days and occurred in an extreme minority of
mice with only a marginal increase in attack rate upon second passage13. The low
attack rate in these studies is certainly linked to the limited lifespan of mice
compared to the very long periods of observation necessary to demonstrate the
development of scrapie. Alternatively, one could estimate that a successful
second passage is the result of strain adaptation to the species barrier, thus
poorly relevant of the real zoonotic potential of the original scrapie isolate
of sheep origin49. The development of scrapie in this primate after an
incubation period compatible with its lifespan complements the study conducted
in transgenic (humanized) mice; taken together these studies suggest that some
isolates of sheep scrapie can promote misfolding of the human prion protein and
that scrapie can develop within the lifespan of some primate species.
In addition to previous studies on scrapie transmission to primate1,8,9 and
the recently published study on transgenic humanized mice13, our results
constitute new evidence for recommending that the potential risk of scrapie for
human health should not be dismissed. Indeed, human PrP transgenic mice and
primates are the most relevant models for investigating the human transmission
barrier. To what extent such models are informative for measuring the zoonotic
potential of an animal TSE under field exposure conditions is unknown. During
the past decades, many protective measures have been successfully implemented to
protect cattle from the spread of c-BSE, and some of these measures have been
extended to sheep and goats to protect from scrapie according to the principle
of precaution. Since cases of c-BSE have greatly reduced in number, those
protective measures are currently being challenged and relaxed in the absence of
other known zoonotic animal prion disease. We recommend that risk managers
should be aware of the long term potential risk to human health of at least
certain scrapie isolates, notably for lymphotropic strains like the classical
scrapie strain used in the current study. Relatively high amounts of infectivity
in peripheral lymphoid organs in animals infected with these strains could lead
to contamination of food products produced for human consumption. Efforts should
also be maintained to further assess the zoonotic potential of other animal
prion strains in long-term studies, notably lymphotropic strains with high
prevalence like CWD, which is spreading across North America, and atypical/Nor98
scrapie (Nor98)50 that was first detected in the past two decades and now
represents approximately half of all reported cases of prion diseases in small
ruminants worldwide, including territories previously considered as scrapie
free. Even if the prevailing view is that sporadic CJD is due to the spontaneous
formation of CJD prions, it remains possible that its apparent sporadic nature
may, at least in part, result from our limited capacity to identify an
environmental origin.
spontaneous atypical BSE ???
if that's the case, then France is having one hell of an epidemic of
atypical BSE, probably why they stopped testing for BSE, problem solved $$$
As of December 2011, around 60 atypical BSE cases have currently been
reported in 13 countries, *** with over one third in France.
so 20 cases of atypical BSE in France, compared to the remaining 40 cases
in the remaining 12 Countries, divided by the remaining 12 Countries, about 3+
cases per country, besides Frances 20 cases. you cannot explain this away with
any spontaneous BSe. ...TSS
Sunday, October 5, 2014
France stops BSE testing for Mad Cow Disease
Thursday, July 24, 2014
*** Protocol for further laboratory investigations into the distribution of
infectivity of Atypical BSE SCIENTIFIC REPORT OF EFSA New protocol for Atypical
BSE investigations
snip...
IBNC Tauopathy or TSE Prion disease, it appears, no one is sure
Posted by flounder on 03 Jul 2015 at 16:53 GMT
Wednesday, July 15, 2015
Additional BSE TSE prion testing detects pathologic lesion in unusual brain
location and PrPsc by PMCA only, how many cases have we missed?
HOUND STUDY
*** AS implied in the Inset 25 we must not _ASSUME_ that transmission of
BSE to other species will invariably present pathology typical of a scrapie-like
disease. ***
snip...
full text ;
Saturday, July 18, 2015
SPONTANEOUS TRANSMISSIBLE SPONGIFORM ENCEPHALOPATHY TSE PRION AKA MAD COW
TYPE DISEASE, DOES IT EXIST NATURALLY IN THE FIELD?
Wednesday, July 15, 2015
Additional BSE TSE prion testing detects pathologic lesion in unusual brain
location and PrPsc by PMCA only, how many cases have we missed?
Article
Evaluation of the Zoonotic Potential of Transmissible Mink
Encephalopathy
Emmanuel E. Comoy 1,*, Jacqueline Mikol 1, Marie-Madeleine Ruchoux 1,
Valérie Durand 1, Sophie Luccantoni-Freire 1, Capucine Dehen 1, Evelyne Correia
1, Cristina Casalone 2, Juergen A. Richt 3, Justin J. Greenlee 4, Juan Maria
Torres 5, Paul Brown 1 and Jean-Philippe Deslys 1
1 CEA, Institute of Emerging Diseases and Innovative Therapies (iMETI),
Division of Prions and Related Diseases (SEPIA), Route du Panorama, BP6, 92265
Fontenay-aux-Roses, France; E-Mails: jacqueline.mikol@wanadoo.fr (J.M.);
mruchoux@yahoo.fr (M.-M.R.); valerie.durand@cea.fr (V.D.);
sophie.luccantoni@cea.fr (S.L.); capucine.dehen@cea.fr (C.D.);
evelyne.correia@cea.fr (E.C.); paulwbrown@comcast.net (P.B.); jpdeslys@cea.fr
(J-P.D.)
2 Istituto Zooprofilattico Sperimentale del Piemonte, Via Bologna 148,
10154 Torino, Italy; E-Mail: cristina.casalone@izsto.it (C.C.)
3 Kansas State University, College of Veterinary Medicine, K224B Mosier
Hall, Manhattan, Kansas 66506-5601 USA; E-Mail: jricht@vet.k-state.edu
4 National Animal Disease Center, USDA, Agricultural Research Service, 1920
Dayton Ave, Ames, Iowa 50010 USA; E-Mail: justin.greenlee@ars.usda.gov
(J.J.G.)
5 Instituto Nacional de Investigacion y Tecnologia Agraria y Alimentaria,
Madrid, Spain; E-mail: jmtorres@inia.es
* Author to whom correspondence should be addressed; E-Mail:
emmanuel.comoy@cea.fr (E.E.C.); Tel.: +33-46-54-90-05; Fax:
+33-46-54-93-19.
Received: 27 June 2013; in revised form: 28 July 2013 / Accepted: 30 July
2013 / Published: 30 July 2013
Abstract: Successful transmission of Transmissible Mink Encephalopathy
(TME) to cattle supports the bovine hypothesis for the still controversial
origin of TME outbreaks. Human and primate susceptibility to classical Bovine
Spongiform Encephalopathy (c-BSE) and the transmissibility of L-type BSE to
macaques indicate a low cattle-to-primate species barrier. We therefore
evaluated the zoonotic potential of cattle-adapted TME. In less than two years,
this strain induced in cynomolgus macaques a neurological disease similar to
L-BSE but distinct from c-BSE. TME derived from another donor species (raccoon)
induced a similar disease with even shorter incubation periods. L-BSE and
cattle-adapted TME were also transmissible to transgenic mice expressing human
prion protein (PrP). Secondary transmissions to transgenic mice expressing
bovine PrP maintained the features of the three tested bovine strains (cattle
TME, c-BSE and L-BSE) regardless of intermediate host. Thus, TME is the third
animal prion strain transmissible to both macaques and humanized transgenic
mice, suggesting zoonotic potentials that should be considered in the risk
analysis of animal prion diseases for human health. Moreover, the similarities
between TME and L-BSE are highly suggestive of a link between these strains, and
therefore the possible presence of L-BSE for many decades prior to its
identification in USA and Europe.
OPEN ACCESS Pathogens 2013, 2 521
snip...
4. Conclusions
We have shown that cattle-adapted TME is the third cattle prion strain
(joining classical and L-type BSE) to be transmissible both to non-human
primates and transgenic mice overexpressing human PrP. However, the successful
transmission of raccoon TME to primate, inducing a disease with similar features
as cattle TME, extends this notion to TME-related strains independent of host
origin. Pathological, biochemical and bioassay investigations converged to
demonstrate the similarity between cattle-adapted TME and L-BSE. Together with
previous experiments performed in ovinized and bovinized transgenic mice and
hamsters [8,9] indicating similarities between TME and L-BSE, the data support
the hypothesis that L-BSE could be the origin of the TME outbreaks in North
America and Europe during the mid-1900s. The corollary of this notion is the
longstanding existence of atypical bovine prion cases in those countries during
the same period, if not earlier. Although the risk of L-BSE for public health
must be further assessed through studies using the oral route of exposure before
drawing definitive conclusions, these data underline the importance of a
potential zoonotic risk of L-BSE in the management of consumer protection,
particularly in the context of the current relaxation of European policy with
respect to BSE.
Pathogens 2013, 2 530
Keywords: primate; prion; transgenic mice; TME; cattle; raccoon; zoonotic
potential
Evidence That Transmissible Mink Encephalopathy Results from Feeding
Infected Cattle
Over the next 8-10 weeks, approximately 40% of all the adult mink on the
farm died from TME.
snip...
The rancher was a ''dead stock'' feeder using mostly (>95%) downer or
dead dairy cattle...
In Confidence - Perceptions of unconventional slow virus diseases of
animals in the USA - APRIL-MAY 1989 - G A H Wells
3. Prof. A. Robertson gave a brief account of BSE. The US approach was to
accord it a very low profile indeed. Dr. A Thiermann showed the picture in the
''Independent'' with cattle being incinerated and thought this was a fanatical
incident to be avoided in the US at all costs. ...
***thus questioning the origin of human sporadic cases.
Thursday, July 24, 2014
*** Protocol for further laboratory investigations into the distribution of
infectivity of Atypical BSE SCIENTIFIC REPORT OF EFSA New protocol for Atypical
BSE investigations
*** 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...TSS
===============
*** LATE-BREAKING ABSTRACTS PRION 2015 CONFERENCE ***
O18
Zoonotic Potential of CWD Prions
Liuting Qing1, Ignazio Cali1,2, Jue Yuan1, Shenghai Huang3, Diane Kofskey1,
Pierluigi Gambetti1, Wenquan Zou1, Qingzhong Kong1 1Case Western Reserve
University, Cleveland, Ohio, USA, 2Second University of Naples, Naples, Italy,
3Encore Health Resources, Houston, Texas, USA
Chronic wasting disease (CWD) is a widespread and expanding prion disease
in free-ranging and captive cervid species in North America. The zoonotic
potential of CWD prions is a serious public health concern. Current literature
generated with in vitro methods and in vivo animal models (transgenic mice,
macaques and squirrel monkeys) reports conflicting results. The susceptibility
of human CNS and peripheral organs to CWD prions remains largely unresolved. In
our earlier bioassay experiments using several humanized transgenic mouse lines,
we detected protease-resistant PrPSc in the spleen of two out of 140 mice that
were intracerebrally inoculated with natural CWD isolates, but PrPSc was not
detected in the brain of the same mice. Secondary passages with such
PrPSc-positive CWD-inoculated humanized mouse spleen tissues led to efficient
prion transmission with clear clinical and pathological signs in both humanized
and cervidized transgenic mice. Furthermore, a recent bioassay with natural CWD
isolates in a new humanized transgenic mouse line led to clinical prion
infection in 2 out of 20 mice. ***These results indicate that the CWD prion has
the potential to infect human CNS and peripheral lymphoid tissues and that there
might be asymptomatic human carriers of CWD infection.
==================
***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.***
==================
Saturday, May 30, 2015
PRION 2015 ORAL AND POSTER CONGRESSIONAL ABSTRACTS
Thursday, August 12, 2010
Seven main threats for the future linked to prions
***Also, a link is suspected between atypical BSE and some apparently
sporadic cases of Creutzfeldt-Jakob disease in humans. These atypical BSE cases
constitute an unforeseen first threat that could sharply modify the European
approach to prion diseases.
Second threat
snip...
Monday, October 10, 2011
EFSA Journal 2011 The European Response to BSE: A Success Story
snip...
*** but the possibility that a small proportion of human cases so far
classified as "sporadic" CJD are of zoonotic origin could not be excluded.
Moreover, transmission experiments to non-human primates suggest that some TSE
agents in addition to Classical BSE prions in cattle (namely L-type Atypical
BSE, Classical BSE in sheep, transmissible mink encephalopathy (TME) and chronic
wasting disease (CWD) agents) might have zoonotic potential.
snip...
***In addition, non-human primates are specifically susceptible for
atypical BSE as demonstrated by an approximately 50% shortened incubation time
for L-type BSE as compared to C-type. Considering the current scientific
information available, it cannot be assumed that these different BSE types pose
the same human health risks as C-type BSE or that these risks are mitigated by
the same protective measures.
Thursday, June 04, 2015
Catholic Medical Center v. Civil No. 14-cv-180-JL Opinion No. 2015 DNH 110
Fireman’s Fund Insurance Company Creutzfeldt Jakob Disease TSE Prion tainted
medical instruments
UNITED STATES DISTRICT COURT DISTRICT OF NEW HAMPSHIRE
Tuesday, May 26, 2015
Minimise transmission risk of CJD and vCJD in healthcare settings Last
updated 15 May 2015
2015 PRION CONFERENCE
*** RE-P.164: Blood transmission of prion infectivity in the squirrel
monkey: The Baxter study
***suggest that blood donations from cases of GSS (and perhaps other
familial forms of TSE) carry more risk than from vCJD cases, and that little or
no risk is associated with sCJD. ***
ran across an old paper from 1984 ;
***The occurrence of contact cases raises the possibility that transmission
in families may be effected by an unusually virulent strain of the agent.
***
***suggest that blood donations from cases of GSS (and perhaps other
familial forms of TSE) carry more risk than from vCJD cases, and that little or
no risk is associated with sCJD...see;
P.164: Blood transmission of prion infectivity in the squirrel monkey: The
Baxter study
Paul Brown1, Diane Ritchie2, James Ironside2, Christian Abee3, Thomas
Kreil4, and Susan Gibson5 1NIH (retired); Bethesda, MD USA; 2University of
Edinburgh; Edinburgh, UK; 3University of Texas; Bastrop, TX USA; 4Baxter
Bioscience; Vienna, Austria; 5University of South Alabama; Mobile, AL USA
Five vCJD disease transmissions and an estimated 1 in 2000 ‘silent’
infections in UK residents emphasize the continued need for information about
disease risk in humans. A large study of blood component infectivity in a
non-human primate model has now been completed and analyzed. Among 1 GSS, 4
sCJD, and 3 vCJD cases, only GSS leukocytes transmitted disease within a 5–6
year surveillance period. A transmission study in recipients of multiple whole
blood transfusions during the incubation and clinical stages of sCJD and vCJD in
ic-infected donor animals was uniformly negative. These results, together with
other laboratory studies in rodents and nonhuman primates and epidemiological
observations in humans, ***suggest that blood donations from cases of GSS (and
perhaps other familial forms of TSE) carry more risk than from vCJD cases, and
that little or no risk is associated with sCJD. The issue of decades-long
incubation periods in ‘silent’ vCJD carriers remains open.
=============
***suggest that blood donations from cases of GSS (and perhaps other
familial forms of TSE) carry more risk than from vCJD cases, and that little or
no risk is associated with sCJD...see;
Wednesday, December 11, 2013
*** Detection of Infectivity in Blood of Persons with Variant and Sporadic
Creutzfeldt-Jakob Disease ***
THE BAXTER STUDY...SEE MORE HERE ;
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
snip...
THE BAXTER STUDY...SEE MORE HERE ;
Wednesday, July 01, 2015
DRAFT Virginia Deer Management Plan 2015-2024 (bans urine scents do to CWD
2015)
Tuesday, July 21, 2015
Texas CWD Medina County Herd Investigation Update July 16, 2015
TSS
posted by Terry S. Singeltary Sr. at
6:55 PM
0 Comments:
Post a Comment
Subscribe to Post Comments [Atom]
<< Home