From: TSS ()
Subject: PROCEEDINGS ONE HUNDRED AND TENTH ANNUAL MEETING of the UNITED STATES ANIMAL HEALTH ASSOCIATION 2006-2007
Date: May 25, 2007 at 7:59 am PST
PROCEEDINGS ONE HUNDRED AND TENTH ANNUAL MEETING of the UNITED STATES ANIMAL
HEALTH ASSOCIATION 2006-2007
United States Animal
Drs. Dean Goeldner and Tom Gidlewski, VS-APHIS-USDA, presented
the APHIS-VS chronic wasting disease (CWD) program update. CWD has
been discovered in free-ranging cervids in 11 states and 41 captive cervid
herds in nine states. There are currently four infected elk herds and one
infected white-tailed deer herd that have chosen to remain under quarantine
instead of depopulate. In 2006, the CWD program depopulated one elk
herd in the endemic area which turned out to be infected as well as a
chronically infected white-tailed deer herd and a mixed elk and white-tailed
deer herd for a total of approximately 110 animals. For the last three years,
the program has paid for testing about 15,000 captive cervids per year.
Demand for testing is expected to increase with the implementation of the
program. The first infected free-ranging white-tailed deer was found in northwest
Kansas in 2006. On the positive side, New York found no additional
positive free-ranging cervids in 2006 but West Virginia found four additional
animals in Hampshire County. Wisconsin continues to aggressively battle
CWD with over 100,000 animals submitted for testing since 2000 and over
650 positive deer identified. The infected area appears to be largely limited
to the original counties. Interestingly, the number of deer in the Wisconsin
endemic area does not appear to be decreasing despite the large number
of animals that have been removed. Colorado has stopped culling deer in
“hot spots” as they believe that it was not very successful. Alberta, Canada
continues to find more positive white-tailed deer adjacent to the infected
Appropriate tissue collection and submission for CWD diagnosis includes
obex, medial retropharygeal lymph nodes and palatine tonsils.
Submission of an ear with the official eartag attached or submission of
fresh tissue accompanied by an appropriately executed chain of evidence
document will allow DNA comparison in the event of a positive diagnosis.
Archiving herd blood samples on special collection cards is also a way to
compare DNA in the event of a positive diagnosis in the future. All positive
cases are verified by two pathologists and the presumptive positive tissues
are completely retested at the National Veterinary Services Laboratory
(NVSL). Rectal biopsy continues to be examined as a tool for CWD antemortem
diagnosis. Hundreds of animals have been examined and the
results look promising. Larger numbers need to be examined in order to
make final conclusions. Retrospective epidemiologic analysis and transgenic
mouse research in 2006 still support the theory that CWD does not appear
to affect people or non-cervids animals.
APHIS received approximately $18.5 million in appropriated CWD funding
in FY 2006 including $2.44 million in congressional earmarks. The FY
2007 appropriations have not been passed by Congress; the president’s
budget requests $15.4 million for CWD. On July 21, 2006, APHIS published
its final CWD rule. The final rule added moose and all Cervus species
to the previously announced deer and elk species covered in the herd
certification program. It expanded the term “captive” to “farmed and captive”,
maintained a five-year surveillance standard for surveillance, clarified
that two positive official tests are needed for a CWD diagnosis, reduced the
minimum testing age to 12 months, adjusted commingling buffers, eliminated
the 48-hour exemption for short-term commingling, changed the identification
(ID) requirement to one official ID and one ID unique within the
herd, and added the reporting of escapes and disappearances.
Grandfathering of state programs will be accomplished through Memorandum
of Understanding (MOUs) with the states followed by reviews of state
programs for consistency with federal requirements. The interstate movement
requirements maintained a “ramping up” process to reach the fiveyear
surveillance standard. An exemption was created for direct movement
to slaughter. A permit will be required for interstate movement of research
animals and two IDs will be required for wild cervids captured for translocation
and release. Subsequent to publication of the rule, three petitions
were received from organizations representing state agencies and officials
challenging the interstate movement provisions in the rule and requesting a
stay in the rule’s implementation. The petitions challenged the scientific
basis for initially allowing the interstate movement of animals with only one
or two years of surveillance. They also took issue with the federal preemption
language in the rule. According to USDA legal counsel, federal preemption
on interstate movement is implicit in all APHIS regulations; it was
made explicit in this case in response to a comment on the proposed rule.
Nevertheless, APHIS believes the petitions merit further consideration. On
September 8, 2006, APHIS published a notice of delay of implementation
for the rule. The petitions will be published soon for public comment. APHIS
intends to resolve the issues quickly so that a final rule can be implemented
as the state-federal-industry program it is intended to be.
Dr. Robert Kunkle, National Animal Disease Center (NADC), Agricultural
Research Center (ARS), USDA, presented a time-specific Committee
paper entitled “Experimental Transmission of Chronic Wasting Disease
(CWD) of Elk ( Cervus elapus nelsoni), White-tailed Deer ( Odocoileus
virginianus), and Mule Deer ( Odocoileus hemionus hemionus) to White
tailed Deer by Intracerebral Route. This paper is included in its entirety in
Dr. Michael Miller, Senior Wildlife Veterinarian, Colorado Division of
Wildlife, provided an overview of recent progress in understanding various
aspects of chronic wasting disease (CWD) epidemiology, diagnosis, and
control. Dr. Miller used the occurrence of CWD in a moose to hypothesize
that the potential natural host range of CWD may be predicted based on
similarities between the native prion protein of known hosts (deer, wapiti,
and moose) and other cervid species. He also reviewed findings related to
CWD transmission and showed that simulation models of epidemic dynamics
based on relatively simple transmission assumptions suggest that
CWD is likely to persist in wild deer populations and depress population
performance over time. Dr. Miller next described highlights of a new study
on PrPCWD distribution in experimentally-infected mule deer that demonstrated
marked genetic effects on CWD progression but not susceptibility
in this species, and discussed the potential implications for CWD epidemiology.
He then shared preliminary data on use of rectal mucosa biopsy to
detect CWD infections in live white-tailed and mule deer, which suggest
that rectal biopsy likely will be a useful herd screening test and surveillance
tool provided PrP genotype data are available for sampled individuals. Dr.
Miller concluded his presentation with a brief summary of unsuccessful
attempts to control CWD in north central Colorado, emphasizing the challenges
and obstacles that likely make eradication of CWD from the wild
infeasible given present technology.
EXPERIMENTAL TRANSMISSION OF CHRONIC
WASTING DISEASE (CWD) OF ELK (CERVUS
ELAPHUS NELSONI), WHITE-TAILED DEER
(ODOCOILEUS VIRGINIANUS), AND MULE DEER
(ODOCOILEUS HEMIONUS HEMIONUS) TO WHITETAILED
DEER BY INTRACEREBRAL ROUTE
R.A. Kunkle, A.N. Hamir, J.M. Miller, J.A. Richt, J.J. Greenlee
National Animal Disease Center
Agriculture Research Service
United States Department of Agriculture
National Veterinary Services Laboratories
Animal and Plant Health Inspection Service
United States Department of Agriculture
Wyoming Veterinary Laboratory
University of Wyoming
Chronic wasting disease (CWD) is a transmissible spongiform encephalopathy
(TSE) affecting elk, white-tailed deer, and mule deer. Intra-species
transmission of CWD is readily accomplished via oral administration of
CWD-affected brain, and while the exact mode of natural transmission is
unclear, horizontal transmission within species has been demonstrated.
The TSE’s are prion-associated diseases. Different prion strains are associated
with variations in clinical course and pathology in susceptible animal
hosts. To determine the potential existence of CWD pathotype strain differences,
groups of five white-tailed deer were inoculated by intracerebral
route (IC) with 1 ml of 10% (wt/vol) brain homogenates derived from CWDaffected
elk, white-tailed deer, or mule deer. Two non-inoculated deer served
as negative controls. All deer were homozygous at PrP gene polymorphic
sites 95 (glutamine) and 138 (serine). Deer homozygous (glycine/glycine)
or heterozygous (glycine/serine) at codon 96 were approximately equally
divided between treatment groups. One deer from each treatment group
was euthanized 10 months post-inoculation (PI); findings for these three
deer were similar and included limited or mild spongiform encephalopathy
(SE) and immunohistochemical (IHC) detection of prion in lymphoid tissue
follicles and in the CNS, especially in subependymal areas. All remaining
deer were euthanized at the terminal stage of disease. The clinical course
of CWD appeared similar between groups. The survival period did not differ
between groups, ranging from 14 to 26 months, with an average mean of 20
months. The severity of SE and magnitude of IHC staining appeared proportional
to incubation period. Microscopic lesions in the CNS were typical
of previously reported CWD and SE, including the presence of cerebral
florid plaques. IHC staining was multifocally extensive to diffuse, and was
perineuronal, subependymal, and neuropil associated. Staining was pronounced
in the midbrain, but relatively sparse in the hippocampus. Differences
in histopathologic and IHC findings between groups were not noted.
Negative control deer sacrificed at 26 months PI did not have SE and were
IHC negative. The composite findings indicate the clinical course and pathology
of CWD in IC challenged white-tailed deer was not influenced by
species of the inoculum source or by PrP gene polymorphism at codon 96
REPORT OF THE COMMITTEE ON
Chair: Kevin G. Custer, Des Moines, IA
Vice Chair: Richard Sellers, Arlington, VA
David C. Ailor, DC; Roy D. Brister, AR; Eric C. Gonder, NC; C. Ross
Hamilton, TX; Jay Hawley, IN; Larry E. Hendricks, IL; Tom Holder, MD;
Rex D. Holt, GA; David C. Kradel, PA; Elizabeth A. Lautner, IA; Gerald G.
May, OH; David L. Meeker, VA; Gary D. Osweiler, IA; Jane F. Robens,
MD; James E. Stocker, NC; H. Wesley Towers, DE; Elizabeth K. Wagstrom,
IA; W. Douglas Waltman, GA; Gary L. Waters, MT.
The Committee met at the Minneapolis Hilton Hotel, Minneapolis, Minnesota,
Monday, October 16, 2006, 1:00-6:00 p.m., LaSalle Room. Twentythree
members and guests were present.
Dr. Burt Pritchett, Center for Veterinary Medicine (CVM), Food and
Drug Administration (FDA), gave an update on agency activities relative to
bovine spongiform encephalopathy (BSE), the Animal Feed Safety System
(AFSS) and contaminant limits.
• BSE – The proposed rule (589.2001) to enhance the “feed rule”
was published on October 6, 2005. CVM remains committed to
publishing a final rule, but it is unlikely that publication will take
place this year. FDA agrees that the economic impact was under
estimated and is conducting a new economic evaluation. Carcass
disposal is a major issue and revisions are needed relative to the
• AFSS – is a comprehensive, risk-based system for feed
manufacture and distribution to minimize risks to animal and human
health. It is intended to tie together regulation, policy and guidance.
The goal is to complete the AFSS by the end of 2007.
• Contaminant Limits – There is a lack of process for distinguishing
feed hazards based upon their relative risks (Risk = Hazard x
Exposure). The Feed Contaminants Program is scheduled for
completion in 2010.
Dr. Aaron Scott, Veterinary Services (VS), Animal and Plant Health
Inspection Service (APHIS), United States Department of Agriculture (USDA)
gave an update on BSE surveillance activities. To date, 189,000+ cases of
BSE have been diagnosed. Of those, 89 percent occurred prior to 1997,
and more than 96 percent have occurred in the United Kingdom (UK). USDA
has conducted active surveillance since 1990. Surveillance is to monitor
the presence of the disease in cattle, not to identify every case. The
enhanced surveillance program began in June 2004 and ended in August 2006.
More than 785,000 samples were analyzed. Two positive samples were
identified. The conclusion of the enhanced surveillance program is that
BSE prevalence is less than one infected animal per one million adult cattle.
Dr. Scott emphasized the importance of clinical history accompanying
samples, as those samples will carry more relative weight in the analysis
of the data.
Dr. Eric Nelson, President, American Association of Feed Control Officials
(AAFCO), gave an update on association activities. AAFCO’s Model
Feed Safety Program is designed to elevate the scope and effectiveness of
current laws and regulations, and emerging systems and practices. The
program will fill in the gaps of regulations and increase stakeholder participation.
Richard Sellers, Vice President, American Feed Industry Association
(AFIA), gave an update on the association’s Safe Feed/Safe Food program.
The association is also monitoring European Union (EU) 183, which
could put Hazard Analysis and Critical Control Point (HACCP) requirements
on feed ingredients imported into the EU.
Dr. David Meeker, Vice President, National Renderers Association
(NRA), gave an update on the association’s Code of Practice Certification
for rendering facilities, and rendered animal product blending facilities.
Mr. Richard Sellers, AFIA introduced a new business item questioning
the relevancy of the Committee on Feed Safety? Chair Custer responded
that the relevance of a Committee is based upon issues addressed and
resolutions generated. Only six of the twenty-two committee members
attended the meeting. Discussions included the importance and need for a
standing Committee on Feed Safety or could the Committee issues be
distributed to another Committee. The Chair will be working with USAHA’s
Executive Committee in reviewing how best to address the feed safety
issues at USAHA.
FOREIGN AND EMERGING DISEASES
WHAT IS IT AND WHAT IS THE SIGNIFICANCE
Linda A. Detwiler, Paul Brown, Lisa M. McShane, and Gianluigi Zanusso
For almost the entire two decades that BSE has been known in the
world it was thought that there was only one “strain” that infected cattle and
caused disease in some other species such as humans (Bruce, et al.,
1997; Hill, et al., 1997; Casalone, et al., 2004). We now know that there
are other manifestations of prion diseases in cattle which have been termed
atypical BSE. Atypical BSE is a study in progress with more unknowns
than knowns. One of the most important of the unknowns is the significance
of atypical BSE in regard to human and animal health.
Previous research in mice had suggested the existence of a number of
scrapie strains. Historically, research involving the differentiation of Transmissible
Spongiform Encephalopathy (TSE) strains was based on biological
typing using panels of inbred mice inoculated with homogenates of
infected tissues. If the mice developed a TSE it was characterized by
length of incubation and lesion pattern in the brain. (Bruce et al. 1992;
Bruce et al. 1994) More recently it has been determined that the human
and animals variations may be biochemically differentiated on the basis of
molecular mass of the protease resistant prion protein (PrPres) and the
degree of glycosylation (Collinge, et al., 1996)
In 2004, cases of a bovine prion disease molecularly different than
already documented as classical BSE were described by scientists in both
Italy (Casalone, et al., 2004) and France (Biacabe, et al., 2004). In both
countries the cattle were over 8 years of age. The Italian cases (11 and 15
years of age) originally named bovine amyloidotic spongiform encephalopathy
(BASE) were characterized by an unglycosylated protein band with
a lower molecular mass (thus named L cases) and the predominance of
the monoglycosylated band. In addition, immunohistochemical detection
of PrPres in these cases found greater deposits in the cerebral cortex and
thalamus versus the brain stem. The French cases found a higher molecular
mass associated with the unglycosylated protein band and were
called H cases (see figure 1). The different “strains” are now called atypical
REPORT OF THE COMMITTEE
Since these 2 publications additional cases of atypical BSE have been
found in other countries. H cases have been detected in Canada, France,
Germany, Japan, the Netherlands, Poland, Sweden, Switzerland and the
United States. L cases have been diagnosed in Belgium, Denmark, France,
Germany, Italy, Japan and Poland (Brown, et al., 2006). The L cases in
Belgium and Japan had additional differences (Yamakawa, et al., 2003; De
Bosschere, et al., 2004). Two important points must be emphasized
regarding the atypical BSE cases. Information regarding lesion pattern
and PrP distribution is very limited as most cases were detected by the
large-scale surveillance programs which only required collection of the brain
stem. In addition, if countries were using certain tests, some cases of
atypical BSE may have been misdiagnosed or reported as negative. For
example, if a country relied solely on immunohistochemistry to confirm
positive ELISA screening test cases and did not use western blotting at all,
the banding pattern differences would go unnoticed.
This may explain why the United Kingdom has not detected any cases
of atypical BSE to date. The use of the western blot test was introduced to
confirm BSE cases detected through passive surveillance only in 2000 and
for active surveillance cases in 2001. The Department for Environment,
Food and Rural Affairs (DEFRA) is conducting a retrospective study to
examine if any of the cases diagnosed in the past did in fact have an
When atypical cases were first reported there was some speculation
that these may merely be protein accumulation disorders associated with
old age. It has now been shown that both the L and H types of atypical
BSE are at least experimentally transmissible. Homogenates from L cases
have been transmitted to bovinized transgenic mice, humanized transgenic
Figure 1. Comparison of Western Blot patterns from classical BSE and L
and H atypical BSE. (Reprinted from Brown, et. al. 2006)
FOREIGN AND EMERGING DISEASES
mice, Cynomolgus monkeys and 1 breed of cattle (Buschmann, et al. 2006;
Book of abstracts (2006), International Conference on Prion Diseases, Turin,
Italy). H cases have been transmitted to bovinized transgenic (Tgbov) and
ovinized transgenic mice (Béringue, et al. 2006). The incubation times for
atypical L cases of BSE were shorter in the Tgbov mice than classical BSE
inoculated into Tgbov mice and the H cases had longer incubations.
There are several theories on the origin of atypical BSE:
• A variation or mutation of the classical BSE strain
• A different route of exposure or exposure at an older age
• A strain of Scrapie transmitted to cattle
• Sporadic or a spontaneous occurrence of BSE
At his point in time, there is no evidence to conclude that any of the
theories are or are not a possibility. There is considerable interest in the
sporadic theory. If a form of BSE were to occur naturally, this may suggest
that certain control and prevention measure would have to remain in place
indefinitely. Proving or disproving the occurrence of a relatively rare sporadic
disease poses a significant challenge. It would require between 3
and 4.5 million tests performed on brain samples randomly taken from
cattle over 7 years of age in a country with no evidence of risk from orally
acquired BSE. It is unlikely that any country would have the will or resources
to perform such a study. Lacking this type of evidence, systematic
surveillance over a long time period may provide evidence about the
nature of atypical BSE.
As previously stated most of the characteristics of atypical BSE have
not been defined. In addition to the origin, the risk to other cattle by means
of natural transmission, the risk to humans and other animal species such
as chickens and pigs is still unknown as is the distribution of infectivity
throughout the body of a bovine. There is little information on clinical
manifestation if it occurs at all in certain of the cases. Documented L
cases have been diagnosed from samples taken from older “healthy” cattle
presented for routine slaughter.
While additional surveillance and research is being conducted, it is
important for policy makers to consider the implications of atypical BSE.
They may need to rethink what populations are appropriate targets. It
would probably be unwise to prematurely lessen or discontinue the current
BSE protection measures.
Acknowledgement: A special thanks to Dr. Danny Matthews, UK,
DEFRA for the information regarding the UK BSE testing schemes.
see full text 757 pages ;
sadly, Dr. Detwiler et al failed to mention the most important aspect of atypical BSE and or BASE ;
USA MAD COW STRAIN MORE VIRULENT TO HUMANS THAN UK STRAIN
18 January 2007 - Draft minutes of the SEAC 95 meeting (426 KB) held on 7
December 2006 are now available.
64. A member noted that at the recent Neuroprion meeting, a study was
presented showing that in transgenic mice BSE passaged in sheep may be more
virulent and infectious to a wider range of species than bovine derived BSE.
Other work presented suggested that BSE and bovine amyloidotic spongiform
encephalopathy (BASE) MAY BE RELATED. A mutation had been identified in the
prion protein gene in an AMERICAN BASE CASE THAT WAS SIMILAR IN NATURE TO A
MUTATION FOUND IN CASES OF SPORADIC CJD.
3:30 Transmission of the Italian Atypical BSE (BASE) in Humanized Mouse
Models Qingzhong Kong, Ph.D., Assistant Professor, Pathology, Case Western Reserve
Bovine Amyloid Spongiform Encephalopathy (BASE) is an atypical BSE strain
discovered recently in Italy, and similar or different atypical BSE cases
were also reported in other countries. The infectivity and phenotypes of
these atypical BSE strains in humans are unknown. In collaboration with
Pierluigi Gambetti, as well as Maria Caramelli and her co-workers, we have
inoculated transgenic mice expressing human prion protein with brain
homogenates from BASE or BSE infected cattle. Our data shows that about half
of the BASE-inoculated mice became infected with an average incubation time
of about 19 months; in contrast, none of the BSE-inoculated mice appear to
be infected after more than 2 years.
***These results indicate that BASE is transmissible to humans and suggest that BASE is more virulent than
classical BSE in humans.***
6:30 Close of Day One
SEE STEADY INCREASE IN SPORADIC CJD IN THE USA FROM
1997 TO 2006. SPORADIC CJD CASES TRIPLED, with phenotype
of 'UNKNOWN' strain growing. ...
There is a growing number of human CJD cases, and they were presented last
week in San Francisco by Luigi Gambatti(?) from his CJD surveillance
He estimates that it may be up to 14 or 15 persons which display selectively
SPRPSC and practically no detected RPRPSC proteins.
and about CWD to humans, and the risk there of ;
The lack of evidence of a link between CWD transmission and unusual cases of
CJD, despite several epidemiologic investigations, and the absence of an
increase in CJD incidence in Colorado and Wyoming suggest that the risk, if
any, of transmission of CWD to humans is low. Although the in vitro studies
indicating inefficient conversion of human prion protein by CWD-associated
prions raise the possibility of low-level transmission of CWD to humans, no
human cases of prion disease with strong evidence of a link with CWD have
been identified. However, the transmission of BSE to humans and the
resulting vCJD indicate that, provided sufficient exposure, the species
barrier may not completely protect humans from animal prion diseases.
Because CWD has occurred in a limited geographic area for decades, an
adequate number of people may not have been exposed to the CWD agent to
result in a clinically recognizable human disease. The level and frequency
of human exposure to the CWD agent may increase with the spread of CWD in
the United States. Because the number of studies seeking evidence for CWD
transmission to humans is limited, more epidemiologic and laboratory studies
should be conducted to monitor the possibility of such transmissions.
Studies involving transgenic mice expressing human and cervid prion protein
are in progress to further assess the potential for the CWD agent to cause
human disease. Epidemiologic studies have also been initiated to identify
human cases of prion disease among persons with an increased risk for
exposure to potentially CWD-infected deer or elk meat (47). If such cases
are identified, laboratory data showing similarities of the etiologic agent
to that of the CWD agent would strengthen the conclusion for a causal link.
Surveillance for human prion diseases, particularly in areas where CWD has
been detected, remains important to effectively monitor the possible
transmission of CWD to humans. Because of the long incubation period
associated with prion diseases, convincing negative results from
epidemiologic and experimental laboratory studies would likely require years
of follow-up. In the meantime, to minimize the risk for exposure to the CWD
agent, hunters should consult with their state wildlife agencies to identify
areas where CWD occurs and continue to follow advice provided by public
health and wildlife agencies. Hunters should avoid eating meat from deer and
elk that look sick or test positive for CWD. They should wear gloves when
field-dressing carcasses, bone-out the meat from the animal, and minimize
handling of brain and spinal cord tissues. As a precaution, hunters should
avoid eating deer and elk tissues known to harbor the CWD agent (e.g.,
brain, spinal cord, eyes, spleen, tonsils, lymph nodes) from areas where CWD
has been identified.
From: TSS (216-119-163-189.ipset45.wt.net)
Subject: CWD aka MAD DEER/ELK TO HUMANS ???
Date: September 30, 2002 at 7:06 am PST
From: "Belay, Ermias"
Cc: "Race, Richard (NIH)" ; ; "Belay,
Sent: Monday, September 30, 2002 9:22 AM
Subject: RE: TO CDC AND NIH - PUB MED- 3 MORE DEATHS - CWD - YOUNG HUNTERS
In the Archives of Neurology you quoted (the abstract of which was
attached to your email), we did not say CWD in humans will present like
That assumption would be wrong. I encourage you to read the whole
article and call me if you have questions or need more clarification
(phone: 404-639-3091). Also, we do not claim that "no-one has ever been
infected with prion disease from eating venison." Our conclusion stating
that we found no strong evidence of CWD transmission to humans in the
article you quoted or in any other forum is limited to the patients we
Ermias Belay, M.D.
Centers for Disease Control and Prevention
> > -----Original Message-----
> > From:
> > Sent: Sunday, September 29, 2002 10:15 AM
> > To: [log in to unmask]; [log in to unmask]; [log in to unmask]
> > Subject: TO CDC AND NIH - PUB MED- 3 MORE DEATHS - CWD - YOUNG
> > HUNTERS
Sunday, November 10, 2002 6:26 PM ......snip........end..............TSS
A. Aguzzi - Chronic Wasting Disease (CWD) also needs to be addressed. Most
serious because of rapid horizontal spread and higher prevalence than BSE in
UK, up to 15% in some populations. Also may be a risk to humans - evidence
that it is not dangerous to humans is thin.
JOURNAL OURNAL OF VIROLOGY IROLOGY, Nov. 2005, p. 13794-13796 Vol. 79, No.
0022-538X/05/$08.00 !0 doi:10.1128/JVI.79.21.13794-13796.2005
Copyright © 2005, American Society for Microbiology. All Rights Reserved.
Interspecies Transmission of Chronic Wasting Disease Prions to
Squirrel Monkeys (Saimiri sciureus sciureus)
Richard F. Marsh, 1? Anthony nthony E. Kincaid, 2 Richard A. Bessen, 3 and
Jason C. Bartz Bartz4*
Department of Animal Health and Biomedical Sciences, University of
Wisconsin, Madison 53706 537061; Department of
Physical Therapy Therapy2 and Department of Medical Microbiology and
Immunology, 4 Creighton University, Omaha,
Nebraska 68178; and Department of Veterinary Molecular Biology, Montana
State University, Bozeman, Montana 59718 597183
Received 3 May 2005/Accepted 10 August 2005
Chronic wasting disease (CWD) is an emerging prion disease of deer and elk.
The risk of CWD transmission
to humans following exposure to CWD-infected tissues is unknown. To assess
the susceptibility of nonhuman
primates to CWD, two squirrel monkeys were inoculated with brain tissue from
a CWD-infected mule deer. The
CWD-inoculated squirrel monkeys developed a progressive neurodegenerative
disease and were euthanized at
31 and 34 months postinfection. Brain tissue from the CWD-infected squirrel
monkeys contained the abnormal
isoform of the prion protein, PrP-res, and displayed spongiform
degeneration. This is the first reported
transmission of CWD to primates. ...snip...end
Diagnosis and Reporting of Creutzfeldt-Jakob Disease
Singeltary, Sr et al. JAMA.2001; 285: 733-734.
see full text ;
Colorado Surveillance Program for Chronic Wasting Disease
Transmission to Humans (TWO SUSPECT CASES)
NOW, about scrapie in the USA and the risk factors to humans ;
12/10/76 AGRICULTURAL RESEARCH COUNCIL REPORT OF THE ADVISORY COMMITTE ON
SCRAPIE Office Note CHAIRMAN: PROFESSOR PETER WILDY snip... A The Present
Position with respect to Scrapie A] The Problem Scrapie is a natural disease
of sheep and goats. It is a slow and inexorably progressive degenerative
disorder of the nervous system and it ia fatal. It is enzootic in the United
Kingdom but not in all countries. The field problem has been reviewed by a
MAFF working group (ARC 35/77). It is difficult to assess the incidence in
Britain for a variety of reasons but the disease causes serious financial
loss; it is estimated that it cost Swaledale breeders alone $l.7 M during
the five years 1971-1975. A further inestimable loss arises from the closure
of certain export markets, in particular those of the United States, to
Page 17 of 17
It is clear that scrapie in sheep is important commercially and for that
reason alone effective measures to control it should be devised as quickly
as possible. Recently the question has again been brought up as to whether
scrapie is transmissible to man. This has followed reports that the disease
has been transmitted to primates. One particularly lurid speculation
(Gajdusek 1977) conjectures that the agents of scrapie, kuru,
Creutzfeldt-Jakob disease and transmissible encephalopathy of mink are
varieties of a single "virus". The U.S. Department of Agriculture concluded
that it could "no longer justify or permit scrapie-blood line and
scrapie-exposed sheep and goats to be processed for human or animal food at
slaughter or rendering plants" (ARC 84/77)" The problem is emphasised by the
finding that some strains of scrapie produce lesions identical to the once
which characterise the human dementias" Whether true or not. the hypothesis
that these agents might be transmissible to man raises two considerations.
First, the safety of laboratory personnel requires prompt attention. Second,
action such as the "scorched meat" policy of USDA makes the solution of the
acrapie problem urgent if the sheep industry is not to suffer grievously.
Oral transmission of kuru, Creutzfeldt-Jakob disease, and scrapie to
Gibbs CJ Jr, Amyx HL, Bacote A, Masters CL, Gajdusek DC.
Kuru and Creutzfeldt-Jakob disease of humans and scrapie disease of
sheep and goats were transmitted to squirrel monkeys (Saimiri sciureus) that
were exposed to the infectious agents only by their nonforced consumption of
known infectious tissues. The asymptomatic incubation period in the one
monkey exposed to the virus of kuru was 36 months; that in the two monkeys
exposed to the virus of Creutzfeldt-Jakob disease was 23 and 27 months,
respectively; and that in the two monkeys exposed to the virus of scrapie
was 25 and 32 months, respectively. Careful physical examination of the
buccal cavities of all of the monkeys failed to reveal signs or oral
lesions. One additional monkey similarly exposed to kuru has remained
asymptomatic during the 39 months that it has been under observation.
Subject: SCRAPIE UPDATE USA AS OF MARCH 2007 NOR98 INCLUDED
Date: May 9, 2007 at 6:43 pm PST
SCRAPIE UPDATE USA AS OF MARCH 2007 NOR98 INCLUDED
NOR98-LIKE STRAIN OF SCRAPIE FOUND IN WYOMING (1791 lines)
From: Terry S. Singeltary Sr. <[log in to unmask]>
Date: Wed, 11 Apr 2007 15:08:15 -0500
Published online before print October 20, 2005
Proc. Natl. Acad. Sci. USA, 10.1073/pnas.0502296102
A newly identified type of scrapie agent can naturally infect sheep with resistant PrP genotypes
( sheep prion | transgenic mice )
Annick Le Dur *, Vincent Béringue *, Olivier Andréoletti , Fabienne Reine *, Thanh Lan Laï *, Thierry Baron , Bjørn Bratberg ¶, Jean-Luc Vilotte ||, Pierre Sarradin **, Sylvie L. Benestad ¶, and Hubert Laude *
*Virologie Immunologie Moléculaires and ||Génétique Biochimique et Cytogénétique, Institut National de la Recherche Agronomique, 78350 Jouy-en-Josas, France; Unité Mixte de Recherche, Institut National de la Recherche Agronomique-Ecole Nationale Vétérinaire de Toulouse, Interactions Hôte Agent Pathogène, 31066 Toulouse, France; Agence Française de Sécurité Sanitaire des Aliments, Unité Agents Transmissibles Non Conventionnels, 69364 Lyon, France; **Pathologie Infectieuse et Immunologie, Institut National de la Recherche Agronomique, 37380 Nouzilly, France; and ¶Department of Pathology, National Veterinary Institute, 0033 Oslo, Norway
Edited by Stanley B. Prusiner, University of California, San Francisco, CA, and approved September 12, 2005 (received for review March 21, 2005)
Scrapie in small ruminants belongs to transmissible spongiform encephalopathies (TSEs), or prion diseases, a family of fatal neurodegenerative disorders that affect humans and animals and can transmit within and between species by ingestion or inoculation. Conversion of the host-encoded prion protein (PrP), normal cellular PrP (PrPc), into a misfolded form, abnormal PrP (PrPSc), plays a key role in TSE transmission and pathogenesis. The intensified surveillance of scrapie in the European Union, together with the improvement of PrPSc detection techniques, has led to the discovery of a growing number of so-called atypical scrapie cases. These include clinical Nor98 cases first identified in Norwegian sheep on the basis of unusual pathological and PrPSc molecular features and "cases" that produced discordant responses in the rapid tests currently applied to the large-scale random screening of slaughtered or fallen animals. Worryingly, a substantial proportion of such cases involved sheep with PrP genotypes known until now to confer natural resistance to conventional scrapie. Here we report that both Nor98 and discordant cases, including three sheep homozygous for the resistant PrPARR allele (A136R154R171), efficiently transmitted the disease to transgenic mice expressing ovine PrP, and that they shared unique biological and biochemical features upon propagation in mice. These observations support the view that a truly infectious TSE agent, unrecognized until recently, infects sheep and goat flocks and may have important implications in terms of scrapie control and public health.
Author contributions: H.L. designed research; A.L.D., V.B., O.A., F.R., T.L.L., J.-L.V., and H.L. performed research; T.B., B.B., P.S., and S.L.B. contributed new reagents/analytic tools; V.B., O.A., and H.L. analyzed data; and H.L. wrote the paper.
A.L.D. and V.B. contributed equally to this work.
To whom correspondence should be addressed.
Hubert Laude, E-mail: email@example.com
IT'S very disturbing to me when Gov. officials omit the most important aspect of a study, or other facts that should have been presented in that study, that are of the utmost importanct to the consumer. ...
Terry S. Singeltary Sr.
P.O. Box 42
Bacliff, Texas USA 77518