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From: TSS ()
Subject: CWD NY DEPT OF HEALTH FACTS AND FICTION
Date: April 10, 2005 at 12:42 pm PST

-------- Original Message --------
Subject: CWD NY DEPT OF HEALTH FACTS AND FICTION
Date: Sun, 10 Apr 2005 14:44:06 -0500
From: "Terry S. Singeltary Sr."
To: Bovine Spongiform Encephalopathy
CC: fwwildlf@gw.dec.state.ny.us, rwnp@gw.dec.state.ny.us, essica.chittenden@agmkt.state.ny.us, spclark@utica.gannett.com, news-tips@nytimes.com, executive-editor@nytimes.com, publisher@nytimes.com

Chronic Wasting Disease (CWD)


What is Chronic Wasting Disease (CWD)?

CWD is a disease found in some deer and elk populations, that damages
portions of the brain and typically causes progressive loss of body
condition, behavioral changes, excessive salivation and death. The cause
of the disease is suspected to be a type of prion (protein infectious
particle) that is found in some tissues of infected animals.


Where does CWD occur?

CWD is a disease that is unique to North America. As of March, 2005, CWD
has been found in wild deer and/or elk in Colorado, Illinois, Nebraska,
New Mexico, South Dakota, Utah, Wisconsin, Wyoming, and in the Canadian
province of Saskatchewan. In captive deer and/or elk, it has been found
in Colorado, Kansas, Minnesota, Montana, Nebraska, New York, Oklahoma,
South Dakota, Wisconsin, Wyoming, and in the Canadian provinces of
Alberta and Saskatchewan.


How is CWD transmitted?

Experimental evidence indicates that infected deer and elk probably
transmit the disease through animal-animal contact, maternal
transmission (mother animal to fetus), and/or contamination of feed or
water sources with saliva or bodily waste material. The transmission may
be enhanced when deer and elk are congregated around man-made feed and
water stations.


How soon after CWD exposure do signs of infection appear?

CWD has a long incubation period and typically takes at least 16 months
for an infected animal to show signs of illness. Infected animals do not
show signs of illness until they have been infected for a number of months.

HOWEVER ;

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...

http://vir.sgmjournals.org/cgi/content/full/80/10/2757

Are domestic animals at risk for CWD?

There is no indication to date that CWD is a threat to domestic animals
or livestock other than deer or elk, and there have been no reports of
CWD in dogs or cats.

CWD TRANSMISSION TO DOGS AND CATS HAVE NEVER TAKEN PLACE, so how can
these statement be true?
HOWEVER, other TSE transmit freely to cats and some studies show dogs
are succeptable;

HOUNDS

http://www.priondata.org/data/A_deerdog.html#Hound

CATS

http://www.priondata.org/data/A_deerdog.html#Zoo%20Cats


CWD HAS TRANSMITTED TO CATTLE, SHEEP AND SQUIRREL MONKEY ;

Title: Experimental Transmission of Chronic Wasting Disease (Cwd Mule
Deer) Agent to Cattle by Intracerebral Route Authors

Submitted to: Journal Of Veterinary Diagnostic Investigation
Publication Acceptance Date: January 3, 2005
Publication Date: N/A
Interpretive Summary: This communication reports final observations on
experimental transmission of chronic wasting disease (CWD) from mule
deer to cattle. Thirteen calves were inoculated into the brain with
brain suspension from mule deer naturally affected with CWD. Three other
calves were kept as uninoculated controls. The experiment was terminated
6 years post inoculation (PI). During that time, abnormal prion protein
was demonstrated in the brain and spinal cord of 5 cattle by laboratory
tests. However, consistent clinical signs and microscopic changes were
not seen in any of these cattle. Age related changes were seen in both
inoculated and control cattle. Findings of this study show that only 38%
of the inoculated cattle were positive for CWD agent. Although
inoculation directly into the brain is an unnatural route of exposure,
and is the most severe challenge possible, this experiment shows that
CWD transmission in cattle could have long incubation periods (up to 5
years). This finding suggests that oral exposure of cattle to CWD agent,
a more natural potential route of exposure, would require not only a
much larger dose of inoculum, but also, may not result in amplification
of CWD agent within brain and spinal cord tissues during the normal
lifespan of cattle. It is possible that a second bovine passage of
material (cattle brain infected with CWD) from this study may result in
a larger incidence of affected cattle with a shortened incubation time,
and may produce different clinical and pathological findings. Such a
study is now in progress. Also, experimental inoculations of cattle with
CWD isolates from white-tailed deer and elk are needed to compare
findings with the present study and these studies will be initiated in
the near future. Impact: Results of this study show that although cattle
inoculated directly into the brain with CWD succumb to the disease, the
attack rate was rather small (38%) with this unnatural route of
transmission. It is speculated that the oral route of infection may not
result in replication of the agent during normal lifespan of cattle.

Technical Abstract: This communication reports final observations on
experimental transmission of chronic wasting disease (CWD) from mule
deer to cattle by the intracerebral route. Thirteen calves were
inoculated intracerebrally with brain suspension from mule deer
naturally affected with CWD. Three other calves were kept as
uninoculated controls. The experiment was terminated 6 years post
inoculation (PI). During that time, abnormal prion protein (PrPres) was
demonstrated in the central nervous system (CNS) of 5 cattle by both
immunohistochemistry (IHC) and Western blot (WB). However, microscopic
lesions suggestive of spongiform encephalopathy in the brains of these
PrPres positive animals were subtle in 3 cases and absent in 2 cases.
The 3 uninoculated control cattle and 8 other inoculated animals
euthanized during this time did not have PrPres in their CNS.
Degenerative changes indicative of neuroaxonal dystrophy (NAD) were seen
in dorsal medulla oblongata and appeared to be related to advancing age
in both inoculated and control cattle. Analysis of the gene encoding
bovine PRNP revealed homozygosity for alleles encoding 6 octapeptide
repeats, serine (S) at codon 46 and S at codon 146 in all samples.
Findings of this study show that although PrPres amplification occurred
following direct inoculation into the brain, none of the affected
animals had classic histopathologic lesions of spongiform
encephalopathy. Furthermore, only 38% of the inoculated cattle
demonstrated amplification of PrPres. Although intracerebral inoculation
is an unnatural route of exposure, and is the mo. st severe challenge
possible, this experiment shows that CWD transmission in cattle could
have long incubation periods (up to 5 years). This finding suggests that
oral exposure of cattle to CWD agent, a more natural potential route of
exposure, would require not only a much larger dose of inoculum, but
also, may not result in amplification of PrPres within CNS tissues
during the normal lifespan of cattle.


http://www.ars.usda.gov/research/publications/publications.htm?seq_no_115=166311


Title: Experimental Cross-Species Transmission of Chronic Wasting
Disease (Cwd-Mule Deer) to Domestic Livestock at the National Animal
Disease Center: An Update

snip...


The ovine experiment is 4 years PI and so far 2 sheep (both QQ at codon
171) have been euthanized. Only 1 had clinical signs and histopathologic
lesions of SE that were indistinguishable from sheep scrapie, and the
brain was positive for prion protein. Six remaining sheep (2 QQ and 4 QR
at 171) are apparently healthy. These preliminary findings demonstrate
that although the CWD-mule deer agent can be transmitted to cattle and
sheep by intracerebral inoculation, an obvious neurologic manifestation
of the disease is only seen in the latter species. ...

snip...

http://www.ars.usda.gov/research/publications/publications.htm?SEQ_NO_115=149095


PAGE 25

Transmission Studies

Mule deer transmissions of CWD were by intracerebral inoculation and
compared with natural cases resulted in a more rapidly
progressive clinical disease with repeated episodes of synocopy ending
in coma. One control animal became affected, it is believed through
contamination of inoculam (?saline). Further CWD transmissions were
carried out by Dick Marsh into ferret, mink and squirrel monkey.
Transmission occurred in all of these species with the shortest
incubation period in the ferret.

[hmmm, CWD transmission to squirrel monkey. are humans primates?TSS]

snip...

The occurrence of CWD must be viewed against the context of the
locations in which it occurred. It was an incidental and unwelcome
complication of the respective wildlife research programmes. Despite its
subsequent recognition as a new disease of cervids, therefore justifying
direct investigation, no specific research funding was forthcoming.
The USDA viewed it as a wildlife problem and consequently not their
province!

[figures...TSS]

snip...

VISIT TO USA - DR A E WRATHALL - INFO ON BSE AND SCRAPIE

1. Dr Clark lately of the Scrapie Research Unit, Mission Texas has
successfully transmitted ovine and caprine scrapie to cattle. The
experimental results have not been published but there are plans to do
this. This work was initiated in 1978. A summary of it is:-

better cut this short, you can read full text of part 2 here;

snip...

In Reply to: In Confidence - Perceptions of unconventional slow virus
diseases of animals in the USA - APRIL-MAY 1989 - G A H Wells


http://www.bseinquiry.gov.uk/files/mb/m11b/tab01.pdf

Are prion diseases transmissible to humans


Although there is considerable ongoing research on this issue, there is
no confirmed human neurologic disease linked to CWD at this time. In addition,
there have never been any indications of human illness related to scrapie
in sheep. However, ingestion of cattle infected with BSE overseas appears
to be related to human deaths from a new variant of a previously identified
neurologic disease, Creutzfeldt-Jakob disease (vCJD).

THIS PART OF THIS REPORT IS TOTAL FABRICATION!

FIRST of all, there has never been transmission studies done on man.
FURTHERMORE, CWD does transmit to PRIMATE.
GOING even further;


Conclusions

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.


Acknowledgments

snip...END

http://www.cdc.gov/ncidod/EID/vol10no6/03-1082.htm

snip...

Clearly, it is premature to draw firm conclusions about CWD

passing naturally into humans, cattle and sheep, but the present

results suggest that CWD transmissions to humans would be as

limited by PrP incompatibility as transmissions of BSE or sheep

scrapie to humans. Although there is no evidence that sheep

scrapie has affected humans, it is likely that BSE has caused variant

CJD in 74 people (definite and probable variant CJD cases to

date according to the UK CJD Surveillance Unit). Given the

presumably large number of people exposed to BSE infectivity,

the susceptibility of humans may still be very low compared with

cattle, which would be consistent with the relatively inefficient

conversion of human PrP-sen by PrPBSE. Nonetheless, since

humans have apparently been infected by BSE, it would seem prudent

to take reasonable measures to limit exposure of humans

(as well as sheep and cattle) to CWD infectivity as has been

recommended for other animal TSEs.

snip...

http://www.emboj.org/current.shtml

Aguzzi warns of CWD danger
The TSE family of diseases also includes chronic wasting disease (CWD)
in deer, a condition that has spread in the US in recent years (Nature
416, 569; 2002). Speaking at the Days of Molecular Medicine conference
in La Jolla in March, prion expert Adriano Aguzzi issued a strong
warning against underestimating this form of TSE.
"For more than a decade, the US has by-and-large considered mad cows
to be an exquisitely European problem. The perceived need to protect
US citizens from this alien threat has even prompted the deferral of
blood donors from Europe," he said. "Yet the threat-from-within
posed by CWD needs careful consideration, since the evidence that CWD
is less dangerous to humans than BSE is less-than-complete. Aguzzi
went on to point out that CWD is arguably the most mysterious of all
prion diseases.
"Its horizontal spread among the wild population is exceedingly
efficient, and appears to have reached a prevalence unprecedented even
by BSE in the UK at its peak. The pathogenesis of CWD, therefore,
deserves a vigorous research effort. Europeans also need to think
about this problem, and it would be timely and appropriate to increase
CWD surveillance in Europe too." Aguzzi has secured funding from the
National Institutes of Health to investigate CWD, and the effort will
be lead by Christina Sigurdson in his department at the University of
Zurich. KAREN BIRMINGHAM, LONDON
This quote from Dr. Gambetti is especially significant since he is the
rather cautious TSE researcher under contract with the Centers for Disease
Control to examine the brains of individuals who have died of CJD.
-----------------
Pierluigi Gambetti, director of the National Prion Disease Pathology
Surveillance Center at Case Western Reserve University in Cleveland,
said all deer should be tested for chronic wasting disease before any
processing is done.
"There is no way around it," he said. "Nobody should touch that meat
unless it has been tested."
http://www.ledger-enquirer.com/mld/...ion/3954298.htm


ABOUT SCRAPIE TO HUMANS, more evidence points to the fact
scrapie WILL transmit to humans than evidence that it will not ;


Sheep consumption: a possible source of spongiform encephalopathy in humans.

Davanipour Z, Alter M, Sobel E, Callahan M.

A
fatal spongiform encephalopathy of sheep and goats (scrapie) shares many
characteristics with Creutzfeldt-Jakob disease (CJD), a similar dementing
illness of humans. To investigate the possibility that CJD is acquired by
ingestion of contaminated sheep products, we collected information on production,
slaughtering practices, and marketing of sheep in Pennsylvania. The study
revealed that sheep were usually marketed before central nervous system signs
of scrapie are expected to appear; breeds known to be susceptible to the
disease were the most common breeds raised in the area; sheep were imported
from other states including those with a high frequency of scrapie; use of
veterinary services on the sheep farms investigated and, hence, opportunities
to detect the disease were limited; sheep producers in the area knew little
about scrapie despite the fact that the disease has been reported in the
area, and animal organs including sheep organs were sometimes included in
processed food. Therefore, it was concluded that in Pennsylvania there are
some 'weak links' through which scrapie-infected animals could contaminate
human food, and that consumption of these foods could perhaps account for
spongiform encephalopathy in humans. The weak links observed are probably
not unique to Pennsylvania.

http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=3915057&dopt=Abstract


J Infect Dis 1980 Aug;142(2):205-8


Oral transmission of kuru, Creutzfeldt-Jakob disease, and scrapie to
nonhuman primates.

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.

PMID: 6997404

http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=6997404&dopt=Abstract


Adaptation of the bovine spongiform encephalopathy agent to primates
and comparison with Creutzfeldt- Jakob disease: Implications for
human health

THE findings from Corinne Ida Lasmézas*, [dagger] , Jean-Guy Fournier*,
Virginie Nouvel*,

Hermann Boe*, Domíníque Marcé*, François Lamoury*, Nicolas Kopp [Dagger

] , Jean-Jacques Hauw§, James Ironside¶, Moira Bruce [||] , Dominique

Dormont*, and Jean-Philippe Deslys* et al, that The agent responsible
for French iatrogenic growth hormone-linked CJD taken as a control is
very different from vCJD but is similar to that found in one case of
sporadic CJD and one sheep scrapie isolate;

http://www.pnas.org/cgi/content/full/041490898v1

1: Cent Eur J Public Health 2003 Mar;11(1):19-22

Analysis of unusual accumulation of Creutzfeldt-Jakob disease cases

in Orava and Liptov regions (northern Slovak focus) 1983-2000.

Mad'ar R, Maslenova D, Ranostajova K, Straka S, Baska T.

Institute of Epidemiology, Jessenius Faculty of Medicine, Comenius

University, Sklabinska 26, Martin, 037 53 Slovakia. MADAR@jfmed.uniba.sk


While familial cases of Creutzfeldt-Jakob disease are extremely rare

all over the world, 3 familial clusters were observed between

1983-2000 in a relatively small area situated in the North of

Slovakia. Prevalence of CJD in this area exceeded the overall

prevalence in Slovakia more than 8 times. The majority of CJD

patients admitted consuming sheep brain. Most patients lived in

small secluded villages with rather common familial intermarriage.

CJD affected both sexes equally. All patients were prior to the

disease mentally normal individuals. Shortly after the onset of CJD

their mental status deteriorated remarkably with an average survival

rate of 3.6 months.

PMID: 12690798

http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=12690798&dopt=Abstract


------------------------------------------------------------------------

1: Eur J Epidemiol 1991 Sep;7(5):520-3


"Clusters" of CJD in Slovakia: the first laboratory evidence of scrapie.

Mitrova E, Huncaga S, Hocman G, Nyitrayova O, Tatara M.

Institute of Preventive and Clinical Medicine, Bratislava.

Epidemic-like occurrence of Creutzfeldt-Jakob disease was observed in

1987 in Slovakia (Orava). Search for the cause of CJD focus indicated a

coincidence of genetic and environmental risks in clustering patients.

Since Spongiform Encephalopathies might be transmitted orally, (Bovine

Spongiform Encephalopathy), the possibility of zoonotic source of CJD

cases in Orava was also considered. A deficient knowledge about the

occurrence of scrapie in Slovakia stimulated an examination of sheep

with signs of CNS disorders in two flocks of Valasky breed in Orava. In

one flock, neurohistopathological examination revealed in sheep brains

lesions characteristic for scrapie. Frozen brain tissue of these animals

were used for the detection of scrapie associated fibrils. They were

found in 2 animals from the same flock. This is the first laboratory

confirmation of scrapie in Czecho-Slovakia. The possible epidemiological

and economical implications are emphasized.

http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=1761109&dopt=Abstract


Are there health risks for hunters in handling deer or elk?

There is no evidence to date that hunters have a risk of acquiring CWD.
Depending on how an animal is handled, there may be a risk of other diseases
including rabies. Hunters should observe normal precautions around any animals,
such as avoiding sick or strange-acting animals. They must report to their
local health department any potential rabies exposures such as an animal
bite or scratch, or contact between a person's eyes, nose, or mouth (mucous
membranes) or fresh open wound with the animal's saliva, brain, or other
nervous tissue. ...

http://www.health.state.ny.us/nysdoh/zoonoses/cwd.htm

MIXED SIGNALS


Are there any precautions for handling, processing, or eating meat from
deer or elk?

To minimize the risk of transmission of any infectious diseases when
handling or processing animals, the following precautions are recommended:

· Deer or elk that are observed to be ill, or found dead, should not
be handled and should not be eaten.

· Wear rubber gloves when field dressing carcasses.

· Wash instruments and any parts of the body exposed to animal
tissues, blood, urine, etc. thoroughly with soap and water.

· Minimize handling brain or spinal tissues/fluids and wash hands
thoroughly with soap and water afterward if such handling occurred. If
these nervous tissues or fluids get into a fresh open break in a
person's skin or the eyes, mouth, or nose, contact the local health
department to evaluate possible rabies exposure and need for testing the
animal for other diseases.

· Request if possible that individual animals are processed
individually, without meat from other animals being added together.

· Although no CWD risk to humans has been identified from consumption
of organ meat, in general consumption of organ meat (including brain,
spinal cord, and other nervous tissue, spleen, pancreas, eyes, tonsils,
lymph nodes) may pose a greater risk of infection with a number of
diseases. Boning out meat, including removal of fat, connective tissue,
and lymph nodes, should be done with animals from states with confirmed
CWD.

· Animals testing positive for CWD should not be distributed or
donated for human consumption.

· For more information about handling, processing, or eating meat
from deer or elk in other states, contact those state agriculture,
wildlife, and health agencies.

Are there any risks from deer waste or products?

Although there is no indication of human infection due to contact with
deer waste or products related to CWD-infected deer or elk, the
following general disease control precautions are recommended:

· Avoid contact with animal bodily waste material, and clean up
animal waste from areas frequented by children.

· If there is skin contact with animal waste, wash the area with soap
and water immediately.

· Deer scent products should be formulated with methods to avoid
concerns about CWD contamination.

Snip..

http://www.health.state.ny.us/nysdoh/zoonoses/cwd.htm

OR


> Observer-Dispatch
>
> VERONA - The white-tailed deer recently diagnosed with chronic wasting
> disease was one of the deer donated to the Verona Fire Department and
> served at its Annual Sportsmen's Feast on Sunday, March 13, an Oneida
> County Health Department spokesman said today.
>
> People who consumed the venison need not worry about contracting the
> disease, spokesman Ken Fanelli said.
>
> "There's no indication whatsoever that the disease has been linked to
> human illness of any kind," Fanelli.
>
> The deer was donated before the health department knew it had the
> disease, according to the health department.

http://www.uticaod.com/news/updates/update2005-04-04.htm


Don't touch that animal !

BUT, if it was served at Verona, No problem at all, Don't worry, be happy?

right... talk about 'mixed signals' ...TSS


What should be done if someone sees a sick deer/elk?

Because a sick deer or elk could have rabies, if there has been human
contact of concern (see above) the animal must be reported to the local
health department. After the animal has been humanely euthanized, the
local health department will send the head to the New York State Health
Department's Rabies Laboratory for rabies testing. Animals that are
negative for rabies will be submitted for subsequent CWD testing. If
there has been no human contact, the sick animal should be reported to
the nearest New York State Department of Environmental Conservation
office for humane euthanasia and CWD testing.


Are there any precautions for handling, processing, or eating meat
from deer or elk?

To minimize the risk of transmission of any infectious diseases when
handling or processing animals, the following precautions are recommended:

* Deer or elk that are observed to be ill, or found dead, should not
be handled and should not be eaten.
* Wear rubber gloves when field dressing carcasses.
* Wash instruments and any parts of the body exposed to animal
tissues, blood, urine, etc. thoroughly with soap and water.
* Minimize handling brain or spinal tissues/fluids and wash hands
thoroughly with soap and water afterward if such handling
occurred. If these nervous tissues or fluids get into a fresh open
break in a person's skin or the eyes, mouth, or nose, contact the
local health department to evaluate possible rabies exposure and
need for testing the animal for other diseases.
* Request if possible that individual animals are processed
individually, without meat from other animals being added together.
* Although no CWD risk to humans has been identified from
consumption of organ meat, in general consumption of organ meat
(including brain, spinal cord, and other nervous tissue, spleen,
pancreas, eyes, tonsils, lymph nodes) may pose a greater risk of
infection with a number of diseases. Boning out meat, including
removal of fat, connective tissue, and lymph nodes, should be done
with animals from states with confirmed CWD.
* Animals testing positive for CWD should not be distributed or
donated for human consumption.
* For more information about handling, processing, or eating meat
from deer or elk in other states, contact those state agriculture,
wildlife, and health agencies.
*


Are there any risks from deer waste or products?

Although there is no indication of human infection due to contact with
deer waste or products related to CWD-infected deer or elk, the
following general disease control precautions are recommended:

* Avoid contact with animal bodily waste material, and clean up
animal waste from areas frequented by children.
* If there is skin contact with animal waste, wash the area with
soap and water immediately.
* Deer scent products should be formulated with methods to avoid
concerns about CWD contamination.


PLEASE SEE FURTHER DATA BELOW ...TSS


Environmental Sources of Prion Transmission in Mule Deer

Michael W. Miller,*Comments
Elizabeth S.
Williams, N. Thompson Hobbs,! and Lisa L. Wolfe*
*Colorado Division of Wildlife, Fort Collins, Colorado, USA; University
of Wyoming, Laramie, Wyoming, USA; and !Colorado State University, Fort
Collins, Colorado, USA

Suggested citation for this article: Miller MW, Williams ES, Hobbs
NT, Wolfe LL. Environmental sources of prion transmission in mule
deer. Emerg Infect Dis [serial on the Internet]. 2004 Jun [date
cited]. Available from:
http://www.cdc.gov/ncidod/EID/vol10no6/04-0010.htm

------------------------------------------------------------------------

Whether transmission of the chronic wasting disease (CWD) prion
among cervids requires direct interaction with infected animals has
been unclear. We report that CWD can be transmitted to susceptible
animals indirectly, from environments contaminated by excreta or
decomposed carcasses. Under experimental conditions, mule deer
(Odocoileus hemionus) became infected in two of three paddocks
containing naturally infected deer, in two of three paddocks where
infected deer carcasses had decomposed in situ ?1.8 years earlier,
and in one of three paddocks where infected deer had last resided
2.2 years earlier. Indirect transmission and environmental
persistence of infectious prions will complicate efforts to control
CWD and perhaps other animal prion diseases.

FULL TEXT ;

http://www.cdc.gov/ncidod/eid/vol10no6/04-0010.htm


How is CWD diagnosed?

While apparently healthy animals might be infected, eventually infected
animals will develop signs of illness. Definitive diagnosis for the
disease currently requires laboratory testing of the brain and/or lymph
nodes.


Can a specific deer or elk be tested?

There is ongoing CWD surveillance in New York State, but a
fee-for-service program of testing individual animals is not currently
available. Precautions provided above for handling and consumption
should be followed.

PLEASE SEE FURTHER DATA BELOW ...TSS

CWD Review / Dr Debra Bourne / October 2004 / For SEAC / Page 26 of 66
Changes in distribution of PrP and lesions with time during infection
113. Data from studies in naturally and experimentally infected
Odocoileus hemionus, and
naturally infected Cervus elaphus nelsoni, suggest that the
parasympathetic region of the
vagus nerve in the medulla may be the earliest site of PrPCWD
accumulation in the brain in the
natural hosts of CWD (Peters et al, 2000; Williams & Miller, 2000;
Sigurdson et al., 2001;
Miller & Williams, 2002; Spraker et al., 2002b; Spraker et al., 2004).
114. When mule deer fawns of about five months old were orally
inoculated, PrPCWD was
detected in cervical lymph nodes at three months post inoculation.
PrPCWD was widespread in
lymphoid tissues by six months post inoculation, at which time PrPCWD
was detected in the
CNS for the first time, in the medulla oblongata, at the lateral aspect
of the parasympathetic
vagal nucleus. Lesions of spongiform encephalopathy did not develop at
this site until at least
15 or 16 months post inoculation, at which time early clinical signs
were present (Williams &
Miller, 2000; Williams & Miller, 2002).
115. One study, based on histopathology and detection of PrPCWD by
immunohistochemistry (using monoclonal antibody F89/160.1.5) in the
brain and palatine
tonsil of 35 hunter-killed free-living mule deer with natural CWD,
suggested four categories
of infection (Spraker et al., 2002b):
Category 1: detectable PrPCWD in the tonsil but no evidence of spongiform
encephalopathy in the brain and no detectable PrPCWD in the brain by IHC;
Category 2: positive by IHC in the tonsil and the dorsal motor nucleus
of the vagus
nerve (DMNV), with or without histological lesions of spongiform
encephalopathy at
this site;
Category 3: positive by IHC in the tonsil, positive by IHC with
histological lesions of
spongiform encephalopathy in the myelencephalon and PrPCWD positive by
IHC in the
hypothalamus, but without lesions of spongiform encephalopathy in this
region;
Category 4: positive by IHC in the tonsil, with the presence of PrPCWD
detectable by
IHC throughout the brain and lesions of spongiform encephalopathy
throughout the
brain.
116. It was suggested that these categories may represent stages in the
pathogenesis of
CWD, with category one animals having early lymphoid tissue localisation
of PrPCWD, while
categories two to four representing the progression of spread through
the CNS (Spraker et al.,
2002b).
117. A study of 226 naturally infected Rocky Mountain elk similarly
demonstrated that PrP
could be detected in the lower half of the dorsal nucleus of the vagus
nerve without any
staining of other regions of the myelencephalon at the obex, or could be
found in this nucleus
plus other surrounding nuclei. Histopathological lesions were detected
only in the sections
from brains with relatively heavy PrPCWD and widespread deposition
(Spraker et al., 2004).
Variations between species
118. The progression of infection in Cervus elaphus nelsoni differs
somewhat from that in
Odocoileus spp. deer (Williams et al., 2002). As with deer, the
parasympathetic region of the
dorsal nucleus of the vagal nerve appears to be the first brain region
to become infected; a
study of more than 10,000 elk found that in some individuals PrPCWD was
detectable only at
this site, not elsewhere in the brain (Spraker et al., 2004). However,
lymphoid tissue
involvement, as indicated by detection of PrPCWD, is more variable than
in Odocoileus spp.
CWD Review / Dr Debra Bourne / October 2004 / For SEAC / Page 27 of 66
deer. In a study involving testing of more than 10,000 elk, in which 226
animals were CWDpositive,
155 (68.6%) had PrPCWD deposits in both brainstem and lymphoid tissue,
43 animals
(19%) were CWD positive only in lymphoid tissue. Within the lymphoid
tissues, some
animals had staining only in the retropharyngeal lymph node, some only
in the tonsil and
others in both lymphoid tissues; variation in whether and which lymphoid
tissue was PrPCWD -
positive occurred for all recorded levels of brain infection (Spraker et
al., 2004).
Individual variation
119. Studies on both naturally infected Odocoileus spp. deer and individuals
experimentally infected by oral inoculation indicate that lymphoid
tissues become PrPCWD
positive before detectable involvement of the CNS (Sigurdson et al.,
1999; Spraker et al.,
2002b; Miller & Williams, 2002). However there may be some natural
variation in
pathogenesis; occasional individuals are detected in which the obex is
positive for PrPCWD by
IHC but tonsil and/or retropharyngeal lymph node are negative (Spraker
et al., 2002a; Miller
& Williams, 2002).
6) DIAGNOSIS
120. Clinical signs (loss of body condition and behavioural changes) are
commonly used
for detection of CWD in both captive and free-ranging cervids (Miller &
Williams, 2004),
however these signs are not pathognomonic and, as noted in paragraphs
78-81, the
presentation of clinical cases may vary. Additionally, due to the
progressive nature of the
disease, casual inspection, even by experienced personnel, may fail to
detect individuals with
clinical CWD (Miller & Williams, 2004). A wide variety of diseases which
cause emaciation
and/or nervous signs must be included as differential diagnoses for
cervids with CWD
(Williams, Kirkwood & Miller, 2001; Williams & Miller, 2002).
121. Definitive diagnosis requires histopathological examination of the
brain for
spongiform lesions (Williams & Young 1980; Williams & Young, 1982;
Williams & Young
1992, Williams & Young 1993) and/or immunohistochemical detection of PrPCWD
accumulation in the lymph nodes and/or brain (Williams & Young 1992;
Miller et al., 2000;
Peters et al., 2000, Spraker et al., 2002b; Williams & Miller, 2002).
122. Several tests are now available for diagnosis of CWD in cervids.
Tests should be
validated for the tissue and species on which they should be used;
additional factors which are
considered when choosing diagnostic tests for large-scale CWD
surveillance include the time
required to process the samples, the quantity of samples which can be
processed and the
condition (e.g. fresh, decomposed) of the tissue to be tested (Samuel et
al., 2003).
123. It should be noted that whatever the sensitivity of the tests used,
because of
uncertainties regarding incubation time and the interval from natural
infection to the
appearance of detectable PrPCWD in tested tissues, an individual cervid
in which PrPCWD is not
detected cannot be guaranteed not to be infected with CWD (Wild et al.,
2002; Samuel et al.,
2003; Spraker et al., 2004).
Histopathology
124. Initially, the presence of typical lesions of spongiform encephalopathy
(microcavitation of the grey matter, neuronal intracytoplasmic vacuoles,
loss and
degeneration of neurons, astrocytosis) in the olfactory tubercle and
cortex, hypothalamus and
the parasympathetic vagal nucleus were recognised as sufficiently
consistent that
histopathological examination of these areas could be used for
diagnosis. It was noted that in
healthy (CWD-negative) individuals a few intraneuronal vacuoles may be
found in the red
nucleus, but not in other sites (Williams & Young, 1992; Williams &
Young, 1993).
CWD Review / Dr Debra Bourne / October 2004 / For SEAC / Page 28 of 66
125. For several years it has been recognised that the dorsal motor
nucleus of the vagus
(DMNV), in the dorsal port of the medulla oblongata at the obex, is the
earliest and most
consistent site in the brain at which histopathological lesions of CWD
can be detected in all
three known natural hosts of CWD (Cervus elaphus nelsoni, Odocoileus
hemionus and
Odocoileus virginianus) (Peters et al., 2000; Miller et al., 2000,
Williams & Miller, 2000;
Spraker et al., 2002b; Miller & Williams, 2004).
126. Disadvantages of histopathology for diagnosis include the
requirements for very fresh
tissues (no autolysis), which are not always available from field
specimens (Spraker et al.,
2002a; Kahn et al., 2004) and the fact that histological lesions do not
develop until quite late
in the course of infection (Miller & Williams, 2002; Spraker, 2003) (see
paragraphs 114-116).
Immunohistochemistry
127. Immunohistochemical (IHC) staining for PrPCWD has been used to
confirm diagnosis
of CWD for some time (Williams & Young, 1992). PrPCWD can be detected by
IHC in brain
tissue and/or lymphoid tissue in the absence of histopathological
spongiform lesions
(Sigurdson et al., 1999; Peters et al., 2000). IHC of the
parasympathetic vagal nucleus in the
dorsal medulla at the obex is sensitive and specific for CWD diagnosis
in Odocoileus spp.
deer and in Cervus elaphus nelsoni (Miller et al., 2000; Miller &
Williams, 2002; Miller &
Williams, 2004). IHC has high sensitivity and high specificity
(Creekmore, 2003; Bollinger et
al., 2004). IHC, particularly using monoclonal antibody F99/97.6.1, is
still considered by
most working in the CWD field to be the gold standard (Creekmore,
2003; Samuel et al.,
2003; Hall, 2004; Kahn et al., 2004); it allows precise anatomical
considerations of PrP
deposition in addition to the simple presence of PrPCWD (Creekmore,
2003), and is considered
not to produce any false positive reactions (Hall, 2004).
128. Monoclonal antibodies used for IHC do not in themselves
differentiate between the
normal cellular PrPC and the disease-associated form of PrP. Specificity
for the diseaseassociated
form therefore requires appropriate pretreatment of the tissue to
denature PrPC
(Spraker et al., 2002a; Williams & Miller, 2002).
129. One advantage of IHC over histopathological examination using
standard stains such
as haematoxylin and eosin is that it can be used on tissue which is
somewhat autolysed
(Spraker et al., 2002a).
130. Several monoclonal antibodies have been evaluated for use in CWD
diagnosis.
F99/97.6.1 (ORourke et al., 2000) has been proven as the most reliable
for use on brain,
retropharyngeal lymph node or tonsil and is the monoclonal antibody used
most commonly
for IHC in the USA and Canada (Miller & Williams, 2000; Spraker et al.,
2002a; Samuel et
al., 2003; Spraker, 2003; Miller & Williams, 2004). F99/97.6.1 reacts
with a conserved
epitope, residues QYQRES) found on the prion protein of mule deer,
white-tailed deer and
Rocky Mountain elk as well as sheep, cattle, mink and various other
species (ORourke et al.,
2000; Spraker et al., 2002a; Spraker, 2003). This antibody was validated
on brain and tonsil
samples from 100 CWD-positive and 300 CWD-negative mule deer and was
found to be
excellent for detection, including for use on fresh or frozen tissues
and on tissues which were
mildly to moderately autolysed (Spraker et al., 2002a). It was noted
that Mab F89/160.1.5
was also highly specific for deer brain but gave some false-positive
reactions in deer tonsils,
probably due to detection of the epitope on PrPC (Spraker et al., 2002a).
131. Lymphoid tissues, specifically the tonsils and the retropharyngeal
lymph nodes, can
also be used for diagnosis of CWD using IHC in Odocoileus spp. deer
(Spraker et al., 2002a;
CWD Review / Dr Debra Bourne / October 2004 / For SEAC / Page 29 of 66
Miller & Williams, 2002; Miller & Williams, 2004). These tissues are
easily collected from
the heads of hunter-harvested deer (Williams et al., 2002; Miller &
Williams, 2004).
132. In most Odocoileus spp. deer, these tissues are involved relatively
early in infection
(Sigurdson et al., 1999; Spraker et al., 2002b; Miller & Williams,
2002), therefore IHC of
tonsil and/or retropharyngeal lymph node alone (i.e., without also
testing the brain stem at the
obex), may be sufficient for epidemiological surveys of prevalence in
wild deer (Spraker et
al., 2002a; Miller & Williams, 2002). However, due to variations between
species, and
individual variation, it is recommended that to maximise detection of
CWD infected
individuals both the obex and cranial lymphoid tissues should be tested
for the presence of
PrPCWD (Williams et al., 2002; Miller & Williams, 2004). Further
information on these
differences is provided in paragraphs 118-119. Additionally it must be
remembered that
failure to detect PrPCWD in these tissues does not totally rule out the
possibility that the
individual is infected; a negative result may occur early in the course
of infection (Sigurdson
et al., 1999; Miller & Williams, 2002; Wild et al., 2002; Samuel et al.,
2003).
133. In Odocoileus spp. deer, IHC can also be used to detect PrPCWD in
biopsy specimens
from the tonsils of live individuals. This procedure requires the deer
to be anaesthetised, so is
not suitable for large-scale surveillance operations, however it may be
useful in situations
where harvest-based surveillance is not practical and where intensive
management is feasible
(e.g. deer resident in urban areas, or in national parks) (Wild et al.,
2002; Wolfe et al., 2002;
Wolfe, Miller & Williams, 2004). Diagnosis from tonsillar biopsies is
not applicable to
Cervus elaphus nelsoni because of the differences in PrPCWD accumulation
in lymphoid
tissues in this species (Wild et al., 2002; Spraker, 2003; Spraker et
al., 2004). Sampling of
conjunctival lymphoid tissue, as used in sheep (ORourke et al., 1998b;
ORourke et al.,
2000), is not applicable to deer because of the sparsity of this tissue
in deer (Williams &
Miller, 2002; Kahn et al., 2004).
134. Potential disadvantages of immunohistochemistry, particularly for
large-scale
surveillance programmes, are that it takes time (including the delay in
preparing tissues prior
to reading the slide), requires specialised skills, it is subjective (as
opposed to tests utilising an
objective numerical cut-off point to separate negative from positive
samples), and it may
potentially be influenced by prior knowledge of the case from which the
sample was taken
(including the results of other tests carried out on the sample) (Salman
& Gardner, 2004).
135. Where the new rapid tests are used for surveillance, IHC is
recommended as a
secondary test to confirm positives detected by the initial screening
test and to reject false
positives (Samuel et al., 2003; Bollinger et al., 2004).
Electron microscopy
136. Negative stain electron microscopy to detect scrapie-associated
fibrils (SAF) (see
paragraph 104) can be used as a supplemental diagnostic test for CWD in
mule deer, whitetailed
deer and elk (Williams & Young, 1992; Spraker et al., 1997; Williams &
Miller, 2002).
SAF may be found in the spleen as well as in the brain (Spraker et al.,
1997; Williams &
Miller, 2002). As with immunohistochemistry, SAF can be demonstrated
even in autolysed
tissues (Williams & Young, 1992).
Other tests
137. New rapid tests for CWD (ELISA and Western blot) are now being used.
Commercially available tests are based on those developed for the
detection of BSE. These
tests use unfixed tissues (Bollinger et al., 2004), which removes a
delay in time taken from
sampling to test results. As with IHC the sensitivity of such tests
depends on the tissue(s)
CWD Review / Dr Debra Bourne / October 2004 / For SEAC / Page 30 of 66
being tested. In general, these tests have a high sensitivity but a
lower specificity, leading to
some false-positive results (Bollinger, 2004).
ELISA
138. ELISA-based test kits have the advantage that they allow rapid
testing of large
numbers of samples (Creekmore, 2003). ELISA-based test kits from three
different
companies have been approved by USDA Center for Veterinary Biologicals
for use as
screening tests for the detection of CWD in free-ranging cervid
populations, but none has yet
been approved for use for testing of farmed cervids in regulatory
programmes. One test kit,
from VMRD, has since been withdrawn from the market.
139. A Bio-Rad test kit was approved by APHIS for use in mule deer
(Odocoileus
hemionus), white tailed deer (Odocoileus virginianus - White-tailed
deer) and elk Cervus
elaphus nelsoni - Rocky Mountain Elk by testing specific lymph nodes
(APHIS, 2002, B.L.
Morrison, pers. comm., 2003). According to the manufacturer, the Bio-Rad
test combines a
purification protocol for increased sensitivity with rapid detection by
ELISA. Results are
available in 4 hours. Two specific monoclonal antibodies are used in
the test (Bio-Rad,
2004). The Bio-Rad ELISA CWD antigen test kit was validated using 4,175
retropharyngeal
lymph node or obex samples, with the results of the ELISA being compared
with
immunohistochemistry (IHC) findings (IHC-positive individuals being
taken as being CWDinfected
and IHC-negative individuals being taken as uninfected) (Hibler et al.,
2003). The
relative specificity of the ELISA was 99.9-100% and the sensitivity was
98.3-100% for
retropharyngeal lymph node samples and 92.1-93.3% sensitive for obex
samples. Overall
there was agreement for at least 97.6% of lymph node and at least 95.7%
of obex samples
where values could be calculated. ELISA optical density (OD) values were
at least 46 times
higher for IHC-positive than for IHC-negative samples. Discrepancies
between IHC and
ELISA results were found only for early-stage CWD cases. In the
field-application stage,
20,875 retropharyngeal lymph node samples were screened with the ELISA.
The 155 of 8,877
mule deer, 33 of 11,731 elk and nine of 267 white-tailed deer with ELISA
OD values greater
than 0.1 (value based on data from the validation phase of the study)
were classified as
CWD-suspect and evaluated by IHC; 143 of155 mule deer, 29 of /33 elk
and all nine whitetailed
deer were IHC-positive and mean ELISA OD values were comparable to those
measured during the validation stage. It was considered that the Bio-Rad
ELISA was an
excellent rapid test for screening large numbers of samples in surveys
designed to detect
CWD infection in deer and elk populations. From the study an OD cut-off
of greater than or
equal to 0.1 was recommended for screening retropharyngeal lymph node
tissues of deer and
elk in large-scale surveys to minimise the risk of false-negative
results, giving a screening test
with about 99.6% sensitivity, with a follow-up of IHC, carried out by a
reliable experienced
laboratory, to remain as the final determination test for CWD on
ELISA-positive samples
(Hibler et al., 2003). A second Bio-Rad ELISA-based test (TeSeE® was
approved by USDA
during 2003 (Chronic Wasting Disease Alliance, 2003).
140. The HerdChek® test kit from IDEXX also has been approved by USDA
(IDEXX,
2004a). The HerdChek test uses homogenised lymph node tissue. The
process takes a total of
three-and-a-half hours and offers 98.8% sensitivity and 100%
specificity, validated through
IHC confirmation testing. Sensitivity was 98.8% (80 of 81 samples) and
specificity 100%
(248 samples) as confirmed by IHC on samples from Odocoileus virginianus
- White-tailed
deer (IDEXX, 2004b; IDEXX, 2004c).
Immunoblotting
141. Immunoblotting techniques are carried out on fresh or frozen, but
not fixed, tissues
(Stack, Keyes & Scott, 1996).
CWD Review / Dr Debra Bourne / October 2004 / For SEAC / Page 31 of 66
142. Western blot assays may be used for detection of PrPCWD in the
brains of both
clinically affected and (presumably) preclinical cervids (Laplanche et
al., 1999). In a study on
more than 10,000 Cervus elaphus nelsoni, tissue for Western blotting was
taken from the
medulla caudal to the section used for IHC. No samples which were
negative by IHC were
positive by Western blot. While all samples from 46 elk with heavy
PrPCWD deposits in the
dorsal nucleus of the vagus and spreading to surrounding nuclei were
positive on the Western
blot, only 16 of 30 samples from elk with only moderate PrPCWD deposits
restricted to the
dorsal nucleus of the vagus nerve and the solitary tract, and only five
of 27 samples from elk
with only scant PrPCWD deposits restricted to the dorsal nucleus of the
vagus nerve and the
nucleus of the solitary tract, were positive. The discrepancies were
probably due to lack of the
dorsal motor nucleus of the vagus nerve within the tissue sample used
for the Western blot
assay (Spraker et al., 2004). Western blotting was also carried out on
lymphoid (tonsil and
retropharyngeal lymph node) tissues; in 33 elk this test detected PrPCWD
deposits in the brain
and lymphoid tissue, in three it detected PrPCWD in the brain but not in
lymphoid tissue, and in
two it detected PrPCWD in lymphoid tissue but not in the brain (Spraker
et al., 2004).
143. A dot-blot assay using monoclonal antibody F99/97.6.1 has been
described using 150
mg of frozen tonsillar tissue in a 10% (weight/volume) detergent lysate
without either
purification or enrichment steps in the preparation. The assay detected
PrPCWD in 49 of 50
tonsils which were positive by IHC. Poor trimming (i.e. lack of relevant
tonsillar tissue in the
tissue prepared for dot-blot) was considered the most likely reason for
the single discrepant
result; the IHC was carried out on the central portion of the original
sample while the dot-blot
was carried out on one of the two flanking pieces of tissue.
Quantification was possible from
48 of the samples. This was based on densiometry readings of each blot,
extrapolated against
a standard curve for each filter based on known quantities of ovine
PrPSc sharing the
conserved epitope for Mab F99/97.61, with mean density of the signal for
each calibrator
plotted against concentration for linear regression analysis. Tonsillar
PrPCWD concentrations
were found to vary from 34 to 1,188 ng per 0.5 mg of initial wet weight
of tissue (ORourke
et al., 2003).
Conformation-dependent immunoassay (CDI)
144. The conformation-dependent immunoassay (CDI) has been tested for
the detection
of CWD prions and found to have a sensitivity comparable with transgenic
mouse bioassays
for BSE (Safar et al., 2002). Using this test, which depends on the
antibody binding affinity to
PrPSc conformers and is PrPSc strain-specific, samples from Odocoileus
virginianus  whitetailed
deer and Odocoileus hemionus  mule deer were found to be similar to one
another.
However, samples from Cervus elaphus nelsoni  Rocky Mountain elk could
be differentiated
from those of the other two species. The finding was considered to
indicate a difference in
conformation between PrPSc from Odocoileus spp. deer and that from the
elk, but it was not
possible to say whether this indicated a prion strain difference (Safar
et al., 2002).
Limitations of rapid tests
145. In a few cases, IHC may be more sensitive than other tests by
virtue of detection in
specimens with only occasional single-cell staining. In most samples IHC
shows
immunostaining of more than half the lymphoid follicles within a
lymphoid tissue biopsy
specimen, and in such tissues the rapid tests should also detect the
PrPCWD (ORourke et al.,
2003).
146. An important limitation of the rapid tests is a lack of certainty
regarding the precise
identity of the tissue being tested. While absence of correct tissue may
also affect results of
testing by IHC, the architecture of the tissue is preserved for IHC
therefore it is possible to
identify whether or not the required area is present in the sample. It
has been noted that
standardisation of both tissue collection and tissue trimming techniques
are essential for
accuracy of high-throughput tests (Hibler et al., 2003; ORourke et al.,
2003). A study using
the CDI noted that measured PrPSc concentrations within sections of the
obex region in cattle
could vary markedly (eight-fold) depending on exactly which part of the
obex was sampled.
This finding confirms the importance of consistency of samples used in
the test (Safar et al.,
2002).
147. While rapid tests are often used for screening of large numbers of
samples in
surveillance programmes, positive results are confirmed using IHC. This
is particularly
important for confirming the presence of CWD in a geographic location in
which it has not
previously been detected (Samuel et al., 2003).
Choice of tissues for testing
148. As with IHC, testing of lymph nodes or tonsils will not detect
individuals very early in
the course of infection (Sigurdson et al., 1999; Miller & Williams,
2002; Wild et al., 2002).
Testing these tissues only, not obex also, will fail to detect those
individuals in which PrPCWD
has not accumulated in lymphoid tissue, but is present in the brain at
the obex. This situation
is rare for Odocoileus spp. deer but relatively common in Cervus elaphus
nelson (Miller &
Williams, 2002; Wild et al., 2002; Spraker, 2003; Spraker et al., 2004).

http://www.seac.gov.uk/papers/cwdiseaseannex1.pdf


111
Project Title: Bovine Spongiform Encephalopathy and Other Transmissible
Spongiform Encephalopathies
CRIS Number: 3625-32000-066-00D
Scientists: Hamir, A., Kunkle, R., Richt, J., Kehrli, M., Vacant, Vacant
Location: Ames, IA, National Animal Disease Center, Virus and Prion
Diseases of Livestock
Contact: Kehrli, M., Phone: (515) 663-7254, Fax: (515) 663-7458
mkehrli@nadc.ars.usda.gov
PROJECT OBJECTIVES:
This project was expanded in January 2002 from the original TSE
project that investigated scrapie. Today the
project focuses on investigations of various Transmissible
Spongiform Encephalopathies (TSE), which are
fatal degenerative diseases of the central nervous system that can
affect several animal species, including
humans. The causal agent is believed to be a natural tissue protein,
the prion protein, that has assumed an
unnatural form. Because the altered protein is resistant to enzyme
degradation, it accumulates in nervous tissue
and the resulting dysfunction ultimately leads to death. The
specific TSEs being investigated in this project are
scrapie in sheep, chronic wasting disease (CWD) in deer and elk, and
transmissible mink encephalopathy
(TME) in mink. The major concern about these diseases is that
another TSE, bovine spongiform
encephalopathy (BSE), has been shown to cross the species barrier to
cause a unique TSE in human beings.
Although there has not been a similar demonstration that scrapie,
CWD or TME could present any risk to
human health, the BSE experience has raised many questions about the
potential hazard these TSEs present for
transmission to other animal species, especially domesticated
livestock and wildlife. The major objectives are
to assess transmissibility of the TSEs that affect livestock and
wildlife species, to develop methods for
differentiation of TSE strains, and to determine the pathobiology of
these diseases in the natural host and after
cross-species transmission. Results of animal inoculation studies
are then compared to results obtained with a
variety of laboratory procedures to determine if they can be used as
predictive models for future risk
assessments. These studies also provide information about the
clinical and pathological disease characteristics
that can be expected if a TSE crosses the species barrier, thus
enabling animal health specialists to recognize
such situations should they occur. Additional transmission studies
in the natural host will focus on determining
the modes of transmission and disease development in scrapie and CWD
so that appropriate intervention
strategies can be devised that will control the spread of these
diseases. Studies, in collaboration with APHIS,
are underway to determine the role of genetics in the susceptibility
of elk to CWD. The scrapie, CWD and
TME agents will be used in experiments to further assess the risk
that these TSEs might pose to cattle, sheep,
and swine. These experiments will also provide information and
tissues that can be used to evaluate the
effectiveness of current diagnostic protocols for animal TSEs.
Cooperative research with the United Kingdom
includes strain typing of CWD isolated from cases in the U.S.A.
utilizing the mouse bioassay, use of
recombinant prion proteins to develop or improve existing in vitro
conversion strain-typing assays, use of
immunohistochemistry to improve the standard pathology-oriented
mouse strain-typing bioassay, and
development of in vitro assays to predict infective titer of tissues
derived from TSE-affected animals. Sheep
scrapie studies are underway to determine influences of strain
source and host genetics in disease progression.
Current experiments are in progress to determine transmissibility of
CWD from mule deer into cattle and
112
sheep. White-tailed deer have been inoculated with CWD from elk,
mule deer and white-tailed deer to
determine if there are strain differences in the agent that depend
on host origin.
OVERALL PROJECT ACCOMPLISHMENTS:
Scientists on this project have demonstrated the transmissibility of
scrapie to cattle by intracerebral inoculation
and that the pathology of scrapie-affected cattle differed from BSE;
importantly, cattle were shown to be
resistant to challenge with scrapie by the oral route. Another
significant accomplishment was the development
and ongoing verification of the immunohistochemistry (IHC) test used
by APHIS in the BSE surveillance
program. A recent contribution of this project was the development
of a method to conduct genotyping of the
sheep prion gene using formalin-fixed and paraffin-embedded tissues
as the DNA source material. Most
recently, several of our research capabilities were utilized when
project scientists contributed critical research
in support of the 2003 BSE diagnosis. Western blot analyses and
prion allele sequencing from the index case
verified the accuracy of the APHIS IHC test and the species origin
of the tissues as bovine. Current studies of
CWD transmissibility to cattle indicate a relative resistance to
infection and a pathology profile which differs
from BSE. Another significant accomplishment was the demonstration
that abnormal prions are not detectable
by IHC in striated muscle tissues from animals experimentally
inoculated with agents of TSEs. The current
project has also demonstrated the utility of raccoons as a model for
strain-typing TSEs; raccoons are very
susceptible to TME, moderately so to scrapie, and resistant to CWD.
In FY 2003 a mouse facility, dedicated
for TSE strain typing of U.S. TSE isolates was built. This is a
critical advance in our research capabilities to
conduct the gold standard mouse bioassay for the differentiation of
TSE strains (strain-typing). The mouse
bioassay uses 4 inbred mouse strains with different prion protein
genotypes. The new facility is essential for
rearing these mice and is now operational. Mice from different PrP
genotypes are being raised for future
inoculation with defined U.S. scrapie and CWD isolates.
Concurrently, in vitro strain typing efforts which rely
on biochemical analysis of the pathological form of the prion
protein (PrPd) were started because the animal
bioassay is relatively slow and expensive. This methodology involves
determination of molecular mass and
glycoform profile by Western Blot analysis. Preliminary results
indicate CWD isolates from mule deer and
white-tailed deer differ in molecular size when compared to CWD
isolates from elk. Recently, completed
work has determined that scrapie can be transmitted to elk and the
resulting disease is indistinguishable from
CWD in that species.
IMPACT:
Ongoing research verification of the IHC test used by APHIS has
ensured the sensitivity and specificity of the
test for BSE. Research support of the 2003 BSE case provided APHIS
diagnostic pathologists with research
verification of the IHC results and assurance the brain tissue was
accurately identified as bovine in origin. A
critical question for consumers is whether abnormal prion protein is
present in meat, our research has shown
that abnormal prion protein is not detectable by IHC in skeletal
muscle tissues of animals experimentally
inoculated with scrapie, CWD or TME. The demonstration that cattle
and sheep are relatively resistant to
experimental inoculation with CWD suggests that transmission of CWD
to cattle or sheep in nature is not
likely to occur easily. In addition, raccoons were shown to be a
potential model for in vivo differentiation of
the 3 animal prion diseases found in the United States (scrapie,
CWD, and TME).
TECHNOLOGY TRANSFER:
The current and past cross-species-transmission TSE studies have
generated a unique set of tissue reagents that
have been shared with others for research and diagnostic purposes.
This transfer of technology, along with the
immunohistochemistry test developed by Dr. Miller at NADC (used
around the world), has provided
113
diagnostic tools to many laboratories. Application of in vitro
research techniques provided critical information
to APHIS during the December 2003 diagnosis of BSE in a bovine from
Washington State.
PUBLICATIONS:
Hamir, A.N., Clark, W.W., Sutton, D.L., Miller, J.M., Stack, M.J.,
Chaplin M.J., Jenny, A.L. Resistance of
domestic cats to a US sheep scrapie agent by intracerebral route.
Journal of Veterinary Diagnostic
Investigation. 2002. v. 14. p. 444-445.
Hamir, A.N., Miller, J.M., Cutlip, R.C., Stack, M.J., Chaplin M.J.,
Jenny, A.L. Preliminary observations on the
experimental transmission of scrapie to elk (Cervus elaphus nelsoni)
by intracerebral inoculation. Veterinary
Pathology. 2003. v. 40. p. 81-85.
Hamir, A.N., Miller, J.M., Stack, M.J., Chaplin, M.J. Failure to
detect abnormal prion protein and scrapieassociated
fibrils 6 wk after intracerebral inoculation of genetically
susceptible sheep with scrapie agent.
Canadian Journal of Veterinary Research. 2002. v. 66. p. 289-294.
Hamir, R. Cutlip, J. Miller, R. Kunkle, E. Williams, M. Stack, M.
Chaplin, K. ORourke, J.A. Richt. 2004.
Experimental cross-species transmission of chronic wasting disease
to domestic livestock. J. Vet. Diagn.
Invest, in press
Hamir AN, Miller JM, Cutlip RC, Stack MJ, Chaplin MJ, Jenny AL,
Williams ES: Experimental inoculation of
scrapie and chronic wasting disease agents to raccoons (Procyon
lotor). Veterinary Record, 153: 121-123,
2003.
Hamir AN, Miller JM, Cutlip RC: Failure to detect prion protein by
immunohistochemistry in striated muscle
tissues of animals experimentally inoculated with agents of
transmissible spongiform encephalopathy.
Veterinary Pathology, (In press).
Hamir AN, Miller JM, Bartz JC, Stack MJ, Chaplin MJ: Transmission of
transmissible mink encephalopathy
(TME) to raccoons (Procyon lotor) by intracerebral inoculation.
Journal of Veterinary Diagnostic
Investigation, 15: ___ - ___, 2004 (In press).
Hamir AN, Miller JM, Cutlip RC, Kunkle RA, Jenny AL, Stack MJ,
Chaplin MJ, Richt JA: Transmission of
Sheep Scrapie to Elk (Cervus elaphus nelsoni) by Intracerebral
Inoculation: Final Outcome of the Experiment.
Journal of Veterinary Diagnostic Investigation, 15: ___ - ___, 2004
(In press).
Hamir AN, Kunkle RA, Richt JA, Miller JM, Cutlip RC, Jenny AL:
Experimental transmission of sheep
scrapie by intracerebral and oral routes to genetically susceptible
Suffolk sheep in the United States. Journal of
Veterinary Diagnostic Investigation, 2004. (Submitted).
--------------- Additional publications by scientist in this
project. ---------------
Hamir, A.N., Miller, J.M., Sonn, R.J. Meningoencephalitis and
pneumonia associated with Cryptococcus
neoformans infection in a free-ranging elk in the USA. Veterinary
Record. 2002. v. 151. p. 332-333.
114
Mueller, C.A., Richt, J.A., Meyermann, R., Deininger, M.,
Schluesener, H. 2002. Accumulation of EMAP II+
microglial cells in brains of Borna virus infected rats. Neurosci.
Lett. 339: 215-218
Hamir, A.N., Smith, B.B. Severe biliary hyperplasia associated with
liver fluke infection in an adult alpaca.
Veterinary Pathology. 2002. v. 39. p. 592-594.
Hamir, A.N., Timm, K.I. Nodular hyperplasia and cysts in thyroid
glands of llamas (Lama glama) from northwest
USA. Veterinary Record. 2003. v. 152. p. 507-508.
Palmer, M.V, Stoffregen, W.C., Rogers, D.G., Hamir, A.N., Richt,
J.A., Pederson, D., Waters, W.R. 2004.
West Nile Virus Infection in reindeer (Rangifer taratandus): report
of 4 cases. J. Vet. Diagn. Invest, in press
Kiermayer, S., Kraus, I., Richt, J.A., Garten, W., Eickmann. M.
2002. Identification of the amino terminal
subunit of the glycoprotein of Borna disease virus. FEBS Lett.
531:255-258.
Wolff, T., Unterstab, G., Heins, G., Richt, J.A., Kann, M. 2002.
Characterization of an unusual importin alpha
binding motif in the borna disease virus p10 protein that directs
nuclear import. J. Biol. Chem. 277:12151-
12157.
Dietzschold, B., Richt, J.A. (editors). 2002. Protective and
Pathological Immune Responses in the CNS. Curr.
Top. Microbiol. Immunol. 265: 1-267.
Hooper, D.C., Sauder, C., Scott, G.S., Dietzschold, B., Richt, J.A.
2002. Immunopathology and
immunoprotection in CNS virus infections: mechanisms of virus
clearance from the CNS. In: Dietzschold, B.,
Richt, J.A. (eds). Protective and Pathological Immune Responses in
the CNS. Curr. Top. Microbiol. Immunol.
265: 163-182.
Dubey JP, Hamir AN, Topper MJ: Sarcocystis mephitisi N. Sp.
(Protozoa: Sarcocystidae), Sarcocystis
neurona-like and Toxoplasma-like infections in striped skunk
(Mephitis mephitis). Journal of Parasitology. 88:
113-117, 2002.
Hamir AN, Olsen S, Rupprecht CE: Granulomatous orchitis associated
with Histoplasma-like organisms in
porcupines (Erethizon dorsatum). Veterinary Record 150: 251-252, 2002.
Hamir AN, Miller JM, Stack MJ, Chaplin MJ, Cutlip RC: Neuroaxonal
Dystrophy in Raccoons (Procyon
lotor) from Iowa. Journal of Veterinary Diagnostic Investigation.
14: 175-178, 2002.
Dubey JP, Hamir AN: Experimental toxoplasmosis in budgerigars
(Melopsittacus undulates). Journal of
Parasitology. 88: 514 - 519, 2002.
Heidari M, Hamir AN, Cutlip RC, Brogden KA: Antimicrobial anionic
peptide binds in vivo to Mannheinia
(Pasteurella) haemolytica attached to ovine alveolar epithelium. The
International Journal of Antimicrobial Agents. 20: 69-72, 2002.
Hamir AN, Stasko J, Rupprecht CE: The observation of
Helicobacter-like organisms in gastric mucosa of grey
foxes (Urocyon cinereoargenteus ) and bobcats (Lynx rufus). Canadian
Journal of Veterinary Research. (In
press).
Hamir AN, Sonn RJ, Franklin S, Wesley IV: Enteritis with intestinal
intussusception associated with
Campylobacter jejuni infection in a raccoon (Procyon lotor) kit and
isolation of C. jejuni and Arcobacter spp.
from adult raccoons. The Veterinary Record. (In press).
Sacco, R.E., Nestor, K.E., and Kunkle, R.A. Genetic variation in
response of turkeys to experimental infection
with Bordetella avium. Avian Dis. 44:197-200. 2000.
Kalfa, V.C., Jia, H.P., Kunkle, R.A., McCray, P.B. Jr., Tack, B.F.,
Brogden, K.A. Congeners of SMAP29 kill
ovine pathogens and induce ultrastructural damage in bacterial
cells. Antimicorb Agnts Chemother.
Nov;45(11):3256-61. 2001.
Brockmeier, S.L., Register, K.B., Magyar, T., Lax, A.J., Pullinger,
G.D., Kunkle, R.A. Role of the
dermonecrotic toxin of Bordetella bronchiseptica in the pathogenesis
of respiratory disease in swine. Infect
Immun. Feb:70(2):481-90. 2002.
Kunkle, R.A. Fungal Infections. In: Diseases of Poultry, 11th Ed.
Barnes, H.J., Fadly, H.M., Glisson, J.R.,
McDougold, L.R., Swayne, D.E., eds. Iowa State Press, Ames, Iowa,
U.S.A., pp. 883-896. 2003.
Kunkle, R.A. (contributor), Fowl Cholera (Avian Pasteurellosis). In:
OIE Manual of Standards for Diagnostic
Tests and Vaccines, List A and B diseases of mammals, birds and
bees. Office International des Epizooties,
Paris, France. In Press....SOME 309 PAGES...TSS

http://www.ars.usda.gov/sp2UserFiles/Program/103/7-21-04NationalProgramAssessment,AnimalHealth2000-2004.pdf

Where is there additional and updated information about CWD?


flounder@wt.net

More information about CWD is available from the following agencies:

* The New York State Department of Environmental Conservation:
http://www.dec.state.ny.us/website/dfwmr/wildlife/deer/cwd.html
* The New York State Department of Agriculture and Markets:
http://www.agmkt.state.ny.us/AI/cwd.html
* The New York State Department of Health:
http://www.nyhealth.gov/nysdoh/zoonoses/cwd.htm
* Additional information, including the status of CWD in other
states, is also available from the USDA:
http://www.aphis.usda.gov/vs/nahps/cwd/
* USGS National Wildlife Health Center:
http://www.nwhc.usgs.gov/research/chronic_wasting/chronic_wasting.html

* Chronic Wasting Disease Alliance:
http://www.cwd-info.org
* Other state agencies may have valuable information, particularly
for deer or elk from those states. Wisconsin has a particularly
useful Website with detailed information and photos for processing
deer, and a videotape and transcript addressing questions about
human health risks:
http://dnr.wi.gov/org/land/wildlife/whealth/issues/CWD/

For additional information you may contact the toll-free information
line at 1-800-808-1987.

http://www.health.state.ny.us/nysdoh/zoonoses/cwd.htm

Terry S. Singeltary Sr.
P.O. Box 42
Bacliff, Texas USA 77518






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