Diagnostic accuracy of rectal mucosa biopsy testing for chronic wasting
disease within white-tailed deer (Odocoileus virginianus) herds in North America
Effects of age, sex, polymorphism at PRNP codon 96, and disease progression
Bruce... V. Thomsen1 David A. Schneider Katherine I. O’Rourke Thomas
Gidlewski James McLane Robert W. Allen Alex A. McIsaac Gordon B. Mitchell Delwyn
P. Keane Terry R. Spraker Aru Balachandran
U.S. Department of Agriculture, National Veterinary Services Laboratories,
Ames, IA (Thomsen)
U.S. Department of Agriculture, Agricultural Research Service, Pullman, WA
(Schneider, O’Rourke)
U.S. Department of Agriculture, Animal and Plant Health Inspection Service,
Wildlife Services, Fort Collins, CO (Gidlewski)
Canadian Food Inspection Agency, Battleford, Saskatchewan, Canada (McLane)
Canadian Food Inspection Agency, Prince Albert, Saskatchewan, Canada
(Allen)
Canadian Food Inspection Agency, Saskatoon, Saskatchewan, Canada (McIsaac)
National and OIE Reference Laboratory for Scrapie and CWD, Canadian Food
Inspection Agency, Ottawa Laboratory–Fallowfield, Ottawa, Ontario, Canada
(Mitchell, Balachandran)
University of Wisconsin, Wisconsin Veterinary Diagnostic Laboratory,
Madison, WI (Keane)
Colorado State University Diagnostic Laboratory, Fort Collins, CO
(Spraker)
↵1 Bruce V. Thomsen, National Veterinary Services Laboratories, 1920 Dayton
Avenue, Ames, IA 50010. bruce.v.thomsen@aphis.usda.gov
Abstract
An effective live animal diagnostic test is needed to assist in the control
of chronic wasting disease (CWD), which has spread through captive and wild
herds of white-tailed deer (Odocoileus virginianus) in Canada and the United
States. In the present study, the diagnostic accuracy of rectal mucosa biopsy
sample testing was determined in white-tailed deer from 4 CWD-infected captive
herds. Specifically, the current study compared the immunohistochemical
detection of disease-associated prion protein in postmortem rectal mucosa biopsy
samples to the CWD status of each deer as determined by immunodiagnostic
evaluations of the brainstem at the obex, the medial retropharyngeal lymph node,
and the palatine tonsil. The effects of age, sex, genotype, and disease
progression were also evaluated. Diagnostic sensitivity on rectal biopsy samples
for CWD in white-tailed deer ranged from 63% to 100%; the pooled estimate of
sensitivity was 68% with 95% confidence limits (95% CLs) of 49% and 82%.
However, diagnostic sensitivity was dependent on genotype at prion protein gene
(PRNP) codon 96 and on disease progression as assessed by obex grade. Diagnostic
sensitivity was 76% (95% CLs: 49%, 91%) for 96GG deer but only 42% (95% CLs:
13%, 79%) for 96GS deer. Furthermore, diagnostic sensitivity was only 36% for
deer in the earliest stage of disease (obex grade 0) but was 100% for deer in
the last 2 stages of preclinical disease (obex grades 3 and 4). The overall
diagnostic specificity was 99.8%. Selective use of antemortem rectal biopsy
sample testing would provide valuable information during disease investigations
of CWD-suspect deer herds.
*** Spraker suggested an interesting explanation for the occurrence of
CWD. The deer pens at the Foot Hills Campus were built some 30-40 years ago by a
Dr. Bob Davis. At or abut that time, allegedly, some scrapie work was conducted
at this site. When deer were introduced to the pens they occupied ground that
had previously been occupied by sheep.
(PLEASE NOTE SOME OF THESE OLD UK GOVERNMENT FILE URLS ARE SLOW TO OPEN,
AND SOMETIMES YOU MAY HAVE TO CLICK ON MULTIPLE TIMES, PLEASE BE PATIENT, ANY
PROBLEMS PLEASE WRITE ME PRIVATELY, AND I WILL TRY AND FIX OR SEND YOU OLD PDF
FILE...TSS)
Wednesday, February 16, 2011
IN CONFIDENCE
SCRAPIE TRANSMISSION TO CHIMPANZEES
IN CONFIDENCE
PO-039: A comparison of scrapie and chronic wasting disease in white-tailed
deer
Justin Greenlee, Jodi Smith, Eric Nicholson US Dept. Agriculture;
Agricultural Research Service, National Animal Disease Center; Ames, IA USA
PO-081: Chronic wasting disease in the cat— Similarities to feline
spongiform encephalopathy (FSE)
High-Fence 226-Inch Whitetail Escapes, Shot in Louisiana
by Dylan Polk•December 1, 2011
Volume 18, Number 3—March 2012
Synopsis
Occurrence, Transmission, and Zoonotic Potential of Chronic Wasting Disease
Samuel E. Saunders1, Shannon L. Bartelt-Hunt, and Jason C. Bartz Author
affiliations: University of Nebraska-Lincoln, Omaha, Nebraska, USA (S.E.
Saunders, S.L. Bartelt-Hunt); Creighton University, Omaha (J.C. Bartz)
snip...
CWD has been identified in free-ranging cervids in 15 US states and 2
Canadian provinces and in ≈100 captive herds in 15 states and provinces and in
South Korea (Figure 1, panel B). Except in South Korea, CWD has not been
detected outside North America. In most locations reporting CWD cases in
free-ranging animals, the disease continues to emerge in wider geographic areas,
and prevalence appears to be increasing in many disease-endemic areas. Areas of
Wyoming now have an apparent CWD prevalence of near 50% in mule deer, and
prevalence in areas of Colorado and Wisconsin is <15 0="0" 10="10" 5="5" according="according" adult="adult" age="age" agencies.="agencies." and="and" appear="appear" areas="areas" between="between" but="but" cwd="cwd" data="data" deer.="deer." deer="deer" div="div" elk="elk" factors="factors" for="for" from="from" gene="gene" genetic="genetic" highest="highest" however="however" in="in" include="include" influence="influence" influences="influences" is="is" known="known" less="less" lower="lower" male="male" many="many" obtained="obtained" of="of" parts="parts" polymorphisms="polymorphisms" prevalence="prevalence" provincial="provincial" prp="prp" reaches="reaches" remain="remain" remains="remains" reports="reports" risk="risk" scrapie.="scrapie." sex="sex" show="show" state="state" strong="strong" susceptibility="susceptibility" than="than" the="the" to="to" understood="understood" wildlife="wildlife" wyoming.="wyoming.">
snip...
Long-term effects of CWD on cervid populations and ecosystems remain
unclear as the disease continues to spread and prevalence increases. In captive
herds, CWD might persist at high levels and lead to complete herd destruction in
the absence of human culling. Epidemiologic modeling suggests the disease could
have severe effects on free-ranging deer populations, depending on hunting
policies and environmental persistence (8,9). CWD has been associated with large
decreases in free-ranging mule deer populations in an area of high CWD
prevalence (Boulder, Colorado, USA) (5). In addition, CWD-infected deer are
selectively preyed upon by mountain lions (5), and may also be more vulnerable
to vehicle collisions (10).
snip...
Conclusions
Much remains unknown about prion diseases and CWD in particular, especially
about CWD strains (which may have varied zoonotic potentials) and the long-term
effects of CWD on cervid ecosystems. CWD prevalence and geographic range appear
likely to continue to increase. Moreover, the disease is inevitably fatal, and
no effective therapeutic measures are presently available. As such, it would
seem wise to continue research and surveillance of CWD to elucidate the details
of its transmission, pathogenesis, and continued emergence in cervid populations
in hopes that strategies for mitigating its negative effects on humans and
cervid ecosystems can be identified.
Tuesday, December 20, 2011
CHRONIC WASTING DISEASE CWD WISCONSIN Almond Deer (Buckhorn Flats) Farm
Update DECEMBER 2011
> > > The CWD infection rate was nearly 80%, the highest ever in a
North
> > > American captive herd.
Despite the five year premise plan and site decontamination, The WI DNR has
concerns over the bioavailability of infectious prions at this site to wild
white-tail deer should these fences be removed. Current research indicates that
prions can persist in soil for a minimum of 3 years.
However, Georgsson et al. (2006) concluded that prions that produced
scrapie disease in sheep remained bioavailable and infectious for at least 16
years in natural Icelandic environments, most likely in contaminated soil.
Additionally, the authors reported that from 1978-2004, scrapie recurred on
33 sheep farms, of which 9 recurrences occurred 14-21 years after initial
culling and subsequent restocking efforts; these findings further emphasize the
effect of environmental contamination on sustaining TSE infectivity and that
long-term persistence of prions in soils may be substantially greater than
previously thought. < < <
SNIP...SEE FULL TEXT ;
50 GAME FARMS IN USA INFECTED WITH CHRONIC WASTING DISEASE CWD
2012
Tuesday, December 20, 2011
CHRONIC WASTING DISEASE CWD WISCONSIN Almond Deer (Buckhorn Flats) Farm
Update DECEMBER 2011
The CWD infection rate was nearly 80%, the highest ever in a North American
captive herd.
Despite the five year premise plan and site decontamination, The WI DNR has
concerns over the bioavailability of infectious prions at this site to wild
white-tail deer should these fences be removed. Current research indicates that
prions can persist in soil for a minimum of 3 years.
However, Georgsson et al. (2006) concluded that prions that produced
scrapie disease in sheep remained bioavailable and infectious for at least 16
years in natural Icelandic environments, most likely in contaminated soil.
Additionally, the authors reported that from 1978-2004, scrapie recurred on
33 sheep farms, of which 9 recurrences occurred 14-21 years after initial
culling and subsequent restocking efforts; these findings further emphasize the
effect of environmental contamination on sustaining TSE infectivity and that
long-term persistence of prions in soils may be substantially greater than
previously thought
SNIP...SEE FULL TEXT ;
Thursday, February 09, 2012
50 GAME FARMS IN USA INFECTED WITH CHRONIC WASTING DISEASE
Friday, February 03, 2012
Wisconsin Farm-Raised Deer Farms and CWD there from 2012 report Singeltary
et al
Saturday, February 04, 2012
Wisconsin 16 age limit on testing dead deer Game Farm CWD Testing Protocol
Needs To Be Revised
Monday, June 11, 2012
OHIO Captive deer escapees and non-reporting
Ohio's testing is spontaneous and voluntary, and is limited to 16 month old
only, and only after found dead. so, the flaws there are obvious. anything
voluntary is useless, and the voluntary mad cow feed ban proved just how useless
anything voluntary is. ...
Friday, July 20, 2012
CWD found for first time in Iowa at hunting preserve
TSS
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