CWD Update 85 March 24, 2007

State and Provincial Updates

Ontario: John Dungavell, Ontario Ministry of Natural Resources, provides the following: Since 2002, Ontario has conducted CWD surveillance of hunter-harvested deer. The program has tested more than 3500 deer with all negative results to date. Ontario will continue to conduct surveillance activities in the 2007 hunting season. In 2005, the Government of Ontario developed the Ontario CWD Surveillance and Response Plan which outlines the province’s actions with regards to CWD. In November 2005, Ontario passed a regulation restricting the importation of high risk cervid parts (head, spinal column etc.) from other jurisdictions. For more information on the Ontario plan, the regulation, or our surveillance program, please see our CWD website at http://www.mnr.gov.on.ca/MNR/hunting/cwd.

Additionally, if an Ontarian harvests a CWD positive cervid in your jurisdiction, please contact John Dungavell at 705-755-1573.

Pennsylvania: Bob Boyd, Pennsylvania Game Commission, provides the following on their recent CWD exercise: On Nov. 11, 2006, Pennsylvania Game Commission (PGC) Executive Director Carl G. Roe announced that the agency would conduct a CWD response simulation exercise in the first quarter of 2007. To more fully evaluate their preparedness, the Pennsylvania Game Commission developed different scenarios for each of the six region offices and the Harrisburg headquarters. Each scenario had a different set of constructs, variables and challenges that staff had to work through. One week after the exercise commenced, each team reported on their efforts to respond to the simulated discovery of CWD. Details of each response will be incorporated into the agency’s Operational Plan. The decision to hold the drill was a product of two meetings to review and update the state’s CWD response plan, as well as the agency’s internal operational plan. “Currently, there are no confirmed or suspected cases of CWD-infected deer or elk in Pennsylvania, and we are working to ensure that it stays that way,” Roe said. “While there always is room for improvement, I believe that, having gone through this planning exercise, our agency response plan provides a solid foundation should CWD be identified within our borders.

Pennsylvania Game Commission CWD information is at: http://www.pgc.state.pa.us/pgc/cwp/view.asp?a=458&q=163873.

South Dakota: Steve Griffin, South Dakota Game, Fish, and Parks, provides the following: In the South Dakota CWD Surveillance period of July 1, 2006 to February 28, 2007 a total of 2,515 samples were collected for CWD surveillance. Breakdown of the sampling is as follows:

• 596 elk sampled—3 positive; 590 not positive; 3 pending
• 606 mule deer sampled—4 positive; 602 not positive 1,313 white-tailed deer sampled—3 positive; 1,310 not positive

Below is a listing of the positive cervids that have been found in South Dakota during the surveillance period of July 1, 2006 to February, 2007.

1. Elk female from Unit H3A in Custer County. (Hunter Harvest)
2. Elk female from Custer State Park Unit CU2 in Custer County. (Hunter Harvest)
3. Mule deer male from Unit 27A in Fall River County. (Hunter Harvest)
4. White-tailed deer male from Unit 27B in Fall River County. (Hunter Harvest)
5. White-tailed deer male from Unit 27B in Fall River County. (Hunter Harvest)
6. White-tailed deer female from Unit 21A in Pennington County. (Hunter Harvest)
7. Mule deer male from Unit 27A in Fall River County. (Hunter Harvest)
8. Mule deer male from Unit 21B in Pennington County. (Hunter Harvest)
9. Mule deer male from Unit BH1 in Custer County. (Hunter Harvest)
10. Elk female from Custer State Park Unit CU1 in Custer County. (Hunter Harvest)

In Summary: To date, South Dakota has found 57 cases of CWD (39 deer and 18 elk) in free ranging deer and elk since testing began in 1997. Wind Cave National Park accounts for 16 of these animals (8 elk, 8 deer). Three elk have been found in Custer State Park. A total of 14,817 wild deer and elk have been tested for CWD since 1997.

South Dakota Game, Fish, and Parks CWD information is at: http://www.sdgfp.info/Wildlife/hunting/BigGame/CWD.htm.

Virginia: After extensive testing, the Virginia Department of Game and Inland Fisheries (VDGIF) has not found any evidence of chronic wasting disease (CWD) in Virginia’s white-tailed deer population. In 2006, over 800 samples were collected from white-tailed deer throughout the state. Approximately 500 samples were collected from the active surveillance area, which includes the western and northern parts of Shenandoah, Frederick, Clarke and Loudoun Counties, the area of Virginia closest to where CWD has been detected in West Virginia. All hunters and members of the public are asked to keep a look out for any deer showing symptoms consistent with the disease. These clinical suspects are defined as adult (16 months or older) deer or elk that have poor body condition with neurological signs such as abnormal behavior, tremors, stumbling, incoordination, poor posture including droopy ears and a lowered head, drooling, and excessive thirst, and urination. Anyone who sees a CWD suspect deer should not attempt to contact, disturb or kill the animal. Instead, accurately document the location and immediately contact the Department of Game and Inland Fisheries by calling 1-804-367-1258.

Press Release is at: http://www.dgif.virginia.gov/news/release.asp?id=119.

Virginia Department of Game and Inland Fisheries CWD information is at: http://www.dgif.virginia.gov/cwd.

Wisconsin: Donna Gilson, Wisconsin Department of Agriculture, Trade and Consumer Protection, provides the following:

The Wisconsin Department of Agriculture, Trade and Consumer Protection (DATCP) has confirmed a second CWD-positive white-tailed deer at a Crawford County captive cervid facility. The first positive on this farm was discovered in January 2005, in a 19-month-old buck that died from respiratory causes and was routinely sampled as required for deer that die or are killed at 16 months and older. Subsequent to the initial positive, the State Veterinarian ordered the herd depopulated for testing. However, the owner challenged the USDA’s test results (the USDA’s National Veterinary Services Laboratories in Ames, Iowa, conducts Wisconsin’s captive cervid testing for regulatory purposes). That case is in federal court and therefore the depopulation order is on hold. The second positive was a male born in June 2004. It was found dead Jan. 4, 2007, after an apparent fight with another buck. Again, it was sampled as required under rule. The State Veterinarian was notified by the USDA Area Veterinarian in Charge on Feb. 5 that it was positive for CWD.

Recent Publications

Detection of PrPCWD in postmortem rectal lymphoid tissues in Rocky mountain elk (Cervus elaphus nelsoni) infected with chronic wasting disease. Terry R. Spraker, Thomas L. Gidlewski, Aru Balachandran, Kurt C. VerCauteren, Lynn Creekmore and Randy D. Munger Journal of Veterinary Diagnostic Investigation Vol. 18 Issue 6, 553-557.

Abstract: Preclinical diagnostic tests for transmissible spongiform encephalopathies have been described for mule deer (Odocoileus hemionus), using biopsy tissues of palatine tonsil, and for sheep, using lymphoid tissues from palatine tonsil, third eyelid, and rectal mucosa. The utility of examining the rectal mucosal lymphoid tissues to detect chronic wasting disease (CWD) was investigated in Rocky Mountain elk (Cervus elaphus nelsoni), a species for which there is not a live-animal diagnostic test. Postmortem rectal mucosal sections were examined from 308 elk from two privately owned herds that were depopulated. The results of the postmortem rectal mucosal sections were compared to immunohistochemical staining of the brainstem, retropharyngeal lymph nodes, and palatine tonsil. Seven elk were found positive using the brainstem (dorsal motor nucleus of the vagus nerve), retropharyngeal lymph nodes, and palatine tonsil. Six of these elk were also found positive using postmortem rectal mucosal sections. The remaining 301 elk in which CWD-associated abnormal isoform of the prion protein (PrPCWD) was not detected in the brainstem and cranial lymphoid tissues were also found to be free of PrPCWD when postmortem rectal mucosal sections were examined. The use of rectal mucosal lymphoid tissues may be suitable for a live-animal diagnostic test as part of an integrated management strategy to limit CWD in elk. http://jvdi.org/cgi/content/abstract/18/6/553.

Miscellaneous

UK Red Deer Surveillance for CWD Following agreement between the EU Commission and Member States, a one year Transmissible Spongiform Encephalopathy (TSE) surveillance programme which targets farmed and wild red deer will be undertaken across the Community. The Scottish Executive has announced details of how the surveillance protocols will apply in Scotland. With the assistance of the Deer Commission for Scotland and Forestry Commission Scotland, the sample target of 598 wild red deer animals over 18 months of age will be achieved by taking a percentage of deer culled as part of the normal stock management arrangement, with a further smaller number of animals uplifted following road kills. The sample target is expected to be collected over one hunting season. A further 598 farmed deer are also to be collected under the surveillance target. This part of the sample will be collected through a specialist deer abattoir in England. All animals collected for surveillance purposes will be subject to screening for the presence of TSEs. The sale of venison for public consumption is not under investigation and trade in venison should be unaffected.

Scotland press release at: http://www.scotland.gov.uk/News/Releases/2007/01/23140934.

More information on the UK program: http://www.defra.gov.uk/animalh/bse/pdf/comms_strat.pdf.

CWD Update 84 January 27, 2007

State and Provincial Updates

Alberta: Alberta is continuing testing for the provincial chronic wasting disease (CWD) surveillance program for 2006-07. One additional case of CWD in wild deer was confirmed on January 2. This brings the total to 17 cases in wild deer in Alberta since the first case in September 2005. The most recent case was taken by a hunter near Chauvin, not far from an earlier case reported in late December.

Alberta Sustainable Resource Development’s CWD information is at: www.srd.gov.ab.ca/fw/diseases/CWD. A map showing the locations of Alberta CWD+ animals is at: http://www.srd.gov.ab.ca/fw/diseases/CWD/pdf/CWD_positive_Dec2006.pdf.

West Virginia: On December 22, 2006 the West Virginia DNR announced that a hunter-harvested deer taken during the 2006 hunting season tested positive for CWD. The 2.5 year old buck, one of 1355 deer sampled in Hampshire County during the 2006 hunting season, was taken in close proximity to the previously-established cluster of CWD+ deer in Hampshire County. CWD has now been detected in a total of 10 deer in West Virginia, all in Hampshire County: one road-killed deer, four deer collected by the DNR in 2005, four deer collected by the DNR in 2006 and one hunter-harvested deer during the 2006 deer season.

West Virginia DNR CWD information is at: http://www.wvdnr.gov/hunting/ChronicWaste.shtm. A WVDNR fact sheet is at: http://www.wvdnr.gov/hunting/PDFFiles/CWDfactsheet.pdf.

Wisconsin: The Wisconsin DNR has begun agency sharpshooting at Devil’s Lake State Park and the Southern Unit of Kettle Moraine State Forest. Devil’s Lake S.P. is the furthest north that CWD has been detected in the state; three CWD+ deer have been detected in the 10,200 acre park in Sauk County in the last year. Kettle Moraine State Forest lies just north of the southeastern CWD zone in Wisconsin; five hunter-harvested deer from the 6400 acre Walworth County portion of the forest tested positive this year. In an additional note, the DNR has begun conducting this year’s winter helicopter deer counts in CWD-affected areas. Recent snowfall and cold temperatures are providing good conditions for these efforts to determine deer density within Wisconsin’s CWD zones.

Wisconsin Department of Natural Resources CWD information, including an interactive map showing locations of positives and overall surveillance effort, is at: http://www.dnr.state.wi.us/org/land/wildlife/whealth/issues/CWD/index.htm.

Wyoming: The Wyoming Game and Fish Department has finished its fourth year of comprehensive Chronic Wasting Disease surveillance and added two deer hunt areas and two elk hunt areas to its list of areas where CWD has been detected. Game and Fish personnel collected 4,653 deer, elk and moose samples in 2006. Of those, 116 animals tested positive for CWD – 88 mule deer, 13 white-tailed deer and 15 elk. New cases of CWD were diagnosed in deer hunt area 4 east of Sundance, deer hunt area 11 in Niobrara and Weston counties and elk hunt areas 16 and 22 in northern Carbon County.

The Wyoming Game & Fish Department 2006 surveillance summary press release is at: http://gf.state.wy.us/services/news/pressreleases/06/12/15/061215_2.asp. Wyoming Game & Fish Department CWD Information is at: http://gf.state.wy.us/services/education/cwd/index.asp.

Recent Publications

Production of cattle lacking prion protein. Jürgen A Richt, Poothappillai Kasinathan, Amir N Hamir, Joaquin Castilla, Thillai Sathiyaseelan, Francisco Vargas, Janaki Sathiyaseelan, Hua Wu, Hiroaki Matsushita, Julie Koster, Shinichiro Kato, Isao Ishida, Claudio Soto, James M Robl & Yoshimi Kuroiwa Nature Biotechnology 25, 132-138 (2006).

Abstract: Prion diseases are caused by propagation of misfolded forms of the normal cellular prion protein PrPC, such as PrPBSE in bovine spongiform encephalopathy (BSE) in cattle and PrPCJD in Creutzfeldt-Jakob disease (CJD) in humans. Disruption of PrPC expression in mice, a species that does not naturally contract prion diseases, results in no apparent developmental abnormalities. However, the impact of ablating PrPC function in natural host species of prion diseases is unknown. Here we report the generation and characterization of PrPC-deficient cattle produced by a sequential gene-targeting system. At over 20 months of age, the cattle are clinically, physiologically, histopathologically, immunologically and reproductively normal. Brain tissue homogenates are resistant to prion propagation in vitro as assessed by protein misfolding cyclic amplification. PrPC-deficient cattle may be a useful model for prion research and could provide industrial bovine products free of prion proteins. http://www.nature.com/nbt/journal/v25/n1/abs/nbt1271.html

The role of the cellular prion protein in the immune system. J. D. Isaacs, G. S. Jackson, and D. M. Altmann Clinical & Experimental Immunology 146 (1), 1–8 (2006).

Abstract: Prion protein (PrP) plays a key role in the pathogenesis of prion diseases. However, the normal function of the protein remains unclear. The cellular isoform (PrPC) is expressed widely in the immune system, in haematopoietic stem cells and mature lymphoid and myeloid compartments in addition to cells of the central nervous system. It is up-regulated in T cell activation and may be expressed at higher levels by specialized classes of lymphocyte. Furthermore, antibody cross-linking of surface PrP modulates T cell activation and leads to rearrangements of lipid raft constituents and increased phosphorylation of signalling proteins. These findings appear to indicate an important but, as yet, ill-defined role in T cell function. Although PrP-/- mice have been reported to have only minor alterations in immune function, recent work has suggested that PrP is required for self-renewal of haematopoietic stem cells. Here, we consider the evidence for a distinctive role for PrPC in the immune system and what the effects of anti-prion therapeutics may be on immune function. http://www.blackwell-synergy.com/doi/abs/10.1111/j.1365-2249.2006.03194.x.

Prions and their partners in crime. Byron Caughey and Gerald S. Baron Nature 443, 803-810 (19 October 2006)

Abstract: Prions, the infectious agents of transmissible spongiform encephalopathies (TSEs), have defied full characterization for decades. The dogma has been that prions lack nucleic acids and are composed of a pathological, self-inducing form of the host’s prion protein (PrP). Recent progress in propagating TSE infectivity in cell-free systems has effectively ruled out the involvement of foreign nucleic acids. However, host-derived nucleic acids or other non-PrP molecules seem to be crucial. Interactions between TSE-associated PrP and its normal counterpart are also pathalogically important, so the physiological functions of normal PrP and how they might be corrupted by TSE infections have been the subject of recent research. http://www.nature.com/nature/journal/v443/n7113/abs/nature05294.html.

The following review article, authored by Beth Williams, was published in 2005, following her unfortunate and untimely death. While aspects of our knowledge regarding CWD have been updated by more recent science, this review article is probably the most thorough ever written and is highly recommended to bolster the reader’s overall understanding of CWD.

Chronic Wasting Disease. E. S. Williams Veterinary Pathology 42:530–549 (2005)

Abstract: Chronic wasting disease (CWD) is a unique transmissible spongiform encephalopathy (TSE) of mule deer (Odocoileus hemionus), white-tailed deer (O. virginianus), and Rocky Mountain elk (Cervus elaphus nelsoni). The natural history of CWD is incompletely understood, but it differs from scrapie and bovine spongiform encephalopathy (BSE) by virtue of its occurrence in nondomestic and free-ranging species. CWD has many features in common with scrapie, including early widespread distribution of disease-associated prion protein (PrPd) in lymphoid tissues, with later involvement of central nervous system (CNS) and peripheral tissues. This distribution likely contributes to apparent efficiency of horizontal transmission and, in this, is similar to scrapie and differs from BSE. Clinical features and lesions of CWD are qualitatively similar to the other animal TSEs. Microscopically, marked spongiform lesions occur in the central nervous system (CNS) after a prolonged incubation period and variable course of clinical disease. During incubation, PrPd can be identified in tissues by antibody-based detection systems. Although CWD can be transmitted by intracerebral inoculation to cattle, sheep, and goats, ongoing studies have not demonstrated that domestic livestock are susceptible via oral exposure, the presumed natural route of exposure to TSEs. Surveillance efforts for CWD in captive and free-ranging cervids will continue in concert with similar activities for scrapie and BSE. Eradication of CWD in farmed cervids is the goal of state, federal, and industry programs, but eradication of CWD from free-ranging populations of cervids is unlikely with currently available management techniques. http://www.vetpathology.org/cgi/content/abstract/42/5/530.

Upcoming Conferences

Transmissible Spongiform Encephalopathies: The Definitive American TSE Meeting February 12-13, 2007, Baltimore, Maryland http://www.healthtech.com/2007/tse/index.asp

CWD Update 82 November 20, 2006

State Updates

New York: John Major, New York Department of Environmental Conservation (DEC), provides the following: For 2006, Chronic Wasting Disease regulations in New York have been updated in response to the finding of the disease in a moose in Colorado and deer in West Virginia. Hunters bringing carcasses into New York from West Virginia must now process them to remove tissues of concern prior to import, and moose have been added to the list of susceptible species that previously included deer and elk. Last year, more than 8,000 wild deer were tested for CWD in New York following the discovery of CWD in 2 wild and 5 captive deer in April 2005, and no additional animals have tested positive for the disease. Special restrictions are in place within the CWD Containment Area of Oneida and Madison counties governing how harvested deer and specific deer parts may be possessed, transported, and disposed. Mandatory testing of all deer taken in the Containment Area will be occurring again this fall, as well as random testing in other counties throughout New York State. Surveillance will continue at the same level this year. As of November 17, more than 3,200 samples (including more than 800 from the Containment Area) have been tested this year, none have detected CWD. The NY DEC maintains CWD information at: http://www.dec.state.ny.us/website/dfwmr/wildlife/deer/cwd.html.

Wisconsin: The Wisconsin DNR has been diligently working to manage CWD since it was detected in free-ranging deer in 2002. In September, DNR staff held a retreat to discuss their progress, relevant science, and future management options. On October 25, WDNR Secretary Scott Hassett presented a memo to the WI DNR Board, outlining the CWD situation in Wisconsin. Secretary Hassett’s memo can be viewed at: http://www.dnr.state.wi.us/org/land/wildlife/whealth/issues/cwd/doc/Hasset_CWDMgmt.pdf.

Also in Wisconsin, the Legislative Audit Bureau recently completed an audit of Wisconsin’s CWD program. The results of the audit (98 page report) can be obtained at: http://www.legis.state.wi.us/lab/reports/06-13Full.pdf. The four page summary report is at: http://www.legis.state.wi.us/lab/reports/06-13Full.pdf. Response from the Wisconsin DNR, including their formal response and press release are at: http://www.dnr.state.wi.us/org/land/wildlife/whealth/issues/CWD/index.htm.

Wyoming: A male white-tailed deer killed in Hunt Area 4, east of Sundance in the Moskee area on November 4, 2006 has tested positive for CWD. Hunt Area 4 borders the Wyoming/South Dakota state line. This is the first CWD-positive animal reported in this hunt area. Press Release available at: http://gf.state.wy.us/services/news/pressreleases/06/11/17/061117_3.asp Wyoming G&F CWD information is at: http://gf.state.wy.us/services/education/cwd/index.asp.

Northeast Association of Fish and Wildlife Agencies: On November 2, 2006, the Northeast Association adopted a regional CWD Plan. Here (PDF) is a link to the document.

Infectious agent of sheep scrapie may persist in the environment for at least 16 years. Gudmundur Georgsson, Sigurdur Sigurdarson and Paul Brown J Gen Virol 87 (2006), 3737-3740; DOI 10.1099/vir.0.82011-0

Abstract: In 1978, a rigorous programme was implemented to stop the spread of, and subsequently eradicate, sheep scrapie in Iceland. Affected flocks were culled, premises were disinfected and, after 2–3 years, restocked with lambs from scrapie-free areas. Between 1978 and 2004, scrapie recurred on 33 farms. Nine of these recurrences occurred 14–21 years after culling, apparently as the result of environmental contamination, but outside entry could not always be absolutely excluded. Of special interest was one farm with a small, completely self-contained flock where scrapie recurred 18 years after culling, 2 years after some lambs had been housed in an old sheep-house that had never been disinfected. Epidemiological investigation established with near certitude that the disease had not been introduced from the outside and it is concluded that the agent may have persisted in the old sheep-house for at least 16 years. http://vir.sgmjournals.org/cgi/content/abstract/87/12/3737

A blood test for prion: disease associated prion aggregate is detected in the blood of infected but asymptomatic animals. Binggong Chang, Xin Cheng, Shaoman Yin, Tao Pan, Hongtao Zhang, Poki Wong, Shin-Chung Kang, Fan Xiao, Huimin Yan, Chaoyang Li, Lisa L. Wolfe, Michael W. Miller, Thomas Wisniewski, Mark I. Greene, and Man-Sun Sy Clin. Vaccine Immunol. doi:10.1128/CVI.00341-06

Abstract: We have developed a sensitive in vitro assay for detecting disease associated prion aggregates by combining an aggregation specific enzyme-linked immunosorbent assay (AS-ELISA) with a Fluorescent Amplification Catalyzed by T7 RNA polymerase Technique (FACTT). The new assay, named AS-FACTT, is much more sensitive than AS-ELISA and could detect prion aggregates in the brain of mice as early as 7 days after an intra-peritoneal inoculation of PrPSc. However, AS-FACTT was still unable to detect prion aggregates in blood of infected mice. To further improve the detection limit of AS-FACTT, we added an additional prion amplification step (Am) and developed a third generation assay, termed Am-A-FACTT. Am-A-FACTT has 100% sensitivity and specificity in detecting disease-associated prion aggregates in blood of infected mice at late but still asymptomatic stages of disease. At a very early stage, Am-A-FACTT had a sensitivity of 50% and specificity of 100%. Most importantly, Am-A-FACTT also detects prion aggregates in blood of mule deer infected with a naturally occurring prion disease, chronic wasting disease. Application of this assay to cattle, sheep, and humans could safeguard food supplies and prevent human contagion. http://cvi.asm.org/cgi/content/abstract/CVI.00341-06v1

Spatial Epidemiology of Chronic Wasting Disease in Wisconsin White-Tailed Deer. Damien O. Joly, Michael D. Samuel, Julia A. Langenberg, Julie A. Blanchong, Carl A. Batha, Robert E. Rolley, Delwyn P. Keane and Christine A. Ribic Journal of Wildlife Diseases, 42(3), 2006, pp. 578-588

Abstract: Chronic wasting disease (CWD) is a fatal, emerging disease of cervids associated with transmissible protease-resistant prion proteins. The potential for CWD to cause dramatic declines in deer and elk populations and perceived human health risks associated with consuming CWD-contaminated venison have led wildlife agencies to embark on extensive CWD control programs, typically involving culling to reduce deer populations. We characterized the spatial distribution of CWD in white-tailed deer (Odocoileus virginianus) in Wisconsin to facilitate CWD management. We found that CWD prevalence declined with distance from a central location, was locally correlated at a scale of 3.6 km, and was correlated with deer habitat abundance. The latter result is consistent with patterns expected for a positive relationship between density and prevalence of CWD. We recommend management activities focused on culling in geographic areas with high prevalence to have the greatest probability of removing infected individuals. Further research is needed to elucidate the factors involved in CWD spread and infection rates, especially the role of density-dependent transmission. http://www.jwildlifedis.org/cgi/content/abstract/42/3/578

White-Tailed Deer Harvest from the Chronic Wasting Disease Eradication Zone in South-Central Wisconsin. Julie A. Blanchong, Damien O. Joly, Michael D. Samuel, Julia A. Langenberg, Robert E. Rolley and Janet F. Sausen Wildlife Society Bulletin 34(3):725-731

Abstract: Chronic wasting disease (CWD) was discovered in free-ranging white-tailed deer (Odocoileus virginianus) in south-central Wisconsin in 2002. The current control method for CWD in the state is the harvest of deer from affected areas to reduce population density and lower CWD transmission. We used spatial regression methods to identify factors associated with deer harvest across south-central Wisconsin. Harvest of deer by hunters was positively related to deer density (slope¼0.003, 95%CI¼0.0001–0.006), the number of landowners that requested harvest permits (slope¼0.071, 95% CI¼0.037–0.105), and proximity to the area of highest CWD infection (slope¼_0.041, 95% CI¼_0.056–_0.027). Concomitantly, harvest was not impacted in areas where landowners signed a petition protesting intensive deer reduction (slope ¼_0.00006, 95% CI ¼_0.0005–0.0003). Our results suggest that the success of programs designed to reduce deer populations for disease control or to reduce overabundance in Wisconsin are dependent on landowner and hunter participation. We recommend that programs or actions implemented to eradicate or mitigate the spread of CWD should monitor and assess deer population reduction and evaluate factors affecting program success to improve methods to meet management goals.

Passage of chronic wasting disease prion into transgenic mice expressing Rocky Mountain elk (Cervus elaphus nelsoni) PrPC. Giuseppe LaFauci, Richard I. Carp, Harry C. Meeker, Xuemin Ye, Jae I. Kim, Michael Natelli, Marisol Cedeno, Robert B. Petersen, Richard Kascsak and Richard Rubenstein J Gen Virol 87 (2006), 3773-3780; DOI 10.1099/vir.0.82137-0

Abstract: Chronic wasting disease (CWD) of elk (Cervus elaphus nelsoni) and mule deer (Odocoileus hemionus) is one of three naturally occurring forms of prion disease, the others being Creutzfeldt–Jakob disease in humans and scrapie in sheep. In the last few decades, CWD has spread among captive and free-ranging cervids in 13 US states, two Canadian provinces and recently in Korea. The origin of the CWD agent(s) in cervids is not known. This study describes the development of a transgenic mouse line (TgElk) homozygous for a transgene array encoding the elk prion protein (PrPC) and its use in propagating and simulating CWD in mice. Intracerebral injection of one mule deer and three elk CWD isolates into TgElk mice led to disease with incubation periods of 127 and 95 days, respectively. Upon secondary passage, the incubation time was reduced to 108 and 90 days, respectively. Upon passage into TgElk mice, CWD prions (PrPSc) maintained the characteristic Western blot profiles seen in CWD-affected mule deer and elk and produced histopathological modifications consistent with those observed in the natural disease. The short incubation time observed on passage from cervid to mouse with both mule deer and elk CWD brain homogenates and the demonstrated capacity of the animals to propagate (mouse to mouse) CWD agents make the TgElk line a valuable model to study CWD agents in cervid populations. In addition, these results with this new transgenic line suggest the intriguing hypothesis that there could be more than one strain of CWD agent in cervids. http://vir.sgmjournals.org/cgi/content/abstract/87/12/3773

Upcoming Conferences:

The 67th Midwest Fish and Wildlife Conference December 3-6, 2006 Omaha, Nebraska http://www.ngpc.state.ne.us/midwest2006 A special CWD session will be held on Tuesday, December 5. Eleven papers on CWD will be presented. Titles and abstracts are available on the conference web site. Click on “Program @ Glance” then “CWD Symposium.”

Transmissible Spongiform Encephalopathies: The Definitive American TSE Meeting February 12-13, 2007 Baltimore, Maryland http://www.healthtech.com/2007/tse/index.asp The conference agenda can be downloaded from the conference web site. Early registration closes December 1.

CWD UPDATE 81 November 14, 2006

USDA-APHIS-Veterinary Services has published a request for comments on the three petitions received from the Association of Fish and Wildlife Agencies, the U. S. Animal Health Association, and the National Assembly of State Animal Health Officials protesting portions of their rule on the interstate transportation of captive cervids and the federal herd-monitoring program. The notice was in the Federal Register of November 3, 2006 and can be accessed here. It is very important that all interested parties review this notice and submit comments. The two main issues are the preemption of state authority and allowing movement across state lines after only one year of monitoring, gradually increasing to 5 years.

An elk killed recently in the Shirley Mountains northwest of Medicine Bow, Wyoming has tested positive for chronic wasting disease. The hunter-killed elk comes from Hunt Area 16 where CWD had been detected in deer previously, although this is the first elk from that hunt unit to test positive. Elk in two other elk hunt areas immediately to the east and south of Hunt Area 16 have tested positive for the disease in past years. The Colorado Division of Wildlife reports finding two additional positive moose. The two bull moose were harvested legally in northern Colorado near Glendevey recently. One of the moose was from the same herd that the first positive moose was from. This brings the total wild moose positive for CWD to 3 out of 528 tested in Colorado.

Results for CWD testing in South Dakota from July 1 to November 13, 2006 have been reported by South Dakota Game, Fish, and Parks. The samples tested and results are; 444 elk sampled–438 results returned as NOT Positive–4 results pending (2 POSITIVE ELK FOUND), 111 mule deer sampled–26 results returned as NOT Positive–85 results pending, 402 white-tailed deer–44 results returned as NOT Positive– 358 results pending The two positive elk were both female and hunter harvested. Both were from Custer County, one being taken in Custer State Park. To date, South Dakota has found 49 cases of CWD (32 deer and 17 elk) in free ranging deer and elk since testing began in 1997. Wind Cave National Park accounts for 16 of these animals (8 elk, 8 deer). A total of 13,262 wild deer and elk have been tested for CWD since 1997.

Wisconsin DNR reports on results to date for this years testing. During the fall hunting season (still in progress), they have collected 5,429 samples and received results from 3,456 of these. There were 6 positive in this number, 4 from the disease eradication zone and 2 from the herd reduction zone. This brings their totals to 105,594 animals sampled with 657 positive.

The New Mexico Game and Fish Department reports that they have detected CWD in one mule deer on the Stallion site of White Sands Missile Range. This location is approximately 100 miles north of the main infection area near the Missile Range headquarters and 75 miles north of the focus of infection in the southern Sacramento Mountains. The Wyoming Game and Fish Department reports that a white-tailed deer harvested in Hunt Area 9 near Newcastle has tested positive for chronic wasting disease. The disease had not previously been found in deer Hunt Area 9. The deer was harvested on a ranch southeast of Newcastle in early October. The location is approximately 18 miles from where the disease has been found in South Dakota in the same drainage.

OK, this is it, my very last and final CWD update. My last day of work is next Wednesday, November 22, 2006. I will be enjoying the mountains of northern New Mexico and trying my hand at fishing and hunting again. I have been blessed by my association with the brightest and best in our business and will miss the friendships and camaraderie from times past. Bryan Richards, CWD Project Leader for the National Wildlife Health Lab in Madison, Wisconsin has agreed to take over the responsibility of issuing these updates. Lets all help Bryan out by providing him with information on what is going on in your neck of the woods as concerns CWD so he can get the information out to others. Bryan’s email is [email protected]. If you need to talk to Bryan, he can be reached at 608-270-2485. Thanks Bryan for taking on this job, and thanks to each and every one reading this for their help and friendship during these interesting years. I will plan on keeping in touch through the updates and will be doing a little consulting, so might see some of you at future meetings (if it doesn’t interfere with my hunting and fishing). Goodbye and God Bless.

WASHINGTON, Nov. 2, 2006–The U.S. Department of Agriculture’s Animal and Plant Health Inspection Service is soliciting comments on three petitions requesting that APHIS reconsider provisions and delay a recent final rule establishing a herd certification program and interstate movement restrictions for cervids to control the spread of chronic wasting disease (CWD). The CWD herd certification program and interstate movement of farmed or captive deer, elk and moose final rule, published on July 21, originally had an effective date of Oct. 19. However, in early August, APHIS received petitions from the Association of Fish and Wildlife Agencies, the National Assembly of State Animal Health Officials and the United States Animal Health Association asking for a delay and review. APHIS is taking this opportunity to solicit comments on the merits of these three petitions.

While the public is invited to comment on any of the issues raised by the petitions, APHIS is particularly interested in receiving comments related to the following areas:

• Consider the alternatives of implementing a federal interstate movement standard versus allowing individual state standards to apply? What hardships or benefits would each alternative impose?

• With respect to the spread of CWD, in addition to the requirements established by the APHIS CWD rule, what additional safeguards do states need to mitigate or reduce the risk of disease transmission and why are they needed?

• What practical or operational problems may be expected from the final rule and from the alternatives suggested by the petitions? How could they be alleviated; and

• Are there any alternatives that could address the petitioners’ concerns, other than allowing the movement requirements of individual states to take precedence over the federal standard?

The notice requesting comments on the petition is scheduled for publication in the Nov. 3 Federal Register.

Consideration will be give to comments received on or before Dec. 4. Send an original and three copies of postal or commercial delivery comments to Docket APHIS-2006-0118, Regulatory Analysis and Development, PPD, APHIS, Station 3A-03.8, 4700 River Road, Unit 118, Riverdale, Md. 20737-1238. If you wish to submit a comment using the Internet go to the

Federal eRulemaking portal, select “Animal and Plant Health Inspection Service” from the agency drop-down menu; then click on “Submit.” In the Docket ID column, select APHIS-2006-0118 to submit or view public comments and to view supporting and related materials available electronically.

Comments are posted on the Regulations.gov Web site and may also be reviewed at USDA, Room 1141, South Building, 14th St. and Independence Ave., S.W., Washington, D.C., between 8 a.m. and 4:30 p.m., Monday through Friday, excluding holidays. To facilitate entry into the comment reading room, please call (202) 690-2817.