Features

Chronic Wasting Disease Update - 10/17/03

The Utah Division of Wildlife Resources reports additional CWD positive mule deer.  The latest was from Sanpete County in central Utah.  This is the farthest west CWD has been confirmed and is not close to the previous positives in Utah.  This case was from a deer taken on a depredation problem and was to be used as a training carcass for testing samples.

The Wyoming Game and Fish Department reports additional areas where CWD has been found.  The latest cases are in the Black Hills area of northeastern Wyoming.  Two mule deer and two white-tailed deer in four northeastern Wyoming hunt areas tested positive for the fatal brain malady during recent sampling efforts.  These positives are near the towns of Lusk and Moorcroft.

The Alaska Department of Fish and Game reports that they will test 500 deer and as many elk as possible for CWD on Kodiak Island this fall.  They are working with USDA-APHIS to conduct tests to determine if CWD has infected cervids in that state.

Montana Fish, Wildlife and Parks reports that 24 elk have escaped from a captive cervid facility in that state.  Biologists and others from the agency are attempting to locate and remove these animals.  Five of the animals have been recovered by the owner and employees of the state agency have removed an additional 13 animals.  Six bulls remain at large.  All animals collected will be tested for CWD.

Montana has won another victory in the ongoing suite of lawsuits over the voter passed initiative banning new game farms and outlawing the "hunting" of captive animals.  U.S. District Judge Sam Haddon ruled against game farmers who claimed the state robbed them of property rights.  Haddon rejected the game farmers' claim, noting that landowners have no "absolute or unfettered right" to operate game farms.  What's more, he ruled, the state has a legitimate interest in protecting wildlife.

A second deer from a Portage County, Wisconsin captive facility has tested positive for CWD.  This was an adult buck and had only been on the facility for 6 days, indicating infection in another location.  The animal was a shooter buck that had been moved from another captive facility in Rock County near Beloit, Wisconsin.  The Portage County facility is the one challenging the depopulation order in court and is currently under quarantine.  The facility near Beloit has also been placed under quarantine.

The Michigan Chronic Wasting Disease Task Force, appointed earlier this year by Governor Jennifer Granholm, has issued their final report of recommendations for keeping the disease out of Michigan.  A full copy of the report can be downloaded from the Michigan State Government web site.

Visit the CWD Alliance web site (www.cwd-info.org) for a table showing the various state importation laws.

Chronic Wasting Disease - An Overview by Mike Schlegel, Conservation Committee Member

Chronic Wasting Disease (CWD) has been attracting the attention of wildlife management agencies as well as sportsmen in recent months.  This disease has the potential to significantly change wildlife management and sport hunting.  Recently a Chronic Wasting Disease Alliance was formed.  The Pope and Young Club is a member of the Alliance.  The following is the mission statement for the Alliance:  "The mission of the CWD Alliance is to promote responsible and accurate communications regarding CWD, and to support strategies that effectively control CWD to minimize its impact on wild, free-ranging deer and elk populations.  The CWD Alliance and its partner organizations are committed to providing timely, scientifically accurate information regarding chronic wasting disease, its impact on wildlife and humans, and recommendations for its control."

In addition to being a member of the CWD Alliance, the Pope and Young Club was also one of the sponsors of a Chronic Wasting Disease Symposium, held in Denver, Colorado on August 6 and 7, 2002.  The Pope and Young Club sent two representatives to the symposium:  Second Vice-President Doug Clayton, of Iowa, and Conservation Committee Member Mike Schlegel, of Idaho.  The following is a synopsis of the symposium.  Specifically, what is chronic wasting disease, where it has been documented, how wide spread is it, what are the symptoms, how is it transmitted, how is it detected, are humans susceptible, precautions hunters should take, precautions management agencies are taking, and unknowns about CWD.

Chronic wasting disease appears to be limited to whitetailed deer, mule deer and elk.  CWD is caused by a prion (pri' on).  A prion is a mutant protein that lacks nucleic acids.  They belong to a group called transmissible spongiform encephalopathy (TSE) diseases.  Prions are not living organisms like a bacteria or virus.  However, they do have the ability to divide and multiply.  Prions infect the brain, destroying brain tissue, thereby interrupting normal body function.  There is no treatment for CWD and infected animals die.  Prions are responsible for "scrapie" in domestic sheep and "mad cow disease" in cattle.  Mad cow disease, in turn, infects humans resulting in a disease called Creutzfeldt-Jakob disease (CJD).  Although there is no indication that CWD will infect humans at this point in time, there is still reason for great concern.

CWD was first detected in free ranging deer in 1967 in Colorado and shortly thereafter in Wyoming.  Initially the disease was confined to northeast Colorado and southeast Wyoming.  However, as of August 2002, CWD has been detected in free ranging deer and/or elk in the following areas:  Colorado, Minnesota, Nebraska, New Mexico, Saskatchewan, South Dakota, Wisconsin and Wyoming.

CWD was first identified in a game ranch in South Dakota in 1997.  Since that time the disease has been documented on 23 additional ranches in six states:  Colorado, Kansas, Montana, Nebraska, Oklahoma and South Dakota.  CWD was first detected on a Canadian game ranch in 1996 and has been confirmed in captive elk herds in Alberta and Saskatchewan.

CWD is very difficult to monitor and track.  The disease is confirmed by testing brain and/or lymph tissue from dead animals.  Also there is no information on how the disease is transmitted.  Currently there are three theories:  female to offspring, animal to animal (direct contact), and environmental contamination by diseased animals (indirect contact).  Environmental contamination has the strongest support at this point in time.  Areas where animals congregate seem to be a common denominator where CWD has been detected.  Such areas include artificial feeding sites, watering areas and game ranching operations.

The only reliable diagnostic techniques include histopathology, immunohistochemistry and electron microscopic examination of selected brain tissue.  Currently there is no reliable test for CWD in live animals.  However immunohistochemistry on tonsil tissue taken from live animals is showing promise.  Unfortunately, the animal has to be anesthetized, plus specialized equipment is required to collect the tonsil tissue.  Thus, this technique has limited field application.

In order to determine the prevalence of CWD, wildlife management agencies in the endemic areas are sampling hunter-killed deer/elk as well as conducting site specific collections.  Fortunately, at this point in time, CWD appears to affect only a few animals within infected deer and elk herds.  However the infection rate does appear to be higher in deer herds than in elk herds.  For example, within the endemic area in Colorado, the prevalence of CWD in mule deer ranges between 1% and 11% and averages 5%.  The prevalence in elk in the same area is less than 1%.  In Wyoming since 1997, the prevalence of CWD in the endemic area is 12% in mule deer, 16% for white-tailed deer and almost 3% for elk.  The Nebraska Game and Parks Commission has sampled free-ranging deer and elk since 1997.  To date 2,900 deer and 150 elk have been tested for CWD.  Fifteen deer, five mule deer and ten white-tailed deer, have tested positive.  No elk were positive.  Also, in Nebraska three game ranching operations tested positive for CWD.  One of the ranches has since been declared CWD free.  The other two ranches were depopulated.  At one these ranches, 98 of 191 deer (53%) and 7 of 74 elk (9%) tested positive.

In addition to sampling free-ranging deer and elk herds for CWD, wildlife management agencies are also initiating management and research programs to better understand and control CWD.  Because high animal density appears to be a common factor associated with CWD, agencies are reducing deer and elk populations in endemic areas.  Movement and distribution studies have been intensified in endemic areas.  States are adopting regulations that prohibit the importation of live deer and elk into their respective states.  Several states have initiated this regulation since the August symposium.  The Oregon Fish and Wildlife Commission, for example, initiated this regulation on August 9th, two days after the symposium.  The Idaho Fish and Game Commission followed suit a week after the symposium.  In many states the game ranching rules and regulations fall under the jurisdiction of state agriculture departments.  In Idaho, for example, although the Fish and Game Commission has prohibited the importation of live deer and elk, the Department of Agriculture has not prohibited the importation of live deer and elk from game ranches.  It is imperative that all state and federal agencies work together in preventing and controlling the spread of CWD.  Now is not the time for turf battles.  There is simply too much at stake!

It appears there is lots of money in the pipeline for CWD research.  In that light, it was rewarding to detect a theme of state/federal cooperation and communication regarding CWD.  The federal agencies openly admitted the rights of the individual states to manage resident wildlife.  In short, there was an overall spirit of cooperation.  It was also rewarding to learn there would be a coordinated CWD research effort that will also cross state/federal lines.

Both the World Health Organization and the Centers for Disease Control have concluded there is no indication that CWD can infect humans.  After 16 years of monitoring in the Colorado endemic area there is no evidence that CWD infects humans.  The World Health Organization does, however, recommend humans not eat any part of any deer or elk suspected of having CWD.

Hunters can contact the state wildlife management agencies in the state(s) they plan to hunt for information on CWD and the availability of testing harvested animals if concerned about CWD.

The following guidelines were offered to hunters concerned about CWD:

• Do not shoot, handle or consume any animal that is acting abnormally or appears to be sick.
• Wear latex or rubber gloves when field dressing deer and elk.
• Bone out the meat.  Don't saw through bone, and avoid cutting through the brain or spinal cord (backbone).
• Minimize the handling of brain and spinal tissues.
• Wash hands and instruments thoroughly after field dressing is complete.
• Avoid consuming brain, spinal cord, eyes, spleen, tonsils and lymph nodes of harvested game.
• Avoid consuming the meat of any animal that tests positive for the disease.
• If the deer or elk is commercially processed, it should be processed individually, without meat from other animals being mixed together.

Wildlife management agencies need the assistance of hunters in detecting CWD.  Please cooperate in providing tissue samples when requested.  Also report any deer or elk exhibiting the following symptoms:

• Abnormal behavior
• Poor body condition
• Head held in lowered position
• Excessive salivation
• Droopy ears
• Grinding teeth

If you encounter an animal displaying the above symptoms notify a representative of the wildlife management agency as soon as possible, even if it requires sacrificing some hunting time.

You can keep abreast of CWD at the following web sites:

• Chronic Wasting Disease Alliance - http://www.cwd-info.org/
• Whitetails Unlimited - www.whitetailsunlimited.com
• Canadian Food Inspection Agency (CFIA) - http://www.cfia
• Colorado Division of Wildlife (CDOW) - http://wildlife.state.co.us/hunt/huntereducation/chronic.asp
• FDA Transmissible Spongiform Encephalopathy Advisory Comittee - www.fda.gov/ohrms/dockets/ac/01/transcripts/3681t2_02.pdf
• Nebraska Game and Parks Commission - http://www.ngpc.state.ne.us/furdocs/CWDmaps.html
• U.S. Animal Health Association - http://www.usaha.org/reports/reports01/r01wd.html
• U.S. Department of Agriculture - http://www.aphis.usda.gov/vs/cwd_program.html
• World Health Organization - http://www.who.int/emc-documents/tse/whocdscsraph2002c.html
• http://www.maddeer.org/

This is by no means a complete list of available sources of information. As a member of the Chronic Wasting Disease Alliance, the Pope and Young Club will have access to the current status of CWD.  The Club will provide periodic CWD updates in the Newsletter and on the web site.

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