Chronic Wasting Disease:
Frequently Asked Questions

Developed with Minnesota state agencies and associations

The Disease

What is Chronic Wasting Disease (CWD)?
CWD is a fatal brain and nervous system disease in deer and elk. It is different than mad cow disease in cattle and scrapie in sheep, but is in the same category of diseases called transmissible spongiform encephalopathys or TSEs.

What causes CWD?
CWD is caused by an abnormally-shaped protein called a prion. Prions are not viruses, bacteria or living organisms but are able to increase in numbers in the brain and nervous system of an infected animal. The disease is slow to develop from the time the animal is exposed until the time it actually shows any signs of the disease (more than a year).

What are the clinical signs of CWD?
Deer and elk with CWD show weight loss, listlessness, abnormal behavior (including loss of fear of humans, staggering, excessive drooling, drinking large amounts of water, and frequent urination), drooping ears and rough coat.

Can CWD be treated?
No, it is a fatal disease with no known treatment. Research is underway to identify and develop treatment possibilities.

Where and how did CWD originate?
The exact origin is unknown. It was first observed in mule deer at a Colorado research facility in the late 1960s.

What game or wildlife are affected by CWD?
Only four members of the deer and elk family are known to be susceptible to CWD: elk, mule deer, black-tailed deer and white-tailed deer. Bighorn sheep and pronghorn antelope have not developed CWD even when exposed under research conditions. No other animals have been found to be affected by CWD.

Occurrence

Is CWD found in Minnesota?
CWD was found in a single animal on a central Minnesota elk farm in August of 2002. It has not been found in free-ranging or wild deer in Minnesota to date.

Where has CWD been found?
Most of the early known CWD cases were identified in northeastern Colorado and southeastern Wyoming. CWD has been diagnosed in farmed elk herds in Colorado, Kansas, Montana, Nebraska, Oklahoma, South Dakota, and Saskatchewan and Alberta, Canada. Cases have been found in wild deer in South Dakota, Wisconsin, Wyoming, Colorado, Nebraska, New Mexico and Saskatchewan, Canada.

What is being done about CWD in Minnesota?
All of the elk on the farm where CWD was found are being euthanized and tested for the disease. The Minnesota Department of Natural Resources (DNR) has collected more than 90 free-roaming deer in the immediate area around this farm. Tests conducted on these deer have not found any CWD. The DNR will be conducting a large-scale surveillance program across the state during the fall 2002 hunting season. More than 5,000 deer will be tested for CWD. For more information on this DNR program, check their web site at www.dnr.state.mn.us.

What should a person do if a deer that looks sick is seen or found?
Do not kill the animal. Contact the local conservation officer, area wildlife manager or DNR office. They are located at www.dnr.state.mn.us/contact/locator.html. The DNR is interested in investigating sick deer to protect the entire deer herd. Not all skinny, sick or unusual-acting deer have CWD. There are other diseases which may affect deer.

Transmission to Other Animals

How does CWD spread?
CWD is transmitted from animal to animal by direct contact with infected animals or highly contaminated habitat. The infectious agents, prions, are thought to be passed from infected animals in feces, urine or saliva. These prions survive in the environment for a long time.

What about deer and elk farming?
The shipment of farmed deer, elk and other cervids is regulated and monitored by the Minnesota Board of Animal Health.

Deer are eaten by many other animals in the wild. Could CWD spread to other animals like foxes, wolves, or birds?
Prions are usually specific to one type of animal. Susceptibility in other wildlife species is being researched. It is unlikely that CWD or a similar prion-disease would spread to foxes, wolves or birds.

Can livestock get CWD?
Cattle and other domesticated animals appear resistant to natural infection. There are no reported cases of natural transmission of CWD to livestock. Research is continuing in this area.

Can humans get CWD from eating venison?
Prions have never been found in muscle meat, even in infected deer. There is no evidence CWD can be transmitted to humans. The World Health Organization made this conclusion after reviewing available scientific information. The U.S. Centers for Disease Control has found no evidence that prion-related disease in humans occurs more often in hunters and consumers of wild game than in the general population. No disease in people has been found after 16 years of monitoring affected areas in Colorado.

Testing

How is CWD detected?
CWD is diagnosed through microscopic examination and testing of brain samples from harvested deer or elk.

Do meat processors or locker plants in Minnesota or other states test for CWD in deer?
Locker and processing plants in Minnesota and other states will NOT test deer for CWD. Testing is conducted only in specially equipped and certified laboratories.

Where can hunters have their deer tested for CWD?
After a deer is registered, hunters may take the deer or deer head for sampling to one of the 98 participating veterinary clinics in Minnesota. A list is available on the DNR web site at www.dnr.state.mn.us/mammals/deer/cwd.html. Contact the clinic listed in your area to determine the fee charged for this service. Samples collected will be sent by the clinic to the U of M Veterinary Diagnostic Lab for testing. Hunters will be notified of results by mail.

Who pays for the cost of the testing?
Hunters will be responsible for the cost of any testing that they request. The DNR will cover the costs of testing that is a part of their state sampling plan.

How soon can hunters expect testing results? Immediately or several days or weeks?
This will vary depending on the number of samples the laboratory receives. It takes approximately one week to conduct the analysis. If large numbers of samples are submitted, then it will take longer, perhaps several months, to deal with the backlog.

What should hunters do with the meat while they are waiting for laboratory results?
Store the meat and trimmings in food bags or containers in the freezer until the results are available. When you receive negative test results, bring the trimmings back to the processor for making into sausage. Ask for a separate batch of sausage with only the trimmings from your deer. However, most processing plants need a minimum amount to make a batch of sausage.

What if it's processed and then the results come back that the animal was contaminated. Must the meat be destroyed and how?
Presently decisions are being made on the proper disposal of meat from deer that test positive. More information will be made available once the proper methods are examined.

Processing

What steps are recommended for meat processors when handling deer and elk?
It is important to minimize handling of the brain, tonsils, spleen, spinal cord and lymph nodes. Meat should be processed without splitting the backbone. All cuts used in steaks and chops can be removed from the carcass as boneless cuts. One knife or handsaw should be designated for head removal. It is also important to ensure thorough cleaning and sanitizing of knives, saws, grinders and other meat-cutting tools. Meat trimmings should be inspected and all lymph nodes removed before grinding and sausage making. All equipment must be completely disassembled and all meat scraps removed before the equipment is used again. All parts should be washed with a detergent specifically designed for cleaning meat equipment. Equipment should then be rinsed with clean water, sanitized with a chemical sanitizer or water of 180 degrees Fahrenheit, and allowed to air dry.

Where can I locate a processor?
A list of official meat processing plants and custom meat processors is available on the Minnesota Department of Agriculture web site at www.mda.state.mn.us. However, not all of these processing plants process venison.

What if the locker plant mixes meat from several carcasses and one tests positive for CWD?
In general, mixing of trimmings is discouraged. The Minnesota Department of Agriculture's Meat and Poultry Inspection Section is advising meat processors to separately handle deer that has been sampled for CWD. This may delay the processing of the deer if you intend to have any sausage products made, but it is the only way that trimmings from a potentially contaminated deer will not be inadvertently mixed with other trimmings.

Consuming Venison

Is venison safe to eat?
Prions have never been found in muscle meat - even in infected deer. State officials are not recommending any general restrictions on consumption of deer meat. However, as a general precaution, it is recommended not to eat deer or elk brains, spinal cord, eyes, spleen, tonsils or lymph glands where prions are known to accumulate.

Where can I get venison from animals which tested free of CWD?
Minnesota has CWD monitoring available for deer and elk breeders. Harvested animals are routinely tested for CWD. Producers of herds that have actively participated in the monitoring program for three or more years can be quite confident that they are free of the disease. A list of producers participating in the program is available from the Minnesota Board of Animal Health.

Must restaurants only serve venison or other wild game that has been tested and certified free of CWD?
Restaurants are not allowed to serve hunter-harvested deer or elk. Most venison served in restaurants is red deer from New Zealand or other farmed herds that are closely monitored for CWD.

What about hunting groups that sponsor public wild game dinners?
The Minnesota Food Code allows the donation of hunted deer to non-profit organizations for public wild game dinners. There are specific restrictions that apply regarding donation requirements, processing, evisceration, and cooking temperatures. If you have questions about what meat products qualify and the additional requirements for food service, please contact the Minnesota Department of Health at (651) 215-0870.

Hunter Safety

How can hunters protect themselves?

• Do not harvest, handle or consume any wild animals that appear to be sick or very thin
• Wear heavy rubber or latex gloves when dressing carcasses
• Use knives and equipment dedicated to field dressing
• Remove loins as boneless cuts; do not split the backbone
• Minimize handling of brain and spinal tissues (do not saw or cut through the spine or skull, or the remove head last)
• Do not consume the brain, spinal cord, eyes, spleen, tonsils, or lymph nodes from deer and elk
• Wash hands and equipment thoroughly

Should I go hunting this year?
That is an individual decision. The CWD risk to Minnesota hunters is extremely small, if at all - especially if the protection recommendations are followed.

More Information

Where can I learn more about CWD?

• Minnesota Department of Natural Resources, www.dnr.state.mn.us
• Minnesota Board of Animal Health, www.bah.state.mn.us
• Minnesota Department of Agriculture, www.mda.state.mn.us
• U of M Center for Animal Health and Food Safety, www.cvm.umn.edu/cahfs
• Minnesota Deer Hunters Association, www.mndeerhunters.com
• Minnesota Elk Breeders Association, www.mneba.org
• United States Department of Agriculture at www.aphis.usda.gov
• Colorado Division of Wildlife at www.wildlife.state.co.us
• Wisconsin Department of Natural Resources, www.dnr.state.wi.us
• Nebraska Game and Parks, www.ngpc.state.ne.us/wildlife
• National Wildlife Health Center, U.S. Geological Survey, www.nwhc.usgs.gov
• Chronic Wasting Disease Alliance, www.cwd-info.org

Developed for Minnesota in cooperation with:

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