From the October 2013 Conservationist
Wildlife Health Corner
A Look at chronic Wasting Disease
By Dr. Krysten Schuler
First in a series of wildlife health-related topics.
Chronic Wasting Disease (CWD) is a fatal disease that affects deer, elk and moose. The name refers to the emaciated appearance of animals in the final stages of infection. Infected deer may also drool and wander aimlessly. CWD in deer and elk is similar to "mad-cow disease" in cattle. At this time there is no evidence that humans can be infected with CWD. To be cautious, however, public health officials recommend that people refrain from eating meat from any animal known to be infected with CWD, and for hunters to take precautions when field dressing animals in areas where CWD occurs. Check out DEC's website at www.dec.ny.gov/animals/86796.html#Human for tips on handling, processing and eating big game meat.
CWD is neither a virus nor a bacterium. It is transmitted by an infectious protein called a "prion" that causes holes to form in the brain. CWD is difficult to control in both wild and captive deer. Infected deer may appear perfectly healthy for more than a year. During that time, they can infect other deer directly or indirectly by shedding prions into the environment via their urine, feces and saliva. Once in the soil, prions may remain infectious for many years. No treatment or vaccines are available for deer, and deer are only tested after they die.
When it comes to CWD, we would be wise to recall Ben Franklin's adage, "An ounce of prevention is worth a pound of cure." This is because once the disease is established, little can be done to eradicate it, and new infections keep popping up. Currently, wild deer are infected in 18 states; in 13 of those, CWD has been found in captive deer or elk.
New York is the only state to have seemingly eliminated CWD in the wild. In 2005, CWD was detected on two captive deer farms in Oneida County. DEC immediately set up a "CWD Containment Area." With the assistance of NYS Department of Agriculture and Markets and USDA Wildlife Services, DEC began a $1 million operation to remove and test as many deer as possible from this area. Two infected wild deer were found near the captive deer farms. After seven years of intensive surveillance, no additional cases have been found. It appears that quick action may have removed infected deer before the soil was heavily contaminated with prions.
Other states haven't been as lucky. CWD was just discovered in Pennsylvania. In Wisconsin, CWD was first detected in wild and captive deer in 2002. Last year, 20% of adult bucks and 10% of adult does in Wisconsin were infected. We hope education and prevention measures will keep CWD-infected materials and animals out of New York.
Dr. Krysten Schuler is a wildlife disease ecologist at Cornell University's Animal Health Diagnostic Center.
Keep CWD Out of New York State
• If you see sick or strangely acting deer, contact your local DEC Wildlife Office (www.dec.ny.gov/about/50230.html) or call the Environmental
Conservation Officer Dispatch at 1-877-457-5680.
• Don't feed deer-concentrating deer at feeding sites increases the risk of disease transmission.
• Place your deer carcass remains in a plastic bag, and dispose of the bag in a landfill.
• If you have a successful deer or elk hunt in another state, bring back only the meat, cleaned skull cap, or taxidermy mount.
• Choose synthetic deer lures; real deer urine can contain infectious prions.