| Chronic Wasting Disease (CWD)
What Every Taxidermist Should Know About Chronic Wasting Disease (CWD) (Updated 7/21/08) What is Chronic Wasting Disease? CWD is a member of the TSE (Transmissible Spongiform Encephalopathy) family of diseases that includes BSE (Bovine Spongiform Encephalopathy or Mad Cow Disease in cattle), CJD (Creutzfeldt-Jakob disease in humans), and Scrapie in sheep and goats. It was first recognized in Colorado deer and elk in 1967. The specific cause of CWD is believed to be an abnormal prion (protein infectious particle) that is found in the brain, central nervous system and some lymphoid tissues of infected animals. It causes death of brain cells, and on a microscopic level, holes appear in the brain tissue. What animals get CWD? CWD has been diagnosed in members of the cervid family and has been found in white-tailed deer, mule deer, black-tailed deer and hybrids thereof, as well as elk and moose. CWD has not been shown to be transmissible to humans or traditional livestock. However, it is recommended that meat from CWD-positive animals not be consumed. It has been diagnosed in deer, elk and moose in 14 states and 2 Canadian provinces: Colorado3 Illinois2 Kansas3 Minnesota1 Montana1 Nebraska3 New Mexico2 New York3 Oklahoma1 South Dakota3 Utah2 West Virginia2 Wisconsin3 Wyoming3 Alberta, Canada3 Sasckatchewan, Canada3 1Captive Cervids 2Wild Cervids 3Both Captive and Wild Cervids How is CWD transmitted? Scientists believe that CWD is transmitted through animal-to-animal contact and through food and soil contaminated with bodily excretions including saliva. Contaminated carcasses or high-risk carcass parts may also spread disease indirectly through environmental contamination. What are the signs of CWD? Animals infected with CWD show a general loss of body condition, most notably weight loss. Excessive drinking, urination, salivation, and drooling are common in the late stages of the disease. Behavioral changes such as repetitive walking patterns, droopy ears, incoordination, a wide-based stance, and listlessness also accompany CWD infection. Some animals lose their fear of humans and predators. The onset of these signs may not become evident for years. There is no known cure and this disease is always fatal. What actions have been taken to prevent the spread of CWD? The movement of high-risk carcass parts (brain, spinal cord, lymph tissues) is a potential avenue through which CWD could be spread from infected areas. Investigations in New York indicate that in that state the infection could have been spread by a taxidermist who accepted specimens from CWD-positive states, allowed rehabilitated fawns access to the taxidermy workshop and spread potentially infections curing salt waste as a fence line week killer on his deer farm. Several states, including Pennsylvania, have developed regulations to prohibit the importation of high-risk carcass parts from CWD endemic states. As of April 1, 2006 Pennsylvania’s importation ban prohibits the importation of high-risk carcass parts from Colorado, Illinois, Kansas, Nebraska, New Mexico, New York (CWD containment area only), South Dakota, Utah, West Virginia (Hampshire County only), Wisconsin, Wyoming and the Canadian provinces of Alberta and Saskatchewan. Pennsylvanians hunting in CWD-positive areas should get their animals tested and should leave high-risk carcass parts in the area where the animal was hunted. Specific carcass parts where the CWD prion (causative substance) concentrates are: head (including brain, tonsils, eyes and retropharyngeal lymph nodes); spinal cord and smaller nerves; spleen; upper canine teeth, if root structure is present; any object or article containing visible brain or spinal cord material; unfinished taxidermy mounts or brain-tanned hides. |