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 or water sources 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 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 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. Pennsylvania's high-risk carcass parts ban does not limit the importation of: meat, without the backbone; skull plate with attached antlers, if no visible brain or spinal cord material is present; tanned hide or raw hide with no visible brain or spinal cord material present; cape, if no visible brain or spinal cord material is present; upper canine teeth, if no root structure is present; or finished taxidermy mounts.
There is a lot of information flying around right now, some accurate, some not, regarding the high risk parts ban. Let me give you the Department of Agriculture's intent and the facts of the ban.
The intent is to prevent material, which is most likely to contain the CWD prions (brain & spinal cord) from being brought into PA and discarded in woods, fields, etc., after processing. After decomposition the prions can remain, contaminate vegetation, water, etc., and infect susceptible cervids in PA. As a result, we are banning heads and backbones BUT NOT antlers, skull caps and cleaned capes and hides. In other words, the antlers and skull caps can be brought back (as long as they have no visible brain or spinal cord tissue on them) along with boned meat, cleaned eye teeth or finished taxidermy mounts. If someone brings a whole head that has been harvested in a banned state to a taxidermist, we ask that they contact their regional PDA office to report it. The taxidermist is allowed to remove the antlers with skull cap attached, but cleaned of all visible brain and spinal cord material. He/she is allowed to cape the animal and keep it and the hide, again as long as all visible brain and spinal cord tissue is removed. The brainstem (obex) and retropharyngeal lymph nodes should be harvested by the taxidermist if he/she is a trained CCT (Certified CWD Technician) or arrangements can be made with the PDA regional staff for them to harvest these tissues so that CWD testing can be done and the hunter notified of CWD status for meat consumption decision purposes. The regional PDA staff is charged with collection of the banned materials so that they can be properly destroyed. This is to help protect your PA deer herd and helps stop the spread of CWD. If a whole animal from a CWD infected state is brought back to PA and processed, either by yourself or a meat processor, the remaining carcass parts after butchering / processing should be bagged and kept separate. You must notify your local PDA office and they will collect them for incineration. PDA urgently requests that taxidermists do not allow any high risk parts originating from any cervids from any state be disposed of through a rendering service. Our concern is that this allows for the possibility of prions being introduced to animal food channels. Although CWD is not known to be infectious to other species at this time, this is a new disease and much research on these matters has not yet been done. This is very important. To Summarize: If an intact head is brought from a state named in the ban and presented to a taxidermist, PDA's ban DOES NOT PREVENT MOUNTING OF THAT HEAD. What it does require of the taxidermist is: Reporting to the PDA regional office. Preparing the mount so that skull cap & antlers, cape & hide are preserved free of brain and spinal cord tissue. Brain stem and retropharyngeal lymph nodes are saved for testing. Make the banned materials available for PDA regional staff to collect for disposal. We know this is all new and there are bound to be situations that have not been anticipated. Our desire is to make this as clear and unambiguous as possible for all concerned. As of today, CWD has been detected in wild and captive herds of deer and / or elk in Colorado, Illinois, Minnesota, Montana, Nebraska, New Mexico, New York, South Dakota, Utah, West Virginia (Hampshire County), Wisconsin, and Wyoming, as well as in the Canadian provinces of Saskatchewan and Alberta. Oklahoma and Kansas are not listed in PDA's high risk parts ban because CWD has not been detected in wild cervid population. There is no practical way to test live animals for CWD, nor is there a vaccine.
If you have any questions about CWD please call your regional PA Dept. of Ag. office or the Bureau of Animal Health or Dan Snyder from the PA Taxidermy Association. Feel free to copy this letter and give to your customers, local meat processors, sportsman's groups, and sporting goods stores. The more folks that understand how this disease can effect our PA deer herd and what they can do to help prevent its spread the better. THANKS!!