By Chris Comer, Ph.D., SCIF Director of Conservation
Deer and elk hunters in North America have been bombarded recently with more news items about a topic they would probably just as soon forget: chronic wasting disease (CWD). It started in the fall and winter with announcements that this potentially devastating disease had been detected in Quebec and in several new counties in Tennessee. In early February, the Chronic Wasting Disease Transmission in Cervidae Study Act was introduced to Congress. This legislation provides funding to states and universities for research addressing management of CWD. Shortly after that, there was a video clip from Pennsylvania in which claims were made that researchers in Louisiana had discovered a cure for CWD. Finally, a series of articles appeared in the mainstream media in mid to late February about “zombie deer disease” and threats to human health from CWD.
At this point, most deer hunters in North America are aware of the basics regarding CWD. It is an infectious, debilitating disease that affects white-tailed deer, mule deer, elk, moose and caribou in 26 states, four Canadian provinces, and isolated areas in South Korea and Norway. It was first described in Colorado, is believed to be 100% fatal in affected animals, and has no known cure. It is caused by misfolded proteins called prions that also cause bovine transmissible spongiform encephalopathy (Mad Cow Disease) and scrapie in sheep. While CWD is not currently causing widespread reductions in deer populations, that potential certainly exists; this combined with human health concerns and impacts on hunter participation mean that CWD represents one of the most important threats to hunting and wildlife management in North America.
SCI and SCI Foundation have published several articles and other communications over the past year, but with the latest media outbreak it seemed appropriate to revisit this issue. The news from Louisiana sparked hopeful interest from hunters and wildlife managers that an answer was in sight to cure CWD. These claims are based on a theory proposed by Dr. Frank Bastian at Louisiana State University that CWD is caused by minute bacteria called spiroplasmas and not, as generally thought, by misfolded proteins known as prions. If the causative agent for CWD was a bacterium, then the disease would be amenable to treatment by traditional means such as antibiotics and vaccines. Unfortunately, this theory has been proposed for several years and multiple attempts by other researchers have not verified Dr. Bastian’s findings. Thus, the overwhelming preponderance of the evidence, and the overwhelming majority of researchers and wildlife managers, identifies prions as the direct causative agent for CWD. Solving CWD is not likely to be that easy.
In contrast, the articles about zombie deer disease caused many hunters and non-hunters increased levels of fear regarding hunting and particularly consumption of meat from deer harvested in CWD areas. Although there is no evidence CWD can infect humans, the similar bovine spongiform encephalopathy jumped across species to infect humans that consumed meat from infected cows. There have been reports of people in the U.S. contracting the disease after eating venison, but these have been investigated thoroughly and no causal link was found. The Centers for Disease Control states there is currently no evidence that CWD can cross the species barrier into humans. Nonetheless, there is justifiable concern about the potential for CWD to affect humans and most agencies recommend that hunters not eat meat from infected animals. Essentially all states with CWD offer deer hunters the opportunity to submit their deer for testing—we recommend that hunters in affected areas get their deer tested before consuming the meat.
Research into the ecology and management of CWD will be critical to future management efforts and the future of deer hunting in North America. Safari Club International Foundation recognizes this and supports Federal legislation that will provide funding for these efforts. We also recognize the importance of CWD to SCI and our members. The Foundation and our Conservation Committee are currently in the process of developing a strategy for supporting research and management efforts related to CWD and we count on the support of SCI’s hunter-conservationists to help us make an impact on this important issue.