Summary of the Association of Fish & Wildlife Agencies’ Best Practices to Prevent CWD
The Association of Fish & Wildlife Agencies (AFWA), which is the authoritative voice for wildlife management agencies across North America, recently published a comprehensive document identifying the best practices for CWD prevention, surveillance, and management. Thirty experts on CWD, wildlife, and wildlife management used the best available science to provide policy options on a number of topics. Hunters, agencies, and legislators should use this document to better understand CWD and control its spread.
AFWA’s policy recommendations are aimed at agencies responsible for providing oversight on wild and captive cervids. AFWA understands and highlights the importance of communicating and working with all relevant stakeholders prior to policy change or implementation. However, hunters and captive-cervid farmers can choose to follow all of the recommended best management practices covered in this report to help limit the spread of CWD even if their state, province, or territory has less stringent policies. By doing so, they can be sure that they are playing an important role in the fight against CWD.
In section one of the report, AFWA identifies risk factors for CWD transmission and how to reduce the risk. This section is summarized below:
Movement of Live Cervids
The first identified risk factor is the movement of live cervids by both wildlife agencies and the captive cervid industry. The report states that circumstantial evidence suggests the movement of infected live cervids between facilities likely resulted in CWD infections among wild cervid populations in places like Saskatchewan, Nebraska, South Dakota, and Wisconsin. The lack of a validated, highly sensitive antemortem (live-animal) test for CWD prevents knowing whether or not a cervid is infected before it is transported. AFWA’s policy recommendations range from a total ban on anthropogenic (human-assisted) movement of live cervids to prohibiting movement from CWD-endemic areas. Until there is a validated, highly sensitive antemortem test available, all anthropogenic movement of live cervids presents a risk for CWD spread.
Movement of Hunter-Harvested Carcasses
AFWA recognizes the risk of continued disease spread through the movement of infected carcasses. The carcass of a CWD-positive cervid has prions in various tissues, with a high concentration in the brain, spinal cord, lymph nodes, and tonsils. Therefore, moving a CWD-positive carcass to different geographic areas introduces the risk of further CWD transmission. AFWA provides example policy recommendations that vary by carcass part and by state, province, and territory (e.g., some parts may be prohibited from all states, provinces, territories regardless of whether or not they have detected CWD). As best practice, harvested cervid carcasses should not be imported from any other state, province, or territory unless all high-risk parts are removed. AFWA states that this would still allow for importation of “cut/wrapped meat, deboned meat, cleaned skulls or skull cap with no brain material, shed antlers, hides, canine teeth, and finished taxidermy mounts.” All removed parts should be properly disposed of to prevent other animals from coming into contact with CWD prions. Carcass disposal recommendations can be obtained by contacting the relevant wildlife agency or by visiting the agency's website. Following these best practices will reduce the risk of CWD spread.
Transportation and Use of Cervid Urine and Reproductive Tissues
AFWA has also identified the sale and use of products that contain cervid urine as a potential risk factor. Cervid urine is collected in captive cervid facilities and is sold in various products for use as a scent lure. CWD prions have been detected in the urine of infected cervids, suggesting that the use of these products could be a risk for disease spread. The AFWA report highlights the lack of existing regulations within the cervid urine business and expresses concern that saliva and feces, which could contain higher doses of infectious CWD prions, can be accidentally mixed with urine during collection. Subsequent use of these products from CWD-infected cervids could serve as a risk for indirect disease spread as they enter the environment. Following best management practices, AFWA states that products containing natural cervid urine should not be used, and synthetic products could serve as an effective alternative. Comparably, AFWA highlights concern that reproductive tissues, such as embryos and semen, could be a source of CWD infections, and their use for selective breeding warrants regulatory consideration. Reducing the movement and use of reproductive tissues would remove the risk of CWD transmission occurring via that pathway.
Baiting and Feeding
AFWA identifies baiting and feeding as a risk factor for CWD transmission, as it can lead to artificial congregation of cervids. Promoting artificial congregation via baiting and feeding can introduce infected and susceptible animals. Even if infected animals don’t come in direct contact with susceptible animals through baiting and feeding, they can shed prions in their saliva, urine, and feces, which can later infect animals that are feeding in the same spot. The best management practice recommended by AFWA on this topic is the prohibition of baiting and feeding for all wild cervids. At the very least, the prohibition of baiting and feeding in areas with known CWD cases is a good way to prevent increased disease transmission.