Treatment is currently unavailable for this disease. While there has been partial preliminary clinical success in vaccination of white-tailed deer in New York, and further research in Canada, no vaccine has been proven effective thus far. Some have speculated as to the potential for natural immunity in cervids, similar to that of sheep with scrapie, the TSE that infects domestic sheep and goats, there has been no compelling evidence to suggest natural immunity exists. If natural immunity were genetically conferred on individuals, management to select for them in wild populations would prove exceedingly difficult, although it might be an avenue for protection in captive cervid operations.
Although there is no treatment or vaccination for CWD, a number of states and provinces have adopted management practices aimed at reducing prevalence and limiting transmission. These are not specific to free-roaming or captive deer, but applicable to all cervids at risk of CWD. We outline a few of these practices, their benefits, possible problems, and implementation.
Density Management-
This practice focuses on limiting the spread of the disease by lowering animal density to levels where transmission would be minimal. The prescribed density often reflects scientific estimates of natural (non-human influenced) densities. This may be achieved through lethal or non-lethal removal of animals, or habitat modification. The removal of large numbers of animals can reduce densities in wild or captive populations, or can involve the total removal of animals from a captive cervid facility. Although this strategy is likely the most effective at preventing transmission after CWD has been introduced into a region, other states have indicated difficulty maintaining hunter-performed culling programs over long periods of time (> 5 years). This practice could be implemented to some effect. The larger the area managed, the more effective at minimizing disease transmission the practice will be.
Bait and Feed Limitation/Removal-
Reducing the availability and frequency of supplemental feeds or bait serves to limit sites where cervids congregate in large numbers, and helps limit transmission. While this solution can be effective, it also may affect situations where hunting business relies on the consistent appearance of game animals at bait sites. This practice is extremely easy to implement, although in some ways unpalatable to the public. One possible modification is that landowners frequently move bait and feeding sites to prevent infectious agent buildup in the soil, and perhaps discontinue baiting and feeding during some times of the year.
Selective Removal-
When an animal displaying clinical symptoms of CWD is spotted, it is lethally removed from the herd and disposed of safely to minimize exposure to other individuals. This maximizes the number of deer in the herd while removing those that appear infected. This method would not remove animals before they became able to transmit the disease. Research suggests that this model has the potential to significantly reduce disease prevalence, provided that infected animals can be identified and removed. Such coverage may prove impractical in large, sparsely populated areas of Texas.