There is no known strategy for effectively eliminating or slowing down the spread of CWD. All attempts to slow down the spread and prevalence of CWD are experimental in nature and therefore should be approached in a systematic, hypothesis-based scientific approach to applied management. Results from the experiments should be used to evaluate the hypothesis and adapt strategies if necessary. Using this approach would produce insights valuable to Alberta in the long-term, and potentially helpful to other jurisdictions that have CWD on the landscape.
“After 20 years of involvement in almost every aspect of CWD, I tend to be more philosophical than scientific in my perspective of this disease. I reflect on human arrogance, which demands a solution to every problem, but knows not the consequences of the solution. I question our empathy for healthy, sentient creatures when our only management solution seems to be a bullet. I despair at how ineffectual human intervention is once a disease takes hold in wildlife. Lastly, I wait to see a comprehensive cost-benefit analysis of current and proposed management efforts to control or eradicate CWD.”
Terry J. Kreeger, DVM, PhD retired as the State Wildlife Veterinarian with the Wyoming Game and Fish Department. Boone and Crockett Club, Fair Chase Magazine, Summer 2017.
"Results of this paper agree with conclusions that were obtained in Potapov et al. [6] about the significant role of sexual segregation and transmission within deer bachelor and family groups. In spite of the observed higher prevalence in males compared to females, our analysis shows that infected females produce more secondary infections than males due to their higher survival rates and transmission to males during mating. This may mean that the major source of CWD spread may be female groups. If this disease pattern is close to reality, then male-only management harvest may reduce the number of infected individuals, but cannot stop the transmission of infection.
Estimates of model parameters related to the herd-reduction program in 2006–2008 show that removal of infected deer is efficient among females but not among males. The reason may be behavioural differences between males and females. The latter tend to stay within smaller areas, and the cull may cover a significant proportion of an infected female’s home range and stop the transmission among females. Indeed, Cullingham et al. [25] found that female deer harvested with 2 km were more genetically related than males, and CWD-positive deer were more likely to be related. In contrast, males move within larger areas than females [22,26], and if males contact individuals over a larger area they will increase the spatial spread of the disease.
On the other hand, the conclusions about the efficiency of culls in females (but not on the number of secondary infections left by females) are based mainly on the decline in estimated female prevalence between 2006 and 2007–2008. Therefore additional data are necessary to come to a more definite conclusion."
2015 paper from Alex Potapov, Evelyn Merrill, Margo Pybus, and Mark A. Lewis - Sadie Jane Ryan, Editor
"Two characteristics of this disease make it particularly difficult to manage. First, empirical data indicate CWD transmission can occur at low deer densities; this attribute necessitates high levels of population reduction or complete removal of deer in order to eradicate the disease. Second, evidence indicates infectious prions persist in the environment for years."
"Management programs should be seen as experiments and must be designed to monitor outcomes, such as changes in deer densities, alterations in the age structure of populations, changes in disease transmission rates, size of the affected area, changes in disease prevalence, etc. These monitoring programs must be consistent and long-term in order to determine which management strategies work and which do not.
Although CWD management experiments are being implemented in other parts of North America, they need to be replicated in order to validate the results. The slow moving nature of the epidemic makes management “failure” difficult to detect and therefore monitoring programs must be carefully designed and well funded. Management programs should be adaptive in order to take advantage of new information as it becomes available." –
Bollinger, Dr. Trent; Caley, Dr. Peter ; Merrill, Dr. Evelyn; Messier, Dr. Fracois; W. Miller, Dr. Michael; Samuel, Dr. Michael D.; and Vanopdenbosch, Dr. Emmanuel , "Expert Scientific Panel on Chronic Wasting Disease" (2004). Canadian Cooperative Wildlife Health Centre: Newsletters & Publications. 19.
“Despite significant advances in our understanding of CWD over the past 40 years, there is still little published information on effective management (Miller and Fischer 2016, Uehlinger et al. 2016). While some of the aforementioned strategies have been modeled, field data on efficacy are limited or lacking.”
“Best Management Practices for managing CWD prevalence in infected populations should include the following….
• Develop and implement regulations to minimize the possibility of spreading CWD by controlling the transportation of carcasses and potentially infective carcass parts between hunt areas and across state boundaries. Through regulation, ensure the head and all portions of the spinal column are either left at the site of the kill or disposed of in an approved manner.”
“It follows that a coordinated, adaptive management approach would provide a path forward for CWD management. Adaptive management would allow for strategic application and evaluation of experimental CWD suppression strategies whereby the data gathered would then be used to develop improved strategies. This approach is not to be confused with simple trial and error; rather it is a systematic, hypothesis-based and scientific approach to applied management (Walters 1986, Walters and Holling 1990, Williams 2009).”
Association of Fish and Wildlife Agencies, Washington, D. C., “AFWA Technical Report on Best Management Practices for Prevention, Surveillance, and Management of Chronic Wasting Disease”, 2018
“This highlights the need for management strategies that include realistic goals, can be applied for extended time periods, and have sufficient public and constituent acceptance. Because eradication is not feasible at this time, management for CWD control will require ongoing commitment by wildlife managers and the public. It follows that programs focused solely on agency culling are unlikely to be viable as a sustained management approach in Western jurisdictions.”
“The underlying adaptive management framework includes a systematic approach for learning from management outcomes over time. This approach is essentially equivalent to the scientific method of hypothesis formulation and hypothesis testing. Results are used not only in evaluating the hypothesis, but also to gather new data directing future management.”
Western Association of Fish and Wildlife Agencies. 2017. Recommendations for Adaptive Management of Chronic Wasting Disease in the West. WAFWA Wildlife Health Committee and Mule Deer Working Group. Edmonton, Alberta, Canada and Fort Collins, Colorado, USA.