When chronic wasting disease was discovered in a wild Norwegian reindeer two years ago, officials took quick action. They culled the entire reindeer herd in Nordfjella — 2027 animals in all. Eighteen of those reindeer were found to be infected.
The Norwegian government had a clear goal in mind: to save the deer herd and prevent CWD from becoming established in their country. Vidar Helgesen, minister of climate and environment, stated, “We must do everything we can to prevent the disease from spreading to other areas of wildlife or other deer species.”
This is a vastly different response to CWD than we have seen in Wisconsin.
CWD was first detected in Wisconsin in 2001 when three deer tested positive in Iowa and Dane counties. The next year, the Department of Natural Resources expanded its testing program and found 205 positives out of 40,351 wild deer. Despite the DNR scaling back its testing program in 2007, occurrence of the disease has been increasing steadily. Last year, 595 positive samples were found out of 9,779 deer tested.
To date, CWD has been detected in 53 counties throughout the state. It is likely, however, that the disease is more widespread because of insufficient testing. Last fall in La Crosse County, for example, the DNR tested only 82 deer.
Reading “Wisconsin’s Chronic Wasting Disease Response Plan: 2010–2025,” one comes away with the impression of a vast gap between the potential harmful consequences of CWD and the recommended strategies for averting those consequences.
The report begins with a bang: “All available evidence indicates that CWD has the potential for significant, negative impacts on the future of deer hunting in Wisconsin.”
An infectious agent known as a prion causes CWD. It is a misfolded protein particle that operates differently than viruses or bacteria. Prions do not trigger an immune response. Chemicals, radiation and extreme heat will not kill them. They appear to be highly contagious and can accumulate in the environment where they persist indefinitely. There is no known treatment. Infection is always fatal.
CWD is presently limited to cervids (deer, elk, moose, caribou), yet there is some evidence that the disease could jump the species barrier, similarly to what happened with “mad cow disease” in Britain in the 1990s. That is why the World Health Organization recommends “no part of an animal known to have CWD be consumed by humans.”
The DNR report concludes the section on Principles of CWD and Disease Management with these words: “There is no evidence that CWD will ‘disappear’ or ‘run its course’ on its own in the absence of management.”
Such words imply the necessity of drastic measures. Yet the strategies in the report are anything but drastic. They consist mainly of continued monitoring and research in the hopes that some solution will come along in the future.
To get an idea of how cynical the report is, consider this recommended strategy: “Continue to cooperate with the Department of Health Services to maintain the registry of persons known to have consumed venison from CWD positive deer.”
The facts are that in 2017 only 3 percent of hunters statewide and 8 percent of hunters in the Southern Farmland Zone where CWD is concentrated tested their deer for contamination. So neither the DNR nor the DHS have any idea how many people in the state have consumed infected venison, and until testing is greatly expanded, they cannot have a meaningful registry.
Moreover, a negative test does not guarantee that venison is CWD-free nor can we be confident that the disease has not already infected some humans.
A recent study on the threat of CWD to humans in the current issue of “Transboundary and Emerging Diseases” states: “Future discovery of CWD transmission to humans cannot be entirely ruled out on the basis of current studies, particularly in the light of possible decades‐long incubation periods for CWD prions in humans.”
Here are the facts.
- Without significant reduction of the deer herd, CWD will continue to progress throughout the state, eventually affecting every county in Wisconsin.
- People should not consume venison from infected deer, and there will soon be no area of the state free from possible infection.
- Testing every deer harvested during the hunting season is impractical, due to the high cost of the tests and the inconvenience to the hunter.
Unless we stop the expansion of CWD by drastically reducing the deer herd, hunters will soon have to choose between eating possibly infected venison or giving up hunting.
All this leaves me wondering how long deer hunting will continue to be part of Wisconsin culture.
Norway developed their response to containing CWD in part by observing the disaster slowly unfolding in Wisconsin.
The question we face now is this: Are we too late to avert disaster?