Chronic wasting disease likened to ‘wildfire’

Chronic wasting disease is like a wildfire burning across Wisconsin that soon will cause localized population declines in white-tailed deer – if it hasn’t already – experts told a review panel recently.

The disease is approaching 50 percent prevalence in bucks and 30 percent in does in parts of southern Wisconsin, according to data provided by the Department of Natural Resources.

Wisconsin is a hot spot that’s being eyed by wildlife managers throughout North America, especially in at least 20 states and two provinces where chronic wasting disease infects wild populations of the deer family.

So far, no CWD has been is known to persist in wild deer in Idaho or Washington.

However, three areas just outside of Yellowstone National Park have produced CWD-infected deer recently, including a mule deer killed by a Wyoming hunter recently in the Shoshone National Forest.

In Wisconsin, the disease has taken hold to the point that it likely will cause declines in deer populations, said Michael Samuel, a wildlife ecologist with the Wisconsin Cooperative Wildlife Research Unit.

“The fire is now in the brush and it’s going into the trees,” Samuel said. “From a management perspective, you’ve got to try to get out ahead of it to keep it from spreading.”

Experts from the National Park Service, universities and wildlife agencies have formed a CWD Response Plan Review Committee to

assess the state’s current plan, discuss research and disease management in Wisconsin and provide CWD recommendations for the next five years.

Chronic wasting disease is a contagious disease caused by abnormal prions. It is found in deer, elk and other cervids.

It has not been shown to cause illness in humans or livestock, but the World Health Organization and other health experts recommend venison from CWD-positive animals not be consumed.

The disease was first identified in Colorado in the 1960s.

It was first reported in Wisconsin in 2002. Forty-three of the state’s 72 counties are now considered “CWD affected.”

The state’s CWD Response Plan goal is to “minimize the area of Wisconsin where CWD occurs and number of infected deer.”

However, an internal DNR review acknowledged that the number of CWD-positive detections, and distribution of disease detections, has increased over the five-year time frame.

The review also said, “Funding limitations and social/political factors influenced the ability for the Department to fully implement the plan and effectively respond to CWD.”

Samuel used the wildfire analogy to describe CWD in Wisconsin.

“(In southern Wisconsin), you are in the burn scar,” he said. “It’s incredibly difficult to do anything once it reaches this stage.”

The panel presented data on studies in western states, where the disease has been found since the 1960s, of CWD-linked population declines in elk, mule deer and whitetails.

The experts also presented information that showed a relatively rare genotype in deer and elk is more resistant to CWD, but still susceptible to the disease. In addition, animals with the rare genotype display less “fitness for survival.”

Hopes for a CWD vaccine have yet to be fulfilled, the experts said.

During the public input session of the meeting, Simon Liegel, 32, expressed concerns about the impact of the disease and lack of regulations in place to deal with its spread.

“We think CWD is worse than is being reported,” said Liegel, who hunts on property in Sauk County. “We see sick deer and want to see more done about it.”