Chronic wasting disease continues to spread in white-tailed deer in Wisconsin and other states, highlighted by two findings this month.
On April 11 the Department of Natural Resources confirmed the first positive CWD test result in a wild deer in Waushara County. The 3-year-old buck was found dead in early February in the town of Wautoma, according to the agency.
And April 5 the Indiana Department of Natural Resources announced the first detection of CWD in Indiana. That deer was a hunter-killed buck taken in LaGrange County in the north of the state.
Indiana had been the only state in the Midwest without a CWD detection.
Neither finding was a surprise given the trajectory of the disease which over recent decades has steadily increased in geographical distribution and prevalence rates.
The spread of the fatal deer disease is linked to ineffective strategies and procedures in place to control it and, in many jurisdictions, decisions by legislators and wildlife officials.
Since CWD has not been documented to cause illness in humans or livestock most state agencies and elected officials have enacted measures to only monitor its spread.
It’s also not yet known if it can cause a population decline in whitetail herds with high recruitment rates such as seen in much of Wisconsin. Results are pending of a multi-year DNR research project on the effects of CWD in a southern Wisconsin study area.
Should CWD ever be found to affect the health of humans or livestock or wipe out deer populations, wildlife managers and elected officials will be forced to shift management tactics.
Chronic wasting disease is a fatal, infectious nervous system disease of whitetails, mule deer, moose, elk and other members of the deer family. It belongs to the family of diseases known as transmissible spongiform encephalopathies or prion diseases, including Mad Cow Disease and scrapie.
Deer can spread the disease to other deer through close contact. Deer can also pick up the infective prion from the environment.
The disease spreads relatively slowly across the landscape and often takes more than one year for an infected animal to show symptoms.
It was first documented in 1967 at a research facility in Colorado. The first CWD detections in wild and captive deer in Wisconsin were announced in 2002.
As of this month, CWD has been detected in free-ranging cervids (deer or other members of the deer family) in 33 states and four provinces and in captive cervid facilities in 19 states and three provinces, according to the U.S. Geological Survey’s National Wildlife Health Center.
The Centers for Disease Control and Prevention and Wisconsin Department of Health Services recommend meat from CWD-positive animals not be consumed by humans.
With regard to management, Wisconsin is among states that ceased aggressive measures to try to control CWD and is simply monitoring the disease as it spreads throughout the state.
For the 2023 testing year in Wisconsin, 1,586 deer were CWD-positive out of 17,314 analyzed, or 9.2%, according to the DNR. The number and the percentage of positives were highest since the DNR began testing for the disease in 1999.
As a result of the CWD finding in Wautoma, the DNR and the Waushara County Deer Advisory Council plan to host a public meeting. At the meeting, DNR staff will provide information about CWD in Wisconsin and local testing efforts within Waushara County. No date has been set; the DNR is expected to announce details in the near future.
The Waushara County finding will not trigger any new hunting or other regulations as a deer baiting and feeding ban was in place due to a CWD finding in an adjacent county.
State law requires the DNR enact a three-year baiting and feeding ban in counties where CWD has been detected, as well as a two-year ban in adjoining counties within 10 miles of a CWD detection. If additional CWD cases are found during the lifetime of a baiting and feeding ban, the ban will renew for an additional two or three years.
The Indiana finding was expected as CWD had previously been detected in its surrounding states. The April 5 announcement came from a deer near the border with Michigan.
The Indiana DNR asked the public to help with surveillance by reporting sightings of sick or dead deer as well as submitting harvested deer for testing during deer hunting season.
“Through increased awareness and testing, we can work to monitor CWD within Indiana’s deer population,” an agency spokesman said in a statement.
Research is being conducted to produce CWD test kits hunters could use in the field; it’s unknown when a viable product will be available. Trials are also underway on the potential risks from CWD to human health and livestock. And the captive cervid industry is working to selectively breed genotypes of deer that offer more resistance to the disease.
Wisconsin continues to offer free CWD testing to hunters. For more, visit dnr.wi.gov.
