Washtenaw is now the 15th Michigan county where chronic wasting disease has been identified in the wild deer population, according to the Michigan Department of Natural Resources. An adult buck found acting ill in Salem Township recently tested positive for CWD.
The Michigan State University Veterinary Diagnostic Laboratory, which works with the DNR to identify CWD in Michigan’s wild deer herd, confirmed the CWD finding. The U.S. Department of Agriculture’s National Veterinary Services Laboratory, in Ames, Iowa, also confirmed the test result.
CWD is a fatal neurological disease that affects white-tailed deer, elk and moose. The disease is chronic, slow developing, and spreads slowly across the landscape. To date, CWD has also been detected in wild deer in the following Michigan counties: Clinton, Dickinson, Eaton, Gratiot, Hillsdale, Ingham, Ionia, Isabella, Jackson, Kent, Mecosta, Midland, Montcalm and Ogemaw.
Prior to focused CWD surveillance in Washtenaw County, voluntary sampling between 2016 and 2019 resulted in 824 deer tested. In 2021 and 2022, focused CWD surveillance efforts were conducted to gather additional samples, and 875 more deer were tested. While this is the first positive in Washtenaw County, 39 deer in neighboring Jackson County have tested positive for CWD, through combined DNR collections and direct hunter submissions to the MSU Veterinary Diagnostic Laboratory.
“The expansion of chronic wasting disease to Washtenaw County is consistent with the slow spread we’ve seen throughout Michigan,” said Chad Fedewa, acting DNR deer, elk and moose management specialist. “This case was identified thanks to a resident who saw a deer that appeared ill and reported it to us. Every piece of data is valuable in helping us make science-based decisions to support Michigan’s wildlife. We are grateful that Michigan residents value deer and stay engaged in this way.”
Residents can report wildlife observations, including possibly sick wildlife, at Michigan.gov/EyesInTheField. There are several CWD testing options available at locations throughout Michigan.
Testing background and strategy
After initial intensive testing near areas of the first CWD detections in the state, the DNR began a rotational approach to testing in 2021. A group of counties is selected each year, with the goal of eventually testing enough deer in every Michigan county for early disease detection. Management has the potential to be most effective when the disease is caught early.
In 2021 and 2022, the DNR focused on testing in areas of both the southwestern and southeastern Lower Peninsula. In 2023, the focus moved to the northern Lower Peninsula, and in 2024, testing focused on parts of both the northern Lower Peninsula and the Upper Peninsula.
In these areas, deer have been submitted through drop boxes, staffed check stations and participating deer processors and taxidermists. In the rest of the state, testing is available for a fee through direct submission by hunters to a cooperating USDA-approved diagnostic laboratory or through free self-sample shipping kits in counties where CWD has previously been detected.
All deer from counties with previous confirmed cases of CWD or bovine tuberculosis that are donated to the Hunters Feeding Michigan program also are submitted directly to the MSU Veterinary Diagnostic Laboratory for testing.
Samples for 2024 are still being processed. Once completed, analyses will help identify counties in need of additional CWD testing in 2025.
Since chronic wasting disease was first detected in wild deer in 2015, over 109,000 deer have been tested for CWD in Michigan. In total, more than 143,000 wild deer have been tested through DNR surveillance efforts that started in 2002, with 261 CWD-positive deer identified. In addition, since direct hunter submissions of deer to the MSU laboratory began in 2020, just over 3,000 submitted samples have yielded 55 additional confirmed positives.
Safety recommendations
To date, there have been no reported cases of CWD infection in people. However, as a precaution, the U.S. Centers for Disease Control and Prevention recommends that infected animals not be consumed as food by either humans or domestic animals.
Hunters should take precautions when field-dressing or processing a deer. This includes wearing rubber gloves, minimizing contact with the deer’s brain and spinal tissue, and washing hands with soap and warm water after handling any parts of the carcass.
Proper disposal of a deer carcass is critical to prevent the spread of chronic wasting disease. Deer carcasses and parts should go directly to a landfill or be disposed of through regular bagged trash pickup. Deer harvested from known CWD areas should never be disposed of on the landscape.
