KALAMAZOO, Mich. — It's a problem unique to Michigan: bovine tuberculosis found in whitetail deer. The disease was first found in Michigan deer in the mid 1970s.
Bovine tuberculosis is a serious disease caused by bacteria attacking the nervous system. There are several types of the disease, but bovine tuberculosis impacts many different mammals in the wild.
Michigan is the only state in the nation with bovine tuberculosis found in white tail deer, making the state a hotbed of research for the disease.
In deer, the disease causes lesions on the rib cage, a visual clue of infection. Officials with the sate Department of Natural Resources warn, however, that a little less than half of infected deer show visual signs. That makes bringing deer to check stations vitally important in confirming the infection.
The DNR said the northeast lower peninsula is the core area for bovine TB. Specifically, the four corners area of Montmorency, Alpena, Oscoda, and Alcona counties has remained the hot spot.
"In 452, which is our core area, in 2017 the prevalence increased from 2 percent to 3 percent, and that's something that we'll watch because we really get concerned when we see a multiple-year trend of that prevalence increasing," said Emily Sewell, a wildlife health specialist with the state Department of Natural Resources.
Bow season for deer hunting started Oct. 1, and deer check stations are open across Michigan. Four deer have tested positive for the disease this year, all from the core area.
The counties surrounding the core area also will be monitored closely by the DNR in the years to come. While even more rare, there were still some deer that tested positive in these neighboring counties. They will be closely watched to ensure the disease doesn't spread significantly outside of the four core counties.
The DNR also hopes to sample at least 300 deer in three other zones outside of the core area, in Kalamazoo, Barry, Calhoun and Ottawa counties. This was due to findings earlier this year, in which a bovine TB strain found in an Ottawa County cattle herd was traced back to Kalamazoo County. The cattle, which came from a bovine TB-infected herd in Indiana, had spent time at a Kalamazoo County farm before making it to Ottawa County. The DNR wanted to sample deer in a 10-mile radius from these sites to ensure no deer were infected.
Sewell reminded hunters that they are the eyes in the field.
“Hunters are still our primary tool for deer management and helping to control this disease and the surveillance," Sewell said. "So we really rely on our hunters and appreciate their efforts.”
The DNR deer check stations across West Michigan include:
Van Buren County: Wolf Lake Fish Hatchery
Allegan County: Plainwell Customer Service Center
Cass County: Crane Pond State Game Area
Kent County: Tim´s Processing
For additional information and more check stations across the state, the DNR has an interactive map online.