Michigan’s Department of Natural Resources (DNR) is tracking a deadly deer disease that has been confirmed in 11 counties in the state.
The Michigan counties where EHD was identified are Barry, Berrien, Branch, Calhoun, Cass, Hillsdale, Kalamazoo, Kent, Ottawa, St. Joseph, and Van Buren.
According to the DNR, epizootic hemorrhagic disease (EHD) is carried by a fly called the midge, which bites deer. Once bitten, the deer experiences acute hemorrhaging.
It’s speculated that EHD has contributed to deer die-offs since the 1890s through case history research.
It was first identified in 1955 when hundreds of white-tailed deer succumbed to EHD in Michigan and New Jersey.
It primarily emerges in white-tailed deer and occasionally in mule deer and pronghorn antelope.
Fortunately, EHD hasn’t contributed to large-scale decreases in population, though there was a “significant outbreak” in 1974.
Because of its high mortality rate, EDH can significantly reduce the population of deer in regional areas.
In 2012, there was an outbreak in 30 counties, and in 2021, 24, before this current outbreak in 11 counties.
The disease can’t be passed from deer to deer; the midge is the only vector, the DNR said.
Epizootic outbreaks, which occur in large numbers of deer, typically do not recur, while die-offs of small numbers occur annually at a predictable rate, which is what is classified as enzootic, the DNR said.
Deer develop symptoms within seven days after being bitten.
The DNR said a common characteristic is the disease’s “sudden onset.”
“Deer initially lose their appetite and fear of humans, grow progressively weaker, often salivate excessively, develop a rapid pulse and respiration rate, and fever (affected animals frequent bodies of water to lie in to reduce their body temperature) and finally become unconscious,” DNR said. “Hemorrhage and lack of oxygen in the blood results in a blue appearance of the oral mucosa, hence the name ‘bluetongue.’”
Hemorrhaging takes place in the heart, liver, spleen, lung, intestinal tract, and kidney.
After a period of eight to 36 hours, deer go into shock before dying in the prostate position.
The disease is diagnosed through “characteristic signs and lesions” and case history research.
The DNR said EHD doesn’t affect the edibility of venison, and there’s been no evidence that humans can contract the disease from being bitten or venison consumption.
Also, pets and wildlife can’t be infected from being bitten or eating EHD-infected deer carcasses.
There’s no effective method of treatment or control for the disease other than theoretical proposals for oral vaccines administered during “a supplementary winter-feeding program.”
However, the DNR said this is “presently impossible, impractical and unwarranted.”
