Amanda Forrester / news@whmi.com

Officials are reporting Michigan’s first cases of epizootic hemorrhagic disease in deer for 2025.

The DNR Wildlife Health Section, Michigan State University Veterinary Diagnostic Laboratory and the Southeastern Cooperative Wildlife Disease Study said the virus was found in deer from Eaton, Jackson, Van Buren and Washtenaw counties.

Further detections will be posted on the DNR’s EHD webpage, linked below, as samples are submitted from other counties.

EHD, a viral, sometimes fatal disease, periodically affects white-tailed deer in the state. It is transmitted through the bite of either an infected biting fly or midge. Deer cannot transmit the disease directly to one another.

There is no evidence that humans, household pets or other wildlife in Michigan contract the virus. Venison harvested in areas that have EHD is safe for consumption, officials said. It’s not recommended to eat any visibly-sick deer.

“In past years when we’ve confirmed EHD, it has typically affected only one or few counties,” Brent Rudolph, deer, elk and moose management specialist for the DNR Wildlife Division, said. “Occasionally, localized outbreaks have been detected in a dozen or more counties, including as many as 30 in 2012.”

The disease typically affects deer in late summer and early fall. Officials said outbreaks can be more severe in years that have a wet spring followed by a hot, dry summer. The first frost kills the midge population and stops disease transmission.

Deer suspected of contracting the disease or dying from it should be submitted through the DNR’s Eyes in the Field online system. Due to a high fever and dehydration, deer infected with EHD often seek water.

Visible symptoms include appearing lethargic, disoriented, lame or unresponsive. Officials said these can also be symptoms of other illnesses or injuries. Infected deer may show a bloody discharge from the nose and mouth, a swollen or blue-tinged tongue and swelling of the eyelids and neck or head.

EHD can only be confirmed through testing by a qualified laboratory.

Further testing isn’t necessary once it’s confirmed in a county, but the DNR encourages suspected cases to be reported. The data allows them to track an outbreak’s full extent.

Outbreaks haven’t been shown to significantly impact deer populations long-term, though deer mortality can be intense in small geographical areas. Local impact may continue for a few years.

Not every deer in an outbreak area will get it, nor is it a death sentence for those infected.

“Deer that survive epizootic hemorrhagic disease develop immunity to the virus, and outbreaks are rarely seen in the same area in consecutive years,” Rudolph said.

(photo credit: DNR)