Epizootic Hemorrhagic Disease Confirmed in Deer of Mecosta County
Michigan Department of Natural Resources (DNR) officials have confirmed cases of Epizootic Hemorrhagic Disease (EHD) impacting white-tailed deer populations across several counties in Michigan during 2025, with the bulk of reports coming from southern regions.
Notably, a west Michigan DNR wildlife biologist, Pete Kailing, reported finding dead deer believed to have succumbed to EHD near Horsehead Lake last weekend and in the Martiny Chain of Lakes earlier this week. Current observations indicate one deceased deer at each site, although further assessment is pending.
Understanding EHD and Its Effects on Deer Populations
Experts from the Michigan DNR emphasize that EHD is a viral illness transmitted by infected midges, which are small biting flies. The virus cannot be transmitted directly between deer, requiring the insect vector to spread the disease.
While EHD can be fatal to individual white-tailed deer, deer populations typically demonstrate resilience and recovery following outbreaks. The disease tends to emerge prominently in late summer to early fall, often coinciding with environmental conditions such as a wet spring followed by a hot, dry summer—an ideal climate for midge proliferation.
Guidance for Hunters and the Public
Wildlife officials urge hunters and residents who encounter sick or deceased deer to report these sightings promptly. Reports can be submitted via the Michigan DNR’s Eyes in the Field reporting tool on their website or by contacting a local DNR Customer Service Center.
- EHD affects primarily white-tailed deer populations in Michigan.
- Transmission occurs via biting midges; direct deer-to-deer spread does not occur.
- There is no evidence that EHD poses a risk to humans, pets, or other wildlife species.
- The midge population dies off after the first frost, halting virus transmission.
- Deer populations generally recover from EHD outbreaks with minimal long-term impact.
Biological and Ecological Context
The viral agent behind EHD causes hemorrhaging and severe internal damage in infected deer, often leading to rapid mortality. This disease plays a natural role in regulating deer populations, though spikes in mortality may cause short-term changes in local herd dynamics.
Because midges breed in moist environments, weather patterns strongly influence the scale of EHD outbreaks. This year’s reported cases align with established patterns seen during similar climatic conditions in past decades.
Additional reporting and sources from: EHD: Dead deer found in Mecosta County
