Tests initiated by the Minnesota Department of Natural Resources confirmed that a wild deer near Caledonia in southeastern Minnesota’s Houston County died from epizootic hemorrhagic disease. EHD is a viral infection that members of the deer family are susceptible to.
Although not confirmed, EHD is suspected in the death of other deer in the region.
Houston County is the second county where wild deer have contracted EHD. Earlier this month, the disease was confirmed in four wild deer in the St. Stephens area of Stearns County in central Minnesota. Additional deer in a three-square-mile area in that county are suspected of having died from the virus.
"The DNR will continue to monitor the situation in these counties, sampling suspect deer as opportunities arise," said Michelle Carstensen, DNR wildlife health program group leader. "Sampling of multiple deer deaths may become necessary if the disease appears to be in more areas."
Previously, the Board of Animal Health confirmed that two farmed deer near Rushford in Houston County died from EHD.
People who find multiple dead deer should report them to the nearest DNR area wildlife office. Cervid farmers should contact their veterinarian if they’re concerned about EHD in their herd.
EHD can dramatically reduce a local deer population in the short-term but has a relatively small impact on the overall deer population.
Minnesota has avoided the disease in wild deer until this year, but EHD is common in the Midwest. Wisconsin, Nebraska, Iowa, Illinois, Michigan and Ohio report EHD mortalities almost every year.
"EHD has circulated in the southern United States for decades and outbreaks in deer there are typically mild," Carstensen said. "Movement of the EHD virus to the northern United States, where there is little history of previous exposure, can result in severe outbreaks with high localized mortality."
No management actions are available to combat the disease.
The first known instance of EHD-infected deer in Minnesota occurred in October 2018, when testing confirmed it in six captive deer in Goodhue County.
EHD is spread by a biting insect called a midge. The disease is not a threat to humans or animals outside the deer family. Even so, people should not consume deer that appear to be sick or in poor health.
A female midge, commonly called a noseeum, picks up the virus when it bites an infected host and transmits the virus by biting another host. The disease cannot be transmitted deer-to-deer and does not remain on the landscape.
The disease is seasonal and most often occurs during drought-like conditions during late summer and early fall. Frost will kill the virus and midge that carries it, ending the potential infection period.