In mid-September a free-ranging, white-tailed deer in Genesee County died from epizootic hemorrhagic disease, according to the Michigan Department of Natural Resources Wildlife Disease Laboratory and the Michigan State University Veterinary Diagnostic Laboratory. EHD is a viral disease, sometimes fatal, found in wild ruminants such as white-tailed deer, mule deer and elk.
The disease is transmitted by a type of biting fly called a midge. Infection does not always result in the disease. Signs of illness within infected animals are highly variable, ranging from none at all to extensive internal bleeding and fluid accumulation. There is no evidence that humans can contract the EHD virus.
Illness can come on suddenly and severely, but also can linger for weeks or months in a low-grade state. In severe forms of the disease, deer lose their appetite and fear of humans, grow progressively weaker, salivate excessively and finally become unconscious. Due to a high fever and dehydration, infected deer often seek water to lower their body temperature and to rehydrate, and then are found sick or dead along or in bodies of water.
“Although this has been a single deer death at this point, we are asking for hunters to look around as they hit the field to let us know if they find dead deer, especially any near water,” says Tom Cooley, DNR wildlife pathologist.
Deer deaths from EHD in Michigan have occurred sporadically since 2006. Prior to 2006, EHD outbreaks in Michigan occurred in 1955 and 1974. The estimated mortality has varied from 50 to 1,000 deer per year in the affected isolated areas. The largest die-off occurred in 2012, with an estimated loss of more than 12,000 deer. No cases of EHD were confirmed in the state in either 2014 or 2015, and minimal cases were reported in 2016.
There is no known effective treatment for, or control of, EHD in wild populations. The disease has been seen for decades in many areas of the United States.
Property owners or recreationists who discover dead deer should report it through the DNR’s sick or dead bird and mammal reporting form, available at michigan.gov/eyesinthefield, or call their closest DNR Customer Service Center.
For more information on EHD, visit mi.gov/wildlifedisease.