Michigan reports 1st human Eastern equine encephalitis case since 2016

The Michigan Department of Health and Human Services (MDHHS) and Allegan County Health Department have confirmed an infection of Eastern equine encephalitis (EEE) in an Allegan County resident. The individual was hospitalized in late August with a neurologic illness.

This is the first human case reported in Michigan since 2016, when three people were infected.

EEE is one of the most dangerous mosquito-borne diseases in the U.S., with a 33 percent fatality rate. The disease can often leave survivors with lasting brain damage.

Mosquito-borne illness will continue to be a risk in Michigan until late fall when nighttime temperatures consistently fall below freezing. Michigan residents are reminded to protect themselves against mosquito bites.

“There is still plenty of mosquito season left in Michigan,” said Dr. Eden Wells, MDHHS chief medical executive. “When outdoors, Michigan residents are urged to take precautions to protect themselves and their families from mosquito bites including using mosquito repellent and wearing long pants and long sleeves.”

Horse owners should note that EEE can also cause neurologic illness in horses. However, vaccination can protect horses from infection with EEE.

EEE is a virus of birds that is spread by mosquitoes near swamps and bogs. Human cases are rare, with only a few cases reported each year in the U.S. People who become ill with EEE may experience fever, headache, chills and nausea. In some cases, symptoms may progress to inflammation of the brain, signaled by disorientation, seizures and coma.