99¢ per month for 3 months
99¢ per month for 3 months

State health officials warn of uptick in deadly mosquito-borne illness

Christine Ferretti
The Detroit News

An uptick in cases of a deadly mosquito-borne illness is prompting health officials to urge residents to take precautions for themselves and their animals.

The number of confirmed cases of Eastern Equine Encephalitis, or EEE, in 2020 has more than doubled from the number of cases found by this time last year. The disease has been confirmed in 18 horses, including five over the Labor Day holiday weekend, in comparison with eight at the same time in 2019, according to the Michigan Department of Agriculture and Rural Development.

The illness, most prevalent in the late summer and early fall, likely will continue to pose a threat to humans and animals through mid-October, state officials warn. 

"We cannot state this strongly enough: horse owners and the general public need to take responsible, proactive steps to protect themselves and their animals from mosquito-borne diseases immediately,” said state veterinarian Nora Wineland. "If we ignore what’s happening, we run the risk of losing lives.”

In 2019, Michigan experienced one of the worst outbreaks of EEE ever documented, with 10 human cases, including six deaths, and 50 cases in animals from 20 counties. 

Last year's cases were confined to three counties; Barry, Kalamazoo and St. Joseph. This year, the cases have been discovered in eight counties: Barry, Clare, Isabella, Kent, Mecosta, Montcalm, Newaygo and Oakland. 

Symptoms of EEE include the sudden onset of fever, chills, body and joint aches. Severe encephalitis, resulting in headache, disorientation, tremors, seizures and paralysis or death can occur.

Wineland said it's unclear whether the dramatic increase in cases is due to a lapse in vaccinations or a higher prevalence in the state's mosquito population.

“We strongly urge Michiganders to take precautions against mosquito bites,” added Joneigh Khaldun, chief medical executive and chief deputy for health at the Michigan Department of Health and Human Services. “Mosquito-borne diseases can cause long-term health effects in people, even death."

For the safety of horses and other animals, including sheep and goats, state officials recommend placing livestock in a barn under fans from dusk to dawn, eliminating standing water and contacting a veterinarian to obtain vaccines or report symptoms of illness. 

To protect themselves, Michigan residents should apply insect repellents that contain the active ingredient DEET, wear light-colored, long-sleeved shirts and long pants when outdoors and empty water from mosquito breeding sites around the home, the state said.

For information about mosquito-borne diseases, go to