Michigan health officials confirm state’s first EEE-positive mosquitos this year

BAY COUNTY, Mich. – Health officials said they have identified the first mosquitos to test positive for Eastern Equine Encephalitis (EEE) in Michigan this year.

Members of the Michigan Department of Health and Human Services said mosquitos recently collected in Bay County tested positive for EEE. There have been no confirmed human cases, but the virus can be transmitted from a single mosquito bite.

“This testing information confirms the virus is here in mosquitos in Michigan,” MDHHS chief medical executive Dr. Natasha Bagdasarian said. “EEE is one of the most dangerous mosquito-borne diseases in the United States, with a 33% fatality rate in people who become ill.”

People under 15 years old and over the age of 50 are at greatest risk of getting severely ill due to EEE.

The virus can cause sudden fever, chills, and body joint aches. Those symptoms can progress to severe encephalitis, headaches, disorientation, tremors, seizures, and paralysis.

In severe cases, permanent brain damage, comas, and death are possible, officials said.

Anyone who thinks they might have EEE or any of these symptoms should call a doctor.

More than 600 mosquito pools were tested in Michigan from the start of 2023 to the end of June.

There were no human cases of EEE in 2022, but three horses and one bird were killed. One human case of EEE was confirmed in 2021, four cases were confirmed in 2020, and 10 were confirmed in 2019.

Two people were killed by EEE in 2020, and six were killed in 2019.

How to prevent mosquito bites

Here’s more information from MDHHS on how to prevent mosquito bites:

• Apply insect repellents that contain the active ingredient DEET or other EPA-approved products to exposed skin or clothing. Always follow the manufacturer’s directions for use.

• Wear light-colored, long-sleeved shirts and long pants when outdoors. Apply insect repellent to clothing to help prevent bites.

• Maintain window and door screening to keep mosquitos outside.

• At least once a week, empty water from mosquito breeding sites around the home, such as buckets, unused children’s pools, old tires and other water-holding containers where mosquitos can lay eggs.

How to protect horses

Horses are especially vulnerable to EEE, with a 90% fatality rate when they become ill. The disease is not spread by horse-to-horse or horse-to-human contact.

MDHHS recommends the following to protect horses:

• Talk to a veterinarian about vaccinating horses against EEE and other mosquito-borne diseases.

• Place horses and other livestock in a barn under fans during peak mosquito activity (from dusk to dawn).

• Use an insect repellant on animals that is approved for the species.

• Contact a veterinarian if an animal shows signs of illness.