Skip to main content

State completes planned aerial treatment targeting 14 counties New EEE cases announced; Michiganders urged to continue taking precautions


CONTACT: Lynn Sutfin, 517-241-2112

LANSING, Mich. – Aerial treatment covering more than 557,000 acres targeting 14 counties has been completed to help combat Eastern Equine Encephalitis (EEE), the Michigan Department of Health and Human Services (MDHHS) announced today.

“In one year, we have had more human EEE cases confirmed than in the past decade,” said Dr. Joneigh Khaldun, chief medical executive and chief deputy for health for MDHHS. “We chose to conduct aerial treatment to protect the health and safety of Michiganders. We also continue to urge communities and residents to take precautions against mosquito bites as the risk of EEE remains until the first hard frost.”

This announcement comes as another case of EEE was confirmed in a Cass County resident and five additional cases were confirmed in horses in Jackson, Kent and Tuscola counties. The onset dates of illness for the Cass County resident and the horses were prior to aerial treatment beginning on Sept. 30. Treatment was conducted in portions of Allegan, Barry, Berrien, Calhoun, Cass, Jackson, Kent, Lapeer, Livingston, Montcalm, Newaygo, St. Joseph, Van Buren and Washtenaw counties. In addition, Fort Custer Training Center, which is in both Calhoun and Kalamazoo counties, was treated.

The decision to conduct aerial treatment was made based on the large number of EEE cases in both people and animals this year. EEE has been confirmed in 10 people, with four fatalities. Cases resided in Barry, Berrien, Calhoun, Cass, Kalamazoo and Van Buren counties. In addition, cases have occurred in 39 animals from 16 counties: Allegan, Barry, Berrien, Calhoun, Cass, Genesee, Jackson, Kalamazoo, Kent, Lapeer, Livingston, Montcalm, Newaygo, St. Joseph, Tuscola and Van Buren.

EEE is one of the most dangerous mosquito-borne diseases in the United States, with a 33 percent fatality rate in people who become ill and leaving many survivors with physical and mental disabilities. People can be infected with EEE from the bite of a mosquito carrying the virus.

Additional aerial treatment is not planned at this time as upcoming weather conditions are not favorable for this type of application. To be most effective, aerial treatment must be conducted when evening and overnight temperatures are at 50 degrees and above.

Although the weather is cooler, the mosquitos that spread EEE are still active. Mosquitoes were caught in traps set Oct. 1 in southwest Michigan. Residents should continue to protect themselves from mosquito bites by:

  • Avoiding being outdoors from dusk to dawn when mosquitos that carry the EEE virus are most active.
  • Applying insect repellents that contain the active ingredient DEET, or other U.S. Environmental Protection Agency-registered product to exposed skin or clothing, and always follow the manufacturer’s directions for use.
  • Wearing long-sleeved shirts and long pants when outdoors. Apply insect repellent to clothing to help prevent bites.
  • Maintaining window and door screening to help keep mosquitoes outside.
  • Emptying water from mosquito breeding sites around the home, such as buckets, unused kiddie pools, old tires or similar sites where mosquitoes may lay eggs.
  • Using nets and/or fans over outdoor eating areas.

More information is available at  

# # #