Eastern Equine Encephalitis

  • 2020 EEE Outbreak Information

    As of Sept. 22, EEE has been confirmed in 32 animals in 13 counties – 30 equine and two deer. To date, there is one confirmed human case in Barry County. There is an EEE vaccine available for horses, but not for people. Protecting horses with approved EEE vaccines is an important prevention measure.

    In an effort to prevent spread of Eastern Equine Encephalitis (EEE), MDHHS has announced plans to conduct aerial mosquito control treatment in certain high-risk areas of Michigan. To prevent the loss of life and protect public health, MDHHS has determined a targeted aerial treatment plan is necessary. When there are high rates of animal infections, humans are just as at risk.

    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. People can be infected with EEE from one bite of a mosquito carrying the virus. Persons younger than age 15 and over age 50 are at greatest risk of severe disease following infection. More than 25 percent of the nation’s EEE cases last year were diagnosed in Michigan. The risk of bites is highest for people who work and play outdoors in affected areas.

  • EEE 2020

    Update for Thursday, September 24

    Aerial treatment to help prevent the spread of Eastern Equine Encephalitis resulted in nearly 27,000 acres being treated in Blocks 4-4 and 10-2 on Wednesday, Sept. 23. Nearly 462,000 acres have been treated to date.

    At this time, no additional treatment is planned. MDHHS will continue to monitor the situation and treatment zones could be added if new cases are found and aerial treatment would be effective to reducing risk of exposure.

    The most up-to-date information will be posted here at Michigan.gov/EEE.

    MDHHS hotline for general EEE questions: 888-535-6136 
    (Monday through Friday, from 8 a.m. to 5 p.m.)

    FAQ :  Eastern Equine Encephalitis and Aerial Treatment 

    Spanish | Arabic

    State EEE Treatment Blocks

    Michigan County Treatment Zones

    MDARD Emergency Rule Amending R 285.637.11

    Why can I not opt-out of aerial treatment this year?

    2020 Press Releases


    Arbovirus Daily Update, including Eastern Equine Encephalitis in Michigan (Updated September 25, 2020):

    2020 Weekly Arbovirus Surveillance Summary