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MDHHS encourages communities to consult local weather forecasts when scheduling evening activities


CONTACT: Lynn Sutfin, 517-241-2112

LANSING, Mich. – The Michigan Department of Health and Human Services (MDHHS) recommends communities consult local weather forecasts to determine whether or not to host outdoor activities occurring at or after dusk, due to the possible continuing risk of Eastern Equine Encephalitis (EEE). Recent cooler temperatures are favorable to reducing exposure to EEE, however, its threat may still exist in certain areas of the state.

According to entomologists, mosquitoes do not fly when outdoor temperatures are below 50 degrees. However, if temperatures warm up into the 50s and 60s throughout the day, mosquitoes can reemerge, continuing the risk of EEE. MDHHS urges residents to continue taking precautions against mosquito bites until their community experiences multiple days of hard frost.

“Unfortunately, there isn’t a specific temperature or other scientific literature to positively say the threat is over,” said Dr. Joneigh Khaldun, chief medical executive and chief deputy for health for MDHHS. “Until we have several days of consistently freezing temperatures it is possible that mosquitoes can still be active in areas of our state.”

The most recent equine case of EEE occurred in Kalamazoo County and had an illness onset on Oct. 11, illustrating the ongoing risk.

Michiganders should continue to protect themselves from mosquito bites by:

  • Avoid being outdoors from dusk to dawn when mosquitoes that carry the EEE virus are most active, particularly when temperatures at dusk are above 50 degrees.
  • Applying insect repellents that contain the active ingredient DEET, or other U.S. Environmental Protection Agency-approved 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.

EEE is one of the most dangerous mosquito-borne diseases in the United States, with at least a 33 percent fatality rate in people who become ill. People can be infected with EEE from the bite of a mosquito carrying the viruses. Persons younger than age 15 and over age 50 are at greatest risk of severe disease following infection.

In total, EEE has been confirmed in 10 people, with five fatalities. Cases resided in Barry, Berrien, Calhoun, Cass, Kalamazoo and Van Buren counties. In addition, EEE been confirmed in 46 animals from 17 counties: Allegan, Barry, Berrien, Calhoun, Cass, Eaton, Genesee, Jackson, Kalamazoo, Kent, Lapeer, Livingston, Montcalm, Newaygo, St. Joseph, Tuscola and Van Buren.

Signs of EEE infection include the sudden onset of fever, chills, body and joint aches which can progress to a severe encephalitis, resulting in headache, disorientation, tremors, seizures and paralysis. Anyone who thinks they may be experiencing these symptoms should contact a medical provider. Permanent brain damage, coma and death may also occur in some cases.

More information is available at  


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