Health officials: EEE risk in Michigan not over

Mark Hicks
The Detroit News

Though cooler temperatures are arriving in Michigan, state health officials warn that the risk for exposure to the viral Eastern Equine Encephalitis still lingers in some areas.

“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 the Michigan Department of Health and Human Services. “Until we have several days of consistently freezing temperatures it is possible that mosquitoes can still be active in areas of our state.”

Most recent equine case occurred in Kalamazoo County and had an illness onset on Oct. 11, state said.

Since people can be infected with EEE from the bite of a mosquito carrying the virus, state officials urge residents to take precautions including limiting outdoor activities at or after dusk as well as checking weather reports.

Citing entomologists, mosquitoes do not fly when outdoor temperatures are below 50 degrees, but "if temperatures warm up into the 50s and 60s throughout the day, mosquitoes can reemerge," the department said in a statement Tuesday.

The most recent case of EEE in a horse was reported in Kalamazoo County and had an illness onset on Oct. 11, according to the release.

The area had opted out of the state's aerial spraying treatment between Sept. 30 and Oct. 7, said Lynn Sutfin, a spokeswoman for the health department.

"It is possible we could see additional cases in both animals and people," she told The Detroit News. "The risk is low, but it still exists."

EEE is considered among the most dangerous mosquito-borne diseases in the United States, with a 33% fatality rate in people who become ill, and leaving many survivors with physical and mental disabilities, health officials said.

So far, EEE has been confirmed in 10 residents in Barry, Berrien, Calhoun, Cass, Kalamazoo and Van Buren counties. Five people have died.

EEE has also been confirmed in 46 animals in 17 counties: Allegan, Barry, Berrien, Calhoun, Cass, Genesee, Eaton, Jackson, Kalamazoo, Kent, Lapeer, Livingston, Montcalm, Newaygo, St. Joseph, Tuscola and Van Buren counties.

Among those was a deer found to be the first confirmed animal case of EEE in Eaton County, the Barry-Eaton District Health Department said Tuesday.

People younger than age 15 and over age 50 are at greatest risk of severe disease following infection.

Symptoms 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. Permanent brain damage, coma and death also can occur in some cases, state authorities said.

Tips to protect against the virus:

  • Avoid being outdoors from dusk to dawn, when mosquitoes that carry the EEE virus are most active.
  • Apply insect repellents that contain the active ingredient DEET, or other U.S. Environmental Protection Agency-registered product to exposed skin or clothing
  • Wear long-sleeved shirts and long pants outdoors, and apply insect repellent to clothing to help prevent bites. 
  • Maintain window and door screening to help keep mosquitoes outside. 
  • Empty water from mosquito breeding sites around the home, such as buckets, unused kiddie pools, tires or similar sites where mosquitoes may lay eggs. 
  • Use nets and/or fans over outdoor eating areas. 

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