Eastern Equine Encephalitis, a deadly a mosquito-borne virus, has been detected for the first time this year in Michigan.

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The zoonotic disease, EEE, which is transferred by mosquitos to both animals and people, was found in an infected horse in Livingston County and in a mosquito pool in Barry County.

According to the Michigan Department of Agriculture, EEE is one of the most dangerous mosquito-borne diseases in the U.S.

EEE has a 90 percent fatality rate among horses that become ill and a 33 percent fatality rate among humans who become ill. Last year, Michigan experienced 41 cases of EEE in animals and four cases in humans.

The following steps are recommended for protecting animals:

  • Talking to a veterinarian about vaccinating horses against EEE.
  • Placing horses in a barn under fans (as mosquitoes are not strong flyers) during peak mosquito activity from dusk to dawn.
  • Using an insect repellant on the animals approved for the species.
  • Eliminating standing water on the property—i.e., fill in puddles, repair eaves, and change the water in buckets and bowls at least once a day.
  • Contacting a veterinarian if a horse shows signs of the illness: mild fever and stumbling, which can progress to being down and struggling to stand.

In humans, signs of EEE infection include fever, chills, body and joint aches. The virus can also cause severe encephalitis, resulting in headaches, disorientation, tremors, seizures, and paralysis. Permanent brain damage, coma, and death are possible in some cases.

To avoid mosquito bites, it's recommended:

  • Applying insect repellents containing the active ingredient DEET (or other U.S. Environmental Protection Agency-approved products) to exposed skin or clothing, and always following the manufacturer’s directions for use.
  • Wearing long-sleeved shirts and long pants when outdoors. Applying insect repellent to clothing to further 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 children’s pools, old tires, or similar sites where mosquitoes may lay eggs.
  • Using nets and/or fans over outdoor eating areas.

State officials say that monitoring for EEE will continue through the rest of the summer and fall. Mosquito-borne illnesses like EEE pose a risk in Michigan until nighttime temperatures consistently fall below freezing.

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