LANSING — Michigan’s health authorities are warning of a suspected rare mosquito-born virus, Eastern equine encephalitis.

The Michigan Department of Health and Human Services (MDHHS) said a man in Barry County is suspected of having the virus and is now urging people in 11 Michigan counties —Barry, Clare, Ionia, Isabella, Jackson, Kent, Livingston, Mecosta, Montcalm, Newaygo and Oakland — to cancel or postpone outdoor events that take place at or after dusk.

The virus is contracted by the bite of an infected mosquito. Though rare, the disease, also known as Triple E, is one of the deadliest ones spread by mosquitos in the U.S. The virus is known to kill 33 percent of people who become ill with it. It also kills 90 percent of horses that contract it.

Twenty-eight cases in horses in 11 counties have been detected as of Thursday. The MDHHS has been conducting aerial treatments in the affected counties over the last few days.

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.

To reduce the potential for people to be bitten by mosquitoes, the MDHHS is encouraging local officials in the affected counties to consider postponing, rescheduling or canceling outdoor activities occurring at or after dusk, particularly activities involving children. To protect the public health, the recommendation applies until the first hard frost of the year.

Residents can take these steps to avoid mosquito bites:

• Apply 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.
• Wear long-sleeved shirts and long pants when outdoors.
• 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, old tires or similar sites where mosquitoes may lay eggs.
• Use nets and/or fans over outdoor eating areas.