MDHHS: 1st mosquito-borne virus cases found in Oakland, Macomb residents

The first mosquito-borne virus cases of 2023 have been detected in Oakland and Macomb county residents, according to the state's health department Friday.

Two residents tested positive for Jamestown Canyon virus (JCV), a mosquito-borne virus, according to the Michigan Department of Health and Human Services. They are the first human arboviral illness cases identified in the state this year.

Symptoms typically include a high fever, confusion, muscle weakness and a severe headache. More serious complications include neurological illnesses such as meningitis and encephalitis.

JCV and other mosquito-borne viruses are transmitted through the bite of a mosquito that has gotten the virus by feeding on an infected animal. Most people who contract the virus have no symptoms of illness, but some may become ill two to 14 days after the bite of an infected mosquito.

Michigan residents are being urged to take precautions to prevent mosquito bites, especially in August and September  The MDHHS is reminding residents that the best way to protect against all mosquito-borne illnesses including JCV, West Nile virus (WNV) and Eastern Equine Encephalitis virus (EEE) is to prevent mosquito bites.

Mosquito pools from Bay, Saginaw, and Washtenaw counties have tested positive for JCV this summer. WNV has been found in mosquitoes collected in Kalamazoo, Wayne and Washtenaw counties.

The risk for mosquito-borne illness rises throughout the state over the course of the mosquito season, peaking in August and September.

"It only takes one bite from an infected mosquito to cause a severe illness, so we advise using insect repellent and wearing long-sleeved shirts and long pants when outdoors during times when mosquitoes are active," said Dr. Natasha Bagdasarian, MDHHS chief medical executive "It’s a good idea to take extra precautions during peak mosquito-biting hours, which are from dusk to dawn."

Precautions include:
Using EPA-registered insect repellents with one of the following active ingredients: DEET, picaridin, IR3535, oil of lemon eucalyptus or para-menthane-diol and 2-undecanone. Follow the product label instructions and reapply as directed.

Don’t use repellent on children under 2 months old. Instead dress your child in clothing that covers arms and legs and cover crib, stroller and baby carrier with mosquito netting.

Wearing shoes and socks, light-colored long pants and long-sleeved shirts when outdoors.

Making sure doors and windows have tight-fitting screens. Repair or replace screens that have tears or other openings.

Using bed nets when sleeping outdoors or in conditions with no window screens.

Eliminating all sources of standing water that can support mosquito breeding around your home, including water in bird baths, abandoned swimming pools, wading pools, old tires and any other object holding water once a week.

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