Don't forget the bug spray - Jamestown Canyon virus detected in Michigan mosquito sample

Jamestown Canyon virus (JCV), a virus that can make people sick, was detected in a mosquito sample taken in Saginaw County.

JCV doesn't make most people sick, the Michigan Department of Health and Human Services said, but when it does make people ill, it can cause fever, headache, and fatigue. In rare cases, it can cause severe disease in the brain and/or spinal cord including encephalitis and meningitis.

These are the first mosquitoes found to be infected with any virus so far this year. 

Residents are also warned that mosquitoes can carry other illnesses, including eastern equine encephalitis (EEE) and West Nile virus (WNV).

"It only takes one bite from an infected mosquito to cause a severe illness," said Dr. Natasha Bagdasarian, MDHHS chief medical executive. "We urge Michiganders to take precautions, such as using an EPA-registered insect repellent when outdoors, avoiding areas where mosquitos are present if possible, and wearing clothing to cover arms and legs to prevent bites."

Six cases of JVC were reported in Michigan in 2021, and one case was reported last year.

Most cases of JCV happen in late spring through mid-fall. Illness can develop within a few days to two weeks following a bite from an infected mosquito.

"Mosquitoes may seem like a small nuisance, but they can spread deadly diseases like West Nile virus and eastern equine encephalitis through their bites," said Mike Philip, Michigan Department of Agriculture Rural Development (MDARD) Pesticide and Plant Pest Management division director. "Michiganders can help limit the risk of disease outbreaks by developing a mosquito prevention strategy to reduce pest populations."

Tips for preventing mosquito bites:

  • Apply insect repellents that contain the active ingredient DEET or other EPA-approved products to exposed skin or clothing. Always follow the manufacturer’s directions for use.
  • Wear light-colored, long-sleeved shirts and long pants when outdoors. Apply insect repellent to clothing to help prevent bites.
  • Maintain window and door screening to help keep mosquitos outside.
  • Empty water from mosquito breeding sites around the home, such as buckets, unused kiddie pools, old tires and other water-holding containers where mosquitos can lay eggs.

Tips for protecting animals:

  • Talk to a veterinarian about vaccinating horses against WNV and other mosquito-borne diseases.
  • Place livestock in a barn under fans (as mosquitos are not strong flyers) and pets inside the home during peak mosquito activity from dusk to dawn.
  • Use an insect repellant on animals that is approved for the species.
  • Eliminate 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.
  • Contact a veterinarian if an animal shows signs of illness.