Bay County Building
515 Center Avenue
Bay City, Michigan 48708-5941

Jamestown Canyon Virus Detected in Bay County Mosquito

Contact: Rebecca Brandt, Mosquito Control Manager | Phone: (989) 894-4555

Routine disease surveillance conducted by Bay County Mosquito Control has detected this year’s first evidence of Jamestown Canyon Virus (JCV) in a mosquito from Kawkawlin Township. In response, control efforts will take place in the area to reduce adult and larval mosquito populations.

JCV is spread to people by the bite of an infected mosquito, with the majority of those infected showing no symptoms. While the threat of infection is low, initial symptoms can include headache and fatigue, and in rare circumstances neurological symptoms. Last year, 6 human cases were reported throughout the state of Michigan. JCV was last detected in Bay County in 2021.

The best way to prevent mosquito-transmitted illness is to reduce the number of mosquitoes around your home and take personal precautions to avoid mosquito bites. To further lessen the risk, follow these recommendations:

  • Avoid being outdoors when mosquitoes are most active, especially between dusk and dawn.
  • Wear long-sleeved shirts, long pants, and socks when outdoors.
  • Apply insect repellent containing DEET, picaridin, or oil of lemon eucalyptus according to label instructions. Consult a physician or visit the CDC website,, before applying repellents to infants.
  • Eliminate sources of standing water on property (i.e. wading pools, old tires, bird baths, containers) by dumping water when possible to prevent larvae from developing into biting adults.
  • Vaccinating horses for both West Nile virus and Eastern Equine Encephalitis is strongly recommended.

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