West Nile virus has been detected in two locations near Grand Rapids, Michigan, marking the first confirmations for the 2026 season in the state.
The Kent County Health Department said on Tuesday that routine mosquito surveillance found the virus in mosquito samples from the Grand Rapids ZIP code 49504 and the Wyoming ZIP code 49519.
This is the first detection for the season in the state.
The Michigan Department of Health launched its surveillance program in late May, testing 227 mosquito pools and reporting no known cases of animal- or human-borne mosquito-borne diseases.
The most effective way to prevent West Nile virus or other mosquito-borne illnesses is to prevent mosquito bites, state health officials said. Those steps include discarding, regularly flushing or draining old tires, tin cans or bird baths that can hold small pools of water, as that might create a space where insects can breed. People should also be aware that mosquitoes are most active at dawn and dusk.
“When used as directed, EPA-registered insect repellents are proven safe and effective,” the health department also said.
Treatment for West Nile virus
Michigan health officials say there is no vaccine to prevent West Nile virus in humans, and the known treatment focuses on relieving symptoms such as fever.
In some severe cases, patients with West Nile virus will need hospital care.
The Centers for Disease Control considers West Nile virus cases to be a “nationally notifiable condition.” There were 2,076 human cases confirmed during 2025, of which 50 were in Michigan.