MADISON, Wis. — State health workers confirmed the first cases of the West Nile Virus in Wisconsin for 2024.

What You Need To Know

  • This week, a healthy blood donor from Washington County tested positive for West Nile. So did a dead bird in Chippewa County

  • Mosquitos pick up the virus from infected birds and humans can get the virus if bitten by an infected mosquito. Humans cannot pass West Nile to each other

  • According to the Centers for Disease Control and Prevention, 80% of people infected with the West Nile Virus do not develop any symptoms; 20% develop flu-like symptoms. About 1 in 150 people develop severe illness

  • Ronesha Strozier with Public Health Madison and Dane County urged people to protect themselves by using insect repellent, wearing long sleeves and pants when outdoors, making sure windows and doors have screens on them, and eliminating any standing water

This week, a healthy blood donor from Washington County tested positive for West Nile. So did a dead bird in Chippewa County.

“The blood donor never developed any symptoms,” said Ryan Wozniak, a communicable disease supervisor with the Wisconsin Department of Health Services. “So, it's not considered a confirmed or probable case.”

Mosquitos pick up the virus from infected birds and humans can get the virus if bitten by an infected mosquito. Humans cannot pass West Nile to each other.

According to the Centers for Disease Control and Prevention, 80% of people infected with the West Nile Virus do not develop any symptoms; 20% develop flu-like symptoms. About 1 in 150 people develop severe illness.

“We see people who have infections of their central nervous system,” Wozniak said. “So, that can result in swelling of the brain and spinal cord and paralysis and coma. In very rare cases, even death.”

Ronesha Strozier with Public Health Madison and Dane County urged people to protect themselves by using insect repellent, wearing long sleeves and pants when outdoors, making sure windows and doors have screens on them, and eliminating any standing water.

“Do you have any kiddie pools that are unattended that you leave water in? Any flowerpots, or just buckets lying around your backyard or your front yard? You want to tip those over,” Strozier said.

Tom Thao is an avid fisherman. Lake Monona is closest to his home, but he travels throughout the state for good fishing. He said he’s noticed more mosquitos lately.

“The thing is, when we get heavy rain, it creates a breeding environment for mosquitoes, like puddles and things like that, where it's very moist,” Thao said.

Thao said he listens to the experts, so he doesn’t have to forego fishing.

“Usually when I’m outdoors, I'm wearing long sleeves,” he said. “I put on a repellent and what not.”

Public Health Madison Dane County said it is treating mosquito breeding grounds in Dane County. Learn more, here.