Are mosquito-borne diseases becoming more common in Minnesota?

MINNEAPOLIS — Whether you’ve been eaten alive or spared this summer, health officials say don’t let your guard down when it comes to mosquitoes just yet.
Minnesota Department of Health epidemiologist supervisor Elizabeth Schiffman says mosquito-borne diseases peak at the end of summer into early fall when there is a larger mosquito population and they’ve had more time to circulate viruses.
“I don’t think it’s something where want people to panic about of course, but definitely knowing that the risk is there and this time of year is definitely the highest risk time,” Schiffman said.
In Minnesota, six mosquito-borne diseases are on the radar of health officials: West Nile virus, La Crosse encephalitis, Jamestown Canyon virus, Western equine encephalitis, Eastern equine encephalitis and St. Louis encephalitis The most common is the West Nile virus.
“We see cases every year, but some years we have a lot of activity and some years not so much,” Schiffman said.
Most who get infected have no symptoms but for some, the West Nile virus can be severe or deadly.
“It’s actually the most serious of the mosquito-borne diseases that we have in the United States,” Schiffman said.
West Nile virus can cause flu-like symptoms and is deadly for about one-third of people who develop it. While EEE has been found in Wisconsin, no human cases have been reported in Minnesota.
“We in Minnesota are in the western edge of the range for that virus, but we have mosquitoes that can spread it. But we just don’t see a lot of activity with it here,” Schiffman said.
Schiffman says a warming climate could mean a longer mosquito season and a greater spread of disease.
“Things are changing and viruses are changing,” she said. “People move so it’s very possible. You know, West Nile virus wasn’t a virus we had in the United States 25 years ago.”
The best way to protect yourself is prevention.
The threat typically diminishes by the end of the month or early October. The first hard frost will get rid of the mosquitoes, too.