Weather Forecast


Editorial: Don’t dismiss West Nile threat from mosquitoes

Remember when mosquitoes and deer ticks were just minor annoyances?

Not anymore. Tick-borne Lyme Disease and mosquito-borne West Nile virus reached lakes country a few years ago.

Minnesota’s first case this season of West Nile virus was reported Thursday. State health officials said the man, from Murray County in southwest Minnesota, became ill with West Nile fever earlier this month and is recovering.

This time of year is a high-risk season for West Nile virus, and it’s time to protect yourself from mosquitoes by using repellents and taking other steps to avoid mosquito bites.

The species of mosquito that transmits the virus to humans is most abundant in July and August, according to David Neitzel, a state Health Department epidemiologist specializing in diseases carried by mosquitoes. Using mosquito repellents at dusk and dawn, when the little critters are at their hungriest, can keep people safe from West Nile virus, which is a potentially severe disease.

How worried do you need to be?

About one out of 150 people bitten by a West Nile virus-infected mosquito will develop central nervous system disease (encephalitis or meningitis). About 10 percent of people with this severe form of infection die from their illness, and survivors can suffer from long-term nervous system problems.

Most people bitten by infected mosquitoes develop West Nile fever, the less severe form of disease, or fight off the virus without any symptoms. Illness from West Nile virus can occur in residents throughout Minnesota and among all age groups. But the risk is greatest in western and central counties, which typically have the greatest number of Culex tarsalis mosquitoes, the primary mosquito carrier of the virus in Minnesota.

West Nile cases have been reported in this area since 2002, and the number of cases surged in the first few years, then declined, according to data from the State Health Department.

But it appears to be back on the upswing. Last year there were 70 cases, and one death, attributed to West Nile virus across the state. Otter Tail County had one case and Clay County had four cases. No cases were reported last year in Becker, Hubbard, Mahnomen and Clearwater counties, but there were cases in 34 Minnesota counties in all. Yellow Medicine County in the southwestern part of the state had the most, six cases.Becker County had a case in 2008 and Hubbard County had one in 2009. Last year appears to be the worst year since 2007, when West Nile was widespread in the state. Clay County reported 11 cases that year, and Becker County reported five cases. In all, there were 101 cases in 41 counties that year, according to the Health Department. The year before that, there were 65 cases in 39 counties, including Becker, Clay, Hubbard, Otter Tail and Wilkin.

So this area is definitely in the target zone: Elderly people or people with weakened immune systems face the highest risk of developing more severe or even fatal illness from a West Nile virus infection. Wear mosquito repellent or stay out of feeding range completely at dusk and dawn.

Forum News Service

The Forum Communications News Service is the premier news wire service covering the Upper Midwest, including the Dakotas, Minnesota and Wisconsin. In addition to breaking and enterprise news, we offer a wide variety of sports, features, business, agriculture, outdoors and opinion content. For more information about the services we offer or to discuss content subscriptions, please contact us.