MADISON, Wis. -- As warm evenings become more frequent in Wisconsin so do the number of mosquitoes and the accompanying threat of West Nile virus.

In Wisconsin, the risk of being bitten by an infected mosquito is the greatest from July to early September, according to health care officials. It only takes one mosquito bite to transmit the potentially lethal virus, WISC-TV reported.

Doctors said that 80 percent of people who get the infection would have no symptoms at all. Others will have a mild form of the illness, but about 1 percent will get severe symptoms, which typically lead to encephalitis.

"The only way to prevent West Nile virus is to prevent is to prevent mosquito bites. You do that in two ways," said Dr. John Hausbeck of from the Department of Public Health. "First, keep the mosquito from landing on you and biting, and the other is to reduce populations of the mosquito."

Hausbeck said that the public could protect itself by wearing insect repellent with 20 percent DEET, socks, long-sleeves, and long pants when outdoors.

He said that people should avoid areas of standing water where mosquitoes breed and congregate, WISC-TV reported.