DETROIT (AP) - Two Detroit residents died after being infected with West Nile virus. They the first in the state killed by the mosquito-borne illness this year, the Michigan Department of Community Health said yesterday.

The victims were a 68-year-old man and a 68-year-old woman, department spokesman T.J. Bucholz said. He did not know when they died.

The state has confirmed 29 cases of West Nile virus this season, Bucholz said. A Muskegon County woman tested positive for West Nile virus before she died in late July, but officials later ruled out the virus as the cause of the 37-year-old woman's death.

"West Nile virus is a tricky illness," Bucholz said. "It's possible to have West Nile virus and never know you have it."

Michigan had 62 reported human cases and four deaths from West Nile in 2005.

West Nile season usually peaks in late August and doesn't end until November. "We're actually hoping for an early frost so the mosquito population will have a die-off," Bucholz said.

Nationally, 1,634 cases of human West Nile virus, including 52 deaths, were reported to the federal Centers for Disease Control and Prevention as of Sept. 12. For all of 2005, there were 3,000 reported cases and 119 deaths nationwide.

People can cut down on contact with mosquitoes by wearing long-sleeved shirts and long pants, applying insect repellent containing DEET and regularly draining standing water to prevent mosquito breeding.

Most people bitten by a West Nile-infected mosquito show no symptoms. But if they do become sick, symptoms typically show from three days to two weeks later.

About one in five people infected with the virus will have a mild illness with fever, headache and body aches, sometimes with a skin rash and swollen lymph glands. Severe cases may result in encephalitis, meningitis or death.