CHICAGO (WCIA) — The Illinois Department of Public Health said on Thursday that it has confirmed the first mosquitoes in Illinois to test positive for West Nile Virus in 2022.

IDPH said the mosquitoes were found on Tuesday in the DuPage County community of Roselle. So far in 2022, no human cases of West Nile Virus have been reported in humans.

“This is the time of year when West Nile virus make its annual appearance,” said IDPH Acting Director Amaal Tokars. “We remind everyone — and especially older people and those with weakened immune systems — to take precautions to protect themselves from mosquitoes and the viruses they carry by wearing insect repellent and eliminating standing water around their home where mosquitos breed.”

West Nile Virus is transmitted though bites from mosquitoes that fed on an infected bird. Common symptoms include fever, nausea, headache and muscle aches and they typically last from a few days to a few weeks. However, four out of five infected people will not show any symptoms.

In rare cases. severe illness including meningitis, encephalitis or even death can occur. People over the age of 60 and people with weakened immune systems are at a higher risk for severe illness.

IDPH encourages the following precautions to prevent mosquito bites:

  • Reduce: Make sure doors and windows have tight-fitting screens without tears or openings and keep them shut. Also eliminate or refresh all sources of standing water weekly (this includes bird baths, ponds, flower pots, wading pools, old tires and other containers)
  • Repel: When outdoors, wear socks, shoes, long pants and long-sleeved shirts. Also apply insect repellent.
  • Report: Report locations where water sits stagnant for more than a week, including roadside ditches, flooded yards and similar locations. The local health department may be able to add larvicide to the water to kill mosquito larvae.

Last year, the first mosquitoes with West Nile Virus were found on June 9 in Skokie and 48 counties reported either an infected batch of mosquitoes or a case in a horse or human. 64 human cases were reported (although human cases are often underreported) and five people died.