CHICAGO (CBS) — The Illinois Department of Public Health confirmed the first mosquitoes to test positive for West Nile virus in Illinois so far this year.

According to the IDPH, staff at the North Shore Mosquito Abatement District collected mosquitoes that tested positive on May 25, 2018 in Glenview and Morton Grove.

While the mosquitoes tested positive for the virus, no human cases of West Nile have been reported in 2018.

The Illinois Department of Public Health recommends wearing insect repellent and getting rid of standing water in residential areas.

People who observe a sick or dying cow, blue jay, robin, or other perching bird should contact their local health department, where officials will determine if the animal will be picked up for testing.

According to a press release from the public health department, “West Nile virus is transmitted through the bite of a Culex pipiens mosquito, commonly called a house mosquito, that has picked up the virus by feeding on an infected bird.  Common symptoms include fever, nausea, headache and muscle aches.  Symptoms may last from a few days to a few weeks.  However, four out of five people infected with West Nile virus will not show any symptoms.  In rare cases, severe illness including meningitis or encephalitis, or even death, can occur.  People older than 60 and individuals with weakened immune systems are at higher risk for severe illness from West Nile virus.”

The North Shore Mosquito Abatement District says they will be conducting targeted adult mosquito control spray operations in Lincolnwood, Morton Grove, Niles, and Skokie on Thursday, May 31 between 8 p.m. and 2 a.m., weather permitting.

63 counties in Illinois reported a positive batch of mosquitoes that tested positive for West Nile virus in 2017.

Last year, the IDPH reported 90 human cases, including eight deaths.