Riverside officials announced Thursday that a dead bird collected in Riverside by the Cook County Department of Public Health has tested positive for West Nile virus.

The virus, which is spread by mosquitoes, can cause people to experience a range of symptoms from mild to severe. The symptoms include fever, headaches and body aches. More severe symptoms, according to the Cook County Department of Public Health, include high fever, stiff neck, confusion and muscle weakness.

“Residents need to remember that West Nile virus is real and to be vigilant in protecting against it, because it’s found every year in our communities,” said Dr. Terry Mason, the chief operating officer of the Cook County Department of Public Health in a press release. “Unless basic prevention steps are taken to limit the risk, breeding grounds can develop around home and put people at risk for the infection.”

The Culex mosquito, which breeds in small pools of stagnant water, carries West Nile virus. In order prevent the spread of Culex mosquitoes, the health department recommends removing any small pools of stagnant water, including bird baths, flower pots, old tires, pet food bowls and baby pools.

To protect yourself against mosquito bites, they recommend applying an insect repellent with DEET and repairing or replacing screens on doors and windows.

According to the U.S. Geological Survey, there have been no cases reported in 2014 of humans contracting West Nile in Illinois. However, there have been numerous positive tests done on mosquitoes in the state, including 29 in Cook County. Just seven birds had tested positive for West Nile in the state and none in Cook County prior to the Riverside test result, according to a USGS map.