IDPH reports first human case of West Nile virus in Illinois in 2024

The Illinois Department of Health announced the first human case of West Nile virus in Illinois in 2024. While commercial and clinical symptoms indicate a case of West Nile virus, IDPH routinely sends the first positive case to the Centers for Disease Control and Prevention for confirmatory testing, which is pending. The affected individual is in their 60s and lives in suburban Cook County. The onset of West Nile virus symptoms was in mid-June.

IDPH is tracking positive batches of birds and mosquitos on its West Nile virus dashboard and has reported 33 Illinois cases with positive results this year, an early warning of the presence of West Nile virus in an area. There were 119 human cases of West Nile virus reported in Illinois in 2023, up from 34 cases in 2022. Six human deaths were attributed to West Nile virus in 2023, compared to seven in 2022. The first human case in 2023 occurred in late June.

IDPH encourages the public to Fight the Bite and take steps to prevent West Nile virus by practicing the three Rs – reduce, repel and report:

• Reduce - Make sure doors and windows have tight-fitting screens. Repair or replace screens that have tears or other openings. Try to keep doors and windows shut. Eliminate, or refresh each week, all sources of standing water where mosquitoes can breed, including water in bird baths, ponds, flowerpots, wading pools, old tires and any other containers.

• Repel - When outdoors, wear shoes and socks, long pants and a light-colored, long-sleeved shirt. Apply an EPA-registered insect repellent that contains DEET, picaridin, oil of lemon eucalyptus or IR 3535, according to label instructions. The CDC does not recommend using products containing oil of lemon eucalyptus or para-menthane-diol on children younger than 3 years old. Consult a physician before using repellents on children younger than 3.

• Report – Report locations where you see water sitting stagnant for more than a week such as roadside ditches, flooded yards and similar locations that may produce mosquitoes. The local health department or city government may be able to add larvicide to the water, which will kill any mosquito larvae.