Tick 'Hot Spots' In Illinois: Study IDs Worst Places For 'Disease-Carrying Ticks'

If you've been outdoors at all this summer, you may already seen a tick crawling near or on you.

The Illinois Department of Public Health reminded Illinoisans that the "warmer weather means an increased potential for exposure to several illnesses that can be carried by animals or biting pests."

One of the main areas of concern for this time of year is ticks and tickborne illnesses.

"Ticks can spread a number of potentially serious illnesses, including Lyme disease, spotted fever group rickettsiosis, ehrlichiosis, and others," IDPH said.

The University of Illinois Urbana-Champaign released results of a study last fall that identified "hotspots of disease-carrying ticks in Illinois." The study analyzed three different tick species: the lone star tick, the black-legged tick or deer tick, and the dog tick.

For most of the Chicago area, the dog tick and the black-legged tick were reported. Lake County reported all three species.

However, all three are likely present in every Illinois county, said Rebecca Smith (IGOH co-leader/CGD), a pathobiology professor at the University of Illinois Urbana-Champaign who led the new research with graduate student Abrar Hussain.

The data included 1,414 ticks collected in 80 Illinois counties from 2018 to 2022, according to the study. Researchers shared that Hamilton, Pope and Macon counties (all in southern or central Illinois) had the highest tick-collection numbers.

In the Chicago area, Kane County had the highest number of deer ticks reported, and Cook, DuPage and Kendall counties were identified as "clusters" (higher-than-expected tick distributions) for the deer tick, according to the study.

According to IDPH data, Chicago-area counties reported the following for human Lyme disease cases in 2024:

• Lake County, 36 cases
• Cook County, 102 cases
• DuPage County, 30 cases
• Will County, 14 cases
• Kane County, 21 cases
• McHenry County, 30 cases

Some tips to avoid ticks include, per IDPH:

• Walk in the center of trails. Avoid wooded, bushy areas.
• Wear light-colored clothing so you can more easily see ticks. Tuck long pants into socks and boots.
• Apply an EPA-registered insect repellent containing 20 percent DEET, picaridin, IR3535, or oil of lemon eucalyptus according to label directions.
• Do a full-body tick check (underarms, ears, belly button, behind knees, between legs, waist, hair and scalp) every two to three hours if you've been outdoors.