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State guide · IllinoisLyme disease in Illinois
How common Lyme disease is in Illinois, which ticks spread it, when to be careful, and where to turn for care.
Case numbers come from CDC’s 2023 annual notifiable disease tables, the most recent year CDC has published. Rates use U.S. Census 2023 population estimates. Reported cases undercount real infections. How to read these numbers.
How common is Lyme disease in Illinois?
In 2023, Illinois reported 372 Lyme disease cases, about 3.0 per 100,000 residents, well below the national rate. Reported numbers here are lower than in the Northeast, but low reported numbers do not mean no risk: cases can be missed, and doctors may be less likely to suspect Lyme where it is less familiar.
Illinois compared with neighboring states (2023)
| State | Reported cases | Per 100,000 |
|---|---|---|
| Wisconsin | 6,283 | 106.3 |
| Iowa | 212 | 6.6 |
| Indiana | 257 | 3.7 |
| Illinois | 372 | 3.0 |
| Kentucky | 120 | 2.7 |
| Missouri | 16 | 0.3 |
Which ticks spread Lyme in Illinois?
The blacklegged tick, which spreads Lyme disease, is widely distributed across the eastern United States, according to CDC, and its range includes Illinois. The lone star tick is also common here. It does not spread Lyme, but CDC notes its bite can be followed by a similar-looking rash called STARI and is linked to alpha-gal syndrome, a red meat allergy.
When to be most careful
Ticks are most active from spring through early fall, and in warmer parts of the state they can be out much of the year. Check yourself, your children and your pets after time in wooded or brushy areas.
How to protect yourself
- Use an EPA-registered insect repellent (such as DEET, picaridin, IR3535, oil of lemon eucalyptus, PMD or 2-undecanone).
- Treat clothing and gear with permethrin.
- Check your body, children and pets for ticks after being outdoors.
- Shower soon after coming inside, and tumble dry clothes on high heat for 10 minutes to kill ticks.
Found an attached tick? Remove it right away. Here’s what to do after a tick bite, and the symptoms to watch for over the next few weeks.
Where to get care in Illinois
Start with your primary care provider, an urgent care clinic or a telehealth visit, especially if you have a rash or fever after a tick bite. Tell them about any tick bite and where you have traveled. For complicated or lingering symptoms, ask about a referral to an infectious disease specialist. We are building a care finder with clinics that treat tick-borne illness; until then, here’s how Lyme testing works.
Official resources
- Illinois Department of Public Health: Deer ticks infected with Lyme bacteria have been found in Illinois.
- CDC: Lyme disease
We are collecting real experiences about Lyme disease in Illinois from people who have lived it, shared with their permission. As stories come in, they will appear here, clearly marked as personal experience rather than medical advice.
Frequently asked questions
Is Lyme disease common in Illinois?
Illinois reported 372 cases in 2023, about 3.0 per 100,000 residents (low reported on our map). Reported cases undercount real infections, so take precautions in tick habitat either way.
What tick carries Lyme disease in Illinois?
The blacklegged tick, often called the deer tick. The lone star tick and American dog tick do not spread Lyme.
Can I get Lyme disease in Illinois if reported cases are low?
Low reported numbers do not mean zero risk. Some infections are never reported, and cases are counted where people live, not where they were bitten. If you have symptoms after a tick bite or travel, see a healthcare provider.