Cook County warns of potential measles exposures at O’Hare, Niles and Mount Prospect

The Cook County Department of Public Health is warning of possible measles exposures in Chicago’s northwest suburbs.

The possible exposure was last week. The virus can remain in the air for up to two hours after an infectious person has left the area, though transmission requires just 15 minutes of exposure, the health agency said.

The possible exposure locations are:

• O’Hare Airport’s Terminal 5, March 26 from 10:45 a.m. to 2:30 p.m.
• Fresh Farms, 8203 W. Golf Road, Niles, March 26 from 7:30 p.m. to 9:00 p.m.
• Marshalls, 8249 W. Golf Road, Niles, March 26 from 8 p.m. to 9:30 p.m.

The infected person also visited Endeavor Health Immediate Care Center in Mount Prospect Friday, and county officials are working to reach people who may have been in exposed.

Those most at risk are babies, young children, pregnant women and people with compromised immune systems. Vaccinated individuals are typically not at risk since two doses provides 97% protection. The health agency advises those who may have been exposed to consult a health care provider.

People experiencing symptoms — rash, high fever, cough, runny nose, and red, watery eyes — should call a health care provider before going to a clinic to help control the spread of the virus, the agency said. Measles symptoms appear up to 21 days after exposure, as well as four days before and four days after the onset of the rash, which starts on the face and spreads to the body.

Illinois saw 14 measles cases in 2025 during its peak — when nearly 1,300 cases cropped up nationwide, the worst outbreak in more than 30 years. It was a sharp drop from the three-month measles outbreak in Chicago, where 64 cases were confirmed in 2024.

Those not vaccinated should talk to their provider about getting vaccinated, as doing so may prevent measles if administered within 72 hours after exposure, the health agency said. An appointment with a Cook County Health clinic can be made by calling 312-864-1111.