O'Hare International Airport travelers warned of measles exposure

Health officials have issued a warning following a confirmed measles case in a vaccinated DuPage County resident who recently returned from international travel. The individual was at O'Hare International Airport's Terminal 5 on Thursday, Oct. 15, between 4:20 p.m. and 7:00 p.m., potentially exposing other travelers.

The DuPage County Health Department described the case as a rare breakthrough infection. While the MMR vaccine is highly effective, officials noted that breakthrough cases can occur during intense or prolonged exposure. The department is actively working to follow up with individuals who may have been exposed.

As of October 2026, the Illinois Department of Public Health has confirmed 24 measles cases in the state. Anyone who was in Terminal 5 during the specified window is encouraged to check their travel records and contact health officials.