DuPage County confirms first measles case of 2026

CHICAGO – A vaccinated DuPage County resident has been diagnosed with measles after returning from international travel, health officials said.

DuPage County measles case

The DuPage County Health Department said the case is a rare breakthrough infection. Measles after vaccination is uncommon but can occur after intense or prolonged exposure to someone with the virus.

Vaccinated people who develop measles typically have milder illness, are less likely to experience complications and may be less likely to spread the virus.

“Our community’s safety is our priority. Our team is actively working on following up with individuals who may have been potentially exposed,” said Adam Forker, executive director of the DuPage County Health Department. “Vaccination continues to provide strong protection, even in a rare breakthrough case.”

The health department is working with health care and public health partners to contact anyone who may have been exposed.

Possible exposure

Anyone who was at O’Hare Airport’s Terminal 5 on Thursday, Oct. 15, between 4:20 p.m. and 7 p.m. should report the potential exposure.

What you can do:

DuPage County residents can call the health department at 630-682-7400. People who live elsewhere should contact their local health department.

People should monitor for measles symptoms for 21 days after exposure, including fever, rash, cough, runny nose and red, watery eyes.

Anyone who develops symptoms should stay home, call a doctor and explain the possible exposure before visiting a health care facility. The health department also asks people with symptoms to call them.

Most DuPage County residents are protected through vaccination, and officials said the risk to the public is low.