Major US airport on red alert as passenger is diagnosed with world’s most infectious disease

Health authorities are urging heightened vigilance after confirming a potential measles exposure at Chicago’s O’Hare International Airport, one of the busiest transportation hubs in the world. Officials say an adult who was later diagnosed with measles spent significant time in Terminal 1 on April 22 and April 23, between 10 a.m. and 8 p.m. each day, raising concerns that hundreds of travelers and airport workers may have been exposed.

The individual, who had received one prior dose of the measles, mumps, and rubella (MMR) vaccine, was not aware they were infected at the time of travel. According to health officials, the person developed a rash on April 25, a common symptom of measles, and subsequent testing confirmed the infection. Since receiving the diagnosis, the individual has been isolating at home to prevent further spread.

Measles is considered one of the most contagious diseases in the world, capable of spreading through airborne particles that can linger in enclosed spaces long after an infected person has left. This makes airports particularly vulnerable locations for transmission, given the high volume of travelers and the close proximity in terminals, security lines, and boarding areas.

Adding to concerns, officials confirmed a second measles case several days later involving another adult who lives in the same Illinois county. While this individual’s vaccination status remains unknown, they sought medical care at a local hospital on April 28. Hospital staff acted quickly to isolate the patient, limiting the risk of exposure to others within the facility.

Public health officials are advising anyone who was at O’Hare’s Terminal 1 during the specified dates and times to remain alert for symptoms such as fever, cough, runny nose, red eyes, and rash. Those who believe they may have been exposed are encouraged to contact their healthcare provider before visiting a clinic or hospital. This incident is the latest in a series of measles-related alerts affecting major U.S. airports and nearby communities, underscoring renewed concerns about the disease’s spread.