# US measles exposure incidents at major airports

> Live situation record from CLSTR: https://clstr.news/situations/us-measles-exposure-incidents-at-major-airports
> Updated: 2026-10-22T01:04:23.000Z. Sources: 2. Developments: 2.

Public health officials have issued alerts regarding measles exposure at two major US airports. In late September, the Philadelphia Department of Public Health reported an exposure at Philadelphia International Airport affecting terminals B and F, as well as connecting areas C, D, and E. This followed a previous case at the Children’s Hospital of Philadelphia.

In October, health officials warned of a measles exposure at Chicago’s O’Hare International Airport in Terminal 5. The incident involved a vaccinated DuPage County resident who recently returned from international travel. The DuPage County Health Department characterized the case as a “rare breakthrough infection,” noting that such instances can occur during intense or prolonged exposure. As of October 2026, the Illinois Department of Public Health has confirmed 24 measles cases within the state.

## Timeline

### 2026-10-22: O'Hare International Airport travelers warned of measles exposure

A vaccinated DuPage County resident has tested positive for measles after international travel, prompting exposure warnings for travelers in O'Hare Airport's Terminal 5 on Oct. 15.

2 sources. https://clstr.news/cluster/ohare-international-airport-travelers-warned-of-measles-exposure

### 2026-09-25: Philadelphia airport issues measles exposure alert

Health officials issued an emergency alert after a measles exposure at Philadelphia International Airport between September 13 and 14, affecting multiple terminals.

4 sources. https://clstr.news/cluster/philadelphia-airport-issues-measles-exposure-alert

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Cite as: US measles exposure incidents at major airports. CLSTR, https://clstr.news/situations/us-measles-exposure-incidents-at-major-airports