It takes a lot to knock football out of the headlines in Pittsburgh. But reports of measles cases, exposure alerts and calls for residents to double-check their vaccination status have dominated local news since August 2026.

My office at Allegheny College, where I am an epidemiologist, is within a few steps of a classroom dedicated to Dr. Thomas Francis. Francis coordinated the entire polio vaccine field trial, which included 1.8 million children, and deemed the polio vaccine “safe, effective, potent.”

As of Sept. 14, 2026, the Pennsylvania Department of Health has confirmed 693 measles cases across 38 of the state’s 67 counties this year, including 133 hospitalizations and four deaths among unvaccinated residents. That compares with 16 cases statewide in all of 2025.

Allegheny County reported its first case tied to the current outbreak in August, when the county health department warned of a potential exposure at UPMC Children’s Hospital’s emergency department. Two confirmed cases were diagnosed on Aug. 27, 2026, but the patients left the county afterward.

Pittsburgh is where Dr. Jonas Salk developed the first polio vaccine on the campus of the University of Pittsburgh. Children throughout the Pittsburgh area, including my father, lined up to participate in the Salk vaccine trials in 1954.

That history offers a useful lens for understanding today’s measles outbreak: what’s driving it, how it spreads, and what residents in the........

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