The largest recorded US measles outbreak in three decades has reached 41 Pennsylvania counties, with five deaths and nearly 200 hospitalisations reported as officials urge vaccination.
Pennsylvania’s measles outbreak has now surpassed 1,000 cases and spread into 41 counties, making it the largest recorded U.S. outbreak in three decades, according to state officials. The surge has come alongside five deaths linked to infection and nearly 200 hospitalisations, deepening pressure on public health leaders as respiratory virus season begins.
At a news conference in Pittsburgh on Monday, state Health Secretary Debra Bogen said the response remained extensive, with local and state agencies working alongside health partners across Pennsylvania. Bogen also noted that the first case tied to Allegheny County residents had been confirmed, although the exposure occurred in August at Children’s Hospital of Pittsburgh when infected visitors from outside the area came to the emergency room.
One of the clearest signs of the outbreak’s impact has been a sharp rise in vaccination. Pennsylvania providers normally give about 25,000 measles, mumps and rubella shots in a month, but that figure climbed to 49,000 in August and 53,000 in September, according to state data cited by officials. The Centres for Disease Control and Prevention says one dose of the MMR vaccine is 93% effective against measles, while two doses raise protection to 97%; the agency and other medical authorities continue to stress that the vaccine remains the best defence against infection and community spread.
Bogen used a stop at a pharmacy in Pittsburgh’s Allentown neighbourhood to press that message, saying the vaccine has protected children for decades and helped keep measles rare for much of that time. Even so, the outbreak continues to widen, with more than half of Pennsylvania’s 67 counties now reporting cases and nearly 30 new infections recorded over the weekend.
The outbreak has also exposed tensions between Pennsylvania and the Trump administration over how the crisis is being presented nationally. Bogen has said the state is still coordinating with federal health agencies, including the CDC, but she has also criticised the federal response after the CDC website listed only two of the five measles-associated deaths reported in Pennsylvania. In a letter to the agency last month, she said federal help would be reconsidered unless the deaths were publicly acknowledged accurately.
Despite that dispute, Bogen said Pennsylvania would still welcome support if it is offered, though she suggested the practical impact would be limited because the department already has hundreds of staff members involved in the response. She also warned that some schools may remain vulnerable, noting that many children in Allegheny County attend classrooms where immunisation rates fall below the recommended threshold, leaving pockets of the state at continued risk.
Disclaimer: This content is for informational purposes only and is not intended to be a substitute for professional medical judgment, advice, diagnosis, or treatment.
