Pennsylvania Measles Outbreak: 1,222 Cases and Five Deaths as State Becomes Epicenter of Worst U.S. Measles Year Since 1990s

• by Shimanta Das
• October 17, 2026

Pennsylvania is grappling with a severe measles outbreak that has now infected 1,222 people across 42 counties, with 225 hospitalizations and five confirmed measles-associated deaths, according to the Department of Health (DOH). Since October 9, 2026, 86 new positive cases have been reported, underscoring the outbreak’s rapid spread. The Keystone State now accounts for more than a quarter of all measles cases in the United States, sitting at the epicenter of the nation’s worst measles year since the early 1990s. The DOH remains committed to transparent reporting and has added an epi-curve to its measles dashboard to provide near real-time context on how the outbreak is evolving.

Measles is notoriously contagious, and part of what makes it so difficult to contain is that the virus can remain infectious in the air and on surfaces for up to two hours after the infected person has left the area. This explains why outbreaks can spread rapidly in schools, healthcare facilities, and other congregate settings. While the majority of cases are among unvaccinated individuals, only four cases (less than 1%) have occurred in vaccinated people, highlighting the overwhelming effectiveness of the measles vaccine. The DOH emphasizes that getting fully vaccinated remains the best protection against measles. The nation eliminated domestic measles spread in 2000 by maintaining high vaccination rates, but those rates have fallen in recent years to below the 95% coverage needed to prevent outbreaks.

The outbreak is not isolated to Pennsylvania. Earlier in October, New York Governor Kathy Hochul declared an emergency due to rising case numbers, while Ohio, South Carolina, Texas, and Utah have also seen significant increases. The five deaths in Pennsylvania include a woman whose primary cause of death was a probable acute cardiac event due to possible complications of measles, according to a coroner’s office spokesperson. These fatalities serve as a stark reminder of the serious complications that can arise from measles, which can include pneumonia, encephalitis, and death, especially in young children and immunocompromised individuals.

As the outbreak continues, health officials are urging residents to ensure they are