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Pennsylvania’s measles outbreak has surpassed 1,000 cases, marking the largest since the disease was declared eliminated in the United States in 2000. Health officials reported 1,078 total cases for 2026 as of this afternoon, with the vast majority occurring since April when the current outbreak began. This tally includes 207 hospitalizations and five deaths among unvaccinated individuals, including two infants too young to be vaccinated. Experts widely expect the US to have lost its measles elimination status, a condition maintained by vaccination rates that prevent continuous transmission for twelve months.

The situation is part of a broader trend with slipping vaccination rates nationwide. The current outbreak in Pennsylvania exceeds the previous record holder, an April-ending outbreak in South Carolina with 997 cases. A large Texas outbreak spanning January through August 2025 resulted in 762 cases. While measles was historically a late winter and early spring virus, experts are anxious as outbreaks stretch into the fall, fearing acceleration under favorable conditions. The Centers for Disease Control and Prevention reports 3,887 nationwide cases, the highest since 1991 when there were 9,643.

In response to rising cases, New York Governor Kathy Hochul declared a State Disaster Emergency. There have been at least 108 cases in the state. The declaration expands the pool of healthcare workers who can provide vaccinations and order tests, including paramedics, pharmacists, and nurses. "No one should get seriously ill or die from a vaccine-preventable disease," Hochul stated. In November, experts at the Pan American Health Organization will review data on whether the US has lost its elimination status. The last larger outbreak occurred in New York between 1990 and 1991, infecting over 4,500 people.