Pennsylvania’s measles outbreak is the country’s largest in three decades, tell me about this news today

Pennsylvania health officials confirmed that the state has surpassed 1,000 measles cases this year, reaching 1,004 confirmed infections and marking the largest outbreak within a single U.S. state in over three decades.

• Scale and Geographic Spread: The outbreak, which began spreading in April, has expanded across 39 of the state’s 67 counties. It recently added more than 100 cases in a single week.

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• Vaccination Status: State health department data indicates that over 99% of those infected were unvaccinated, with only four cases confirmed among vaccinated individuals.

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• Hospitalizations and Fatalities: Approximately 198 patients have required hospitalizationa rate of nearly 20%. Five measles-associated deaths have been confirmed, including two infants with underlying conditions, an 18-year-old who developed encephalomyelitis, a 20-year-old undergoing chemotherapy for leukemia, and a 40-year-old with chronic respiratory disease. This represents the highest measles death toll in the nation in over 30 years.

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• Historical Context: While local clusters have emerged in recent years across various states, an outbreak exceeding 1,000 cases inside a single state has not been recorded since the nationwide resurgence of the late 1980s and early 1990s, when Philadelphia itself experienced a deadly outbreak of roughly 1,400 cases in 1990–1991.