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The CDC has now confirmed two measles-related deaths in the U.S. in 2026, up from one earlier, as the country battles its worst measles resurgence in 35 years. With 3,659 confirmed cases as of September 24, the outbreak — centered heavily in Pennsylvania — has sparked political disputes over how deaths are classified and growing alarm over falling vaccination rates.
The U.S. measles crisis is deepening. The CDC has officially confirmed two measles-related deaths in 2026, up from one previously acknowledged, as cases continue to climb — reaching 3,659 confirmed infections as of September 24. Pennsylvania has been the hardest-hit state, reporting four measles-associated deaths and over 730 cases across 38 counties, with Lancaster County at the epicenter.
The outbreak has become politically charged. Pennsylvania Governor Josh Shapiro and HHS Secretary Robert F. Kennedy Jr. have publicly clashed over how deaths should be classified, with Kennedy asserting only one death was directly caused by measles. The CDC shifted to using mortality data from its National Center for Health Statistics — rather than state health departments — for its national death count, a move that drew scrutiny and calls for a standardized definition of measles-related deaths.
By the Numbers:
Why it matters: The U.S. measles elimination status — achieved 26 years ago — is now under serious threat and up for review in November. Declining vaccination rates, political friction over vaccine policy, and a proposed executive order to split the MMR vaccine into three separate shots are compounding the public health risk, leaving more communities vulnerable to a disease that is entirely preventable.