Measles cases nearly double last year's high. See where cases are up

US measles cases reach 4,410 in 2026, nearly double last year's total

The CDC reported 4,410 confirmed measles cases in the US as of October 15, 2026, an 8.1% week-over-week increase of 330 cases. The total far exceeds 2025's count of 2,289 cases, with Pennsylvania emerging as a major outbreak hotspot prompting the CDC to deploy a disease detective to the state.