By Marie Rosenthal, MS
Updated May 9 with latest CDC data
The total number of measles cases as of May is more than three times higher than previously reported all of last year.
As of May 1, 2025, a total of 1001 cases of measles have been confirmed by 31 jurisdictions in the United States; by Dec. 31, 2024, a total of 285 measles cases were reported by 33 jurisdictions. Fourteen separate outbreaks (defined as three or more related cases) have been reported to date in 2025, and 93% of confirmed