Distribution of measles cases in the U.S. in 2024 and 2025, by vaccination status

In 2024, there were a total of 285 cases of measles in the United States. Around 89 percent of these cases were among those who were unvaccinated or whose vaccination status was unknown. From January 1 to April 3, 2025, there were 607 cases of measles, with those who were unvaccinated or with an unknown vaccination status accounting for 97 percent of these cases. Measles is a highly contagious disease that can be especially dangerous for young children. Vaccines against measles resulted in a significant decrease in cases in the United States over the last few decades; however, increasing vaccine hesitancy and skepticism has been blamed for recent outbreaks.