science

Thirty states have had measles cases this year; 47 have seen cases since the start of 2025. Health officials across the U.S. have confirmed 1,300 infections already this year as of March 6, putting the country on track to surpass 2025’s numbers, which were the highest in 35 years.

We study outbreak preparedness and response at Brown University’s Pandemic Center, and we view the return of measles in the U.S. as a grim signal of what’s to come.

Low levels of vaccination across the country mean measles outbreaks will continue to occur, needlessly hospitalizing and killing the unvaccinated. But beyond these harms, the disease’s resurgence serves as a serious warning about the country’s capacity to manage infectious disease threats of all kinds.