AMERICA’S MEASLES outbreak is alarming for several reasons. What began as a handful of cases in Texas in January has now exceeded 800 across several states, with many more cases probably going unreported. It is the worst outbreak in 30 years and has already killed three people. Other, smaller outbreaks bring the total number of cases recorded in 2025 so far to over 1,000. But above all, public-health experts worry that the situation now is a sign of worse to come. Falling vaccination rates and cuts to public-health services could make such outbreaks more frequent and impossible to curb, eventually making measles endemic in the country again.