Already in 2025, the United States has reported more measles cases than in any full year since the early ‘90s, according to federal data. And that record-setting case count has been driven by a massive outbreak that began in Texas.

The U.S. is having its worst year for measles spread since 1991, with a total of 1,288 cases nationally and another six months to go. But in Gaines County, Texas, which was once the nation’s epicenter for measles activity,