Scientists warn that falling vaccination rates leave vulnerable groups such as young children more exposed to disease.

The United States has recorded more measles cases this year than in any year since 1991, with more than five months still left on the calendar.

Measles vaccines helped the U.S. eliminate measles 26 years ago

2026 has become the worst year for measles since 1991

The U.S. has surpassed 2025’s record for measles cases, with five months left in 2026