When Texas officials first discovered measles cases this year, they were among the Mennonite population. Now, officials say cases are spreading to other communities.

At least five states have active measles outbreaks as of Friday, and Texas' is the largest with 400 cases. Already, the U.S. has more measles cases this year than in all of 2024, the U.S. Centers for Disease Control and Prevention has said.

Texas has reached 400 cases of measles in an outbreak that started two months ago. Texas, New Mexico, Ohio, Kansas and Oklahoma all have active measles outbreaks.