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. Other states with outbreaks — defined as three or more cases — include New Mexico, Kansas, Ohio and Oklahoma. Since February, two unvaccinated people have died from measles-related causes.

The Texas health department said on Friday that the number of measles cases in the state rose 20% since its last report three days ago, as experts warn they expect the outbreak to further spread in coming weeks.

Measles outbreaks are surging in 5 U.S. states, with over 400 cases in Texas and two deaths. Here’s what to know.