In its latest update, the Texas Department of State Health Services (DSHS) reported 198 cases of measles across West Texas. The number of cases in neighboring New Mexico also tripled in a day to 30, local health officials said.

A measles outbreak in Texas has grown to 159 cases, and the US Centers for Disease Control and Prevention says it is now on the ground in that state to respond. The agency posted on X that it’s partnering with the Texas Department of State Health Services.

A child’s death this past week in Texas is the first U.S. death from measles, a highly contagious but preventable respiratory disease since 2015, according to the U.S. Centers for Disease