A child in West Texas has died of measles, state health officials said on Wednesday, the first reported U.S. death from the highly contagious disease in a decade, as a Texas outbreak has grown from a handful of cases to more than 130 across two states.

The unvaccinated school-age child is the first confirmed fatality in Texas’s worst measles outbreak in three decades.

A person who was hospitalized with measles has died in West Texas, marking the first death in an outbreak that began late last month.