At least 124 cases of measles have been identified in Texas since late January, mostly among children and teenagers who are either unvaccinated or whose vaccination status is unknown, officials say.

A measles outbreak in West Texas has topped 120 cases and resulted in the first U.S. death from the illness in a decade.

LUBBOCK, Texas (AP) — A person who was hospitalized has died from measles in West Texas, the first death in an outbreak that began late last month. Texas Tech University Health Sciences Center spokesperson Melissa Whitfield confirmed the death Wednesday. It wasn’t clear the age of the patient, who died overnight.