A Texas measles outbreak has doubled in the last week to 124 cases, state health officials said Tuesday, a day after they warned a person infected with the highly contagious disease had traveled from the outbreak zone.

A child hospitalized with measles in West Texas has died. It's the first death in an outbreak that began last month.

The first person known to have died from measles in the U.S. in a decade was announced by health officials on Wednesday and described as a "school-aged child" who perished in a children's hospital in West Texas,