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 measles outbreak in northwest Texas grew to 124 cases in nine counties on Tuesday, and health officials warned that residents in other parts of the state may have been exposed to the highly contagious respiratory illness.

A measles outbreak in Texas continues to grow. State health officials say the outbreak is the largest in the state in nearly 30 years.