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.

The surge in measles cases in Texas began in late January when two cases were reported in Gaines County, as reported by The Houston Chronicle. Since then, the number of cases in Gaines County reached 80,

The measles outbreak in Texas has grown to 124 known cases across nine counties, according to new data released Tuesday afternoon by the Texas Department of State Health Services.