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 measles outbreak that began in West Texas has now grown to well over 100 cases, with confirmed cases across Texas and New Mexico and possible exposures as far away as San Antonio and San Marcos.

A growing number of Central Texas health departments are warning residents of possible exposure to measles, the latest sign that the outbreak in West Texas is spreading across the state. Why it matters: Measles is a highly contagious and potentially life-threatening disease that has surged in areas with high vaccination exemption rates.