At least 124 cases of measles have been reported in Texas since late January — marking the largest outbreak in the state in close to 30 years. The dozens of reported cases have mostly affected children,

Texas reported 90 cases this week, while New Mexico reported nine. A majority of the cases have been in a Texas county where vaccination rates have lagged behind the rest of the state.

The measles outbreak in Texas has reached nearly 150 cases, according to a Friday morning update from the state health department. The agency said 146 cases have been identified since late January. Twenty of those patients have been hospitalized, and one school-age, unvaccinated child has died.