As measles cases in West Texas are still on the rise two months after the outbreak began, local public health officials say they expect the virus to keep spreading for at least several more months and that the official case number is likely an undercount.

A measles outbreak that began in Texas at the start of the year has infected nearly 330 people as of Tuesday, while cases of the highly contagious illness have been spotted Washington, D.C., and 17 states, exceeding the total number of measles cases reported in 2024.

Measles cases in Texas and New Mexico rose to 370 on Friday, the health departments of the states said, an increase of 19 infections since their previous reports four days ago, as the United States deals with one of the largest measles outbreaks in the past decade.