2025 Southwest United States measles outbreak

In January 2025, cases of measles began to appear in Texas and neighboring states in the United States. The outbreak became one of the largest in the country since 2000, when the United States declared the disease eliminated in the country. The outbreak was declared over on August 18, 2025.

Gaines County became the epicenter of the outbreak. By mid-February, the disease had spread to New Mexico and other communities in West Texas including Dallam, Dawson, Ector, Lynn, Terry, and Yoakum. In March, cases linked to the outbreak were announced in Oklahoma, the Mexican state of Chihuahua, and Kansas. Cases were concentrated in the Texas Mennonite community, and officials believed the disease was first imported from an outbreak in a Mennonite community in Ontario, Canada.

The outbreak was confirmed to have infected hundreds of individuals and suspected to have infected many more. More than 99 individuals were hospitalized, and three died: two children in Lubbock (a six-year-old and an eight-year-old) and an adult in Lea County, New Mexico. All three fatalities were unvaccinated individuals.

Measles is highly contagious and preventable by the MMR vaccine. Though the United States declared measles eliminated in 2000, waning vaccination rates had led to its resurgence in the country. By the end of 2025, the CDC confirmed 2,255 measles cases across 44 states and nearly 50 separate outbreaks.