As of May 5, 2025, the United States is experiencing its most severe measles outbreak in over two decades, with Texas and New Mexico at the epicenter.​ Current Case Counts and Impact Origin and Spread The outbreak began in January 2025 within a close-knit Mennonite community in Gaines County,

Texas’ measles outbreak has grown to 702 cases across 29 counties, according to a Tuesday update from the state public health department. The Texas Department of State Health Services estimates that less than 1% of those cases — or fewer than 10 of the reported cases — are “actively infectious.