As of March 7, 2025, the Centers for Disease Control and Prevention (CDC) stated that a total of 222 measles (rubeola) cases had been reported in 12 different U.S. jurisdictions: Alaska, California, Florida, Georgia, Kentucky, New Jersey, New Mexico, New York City, Pennsylvania, Rhode Island, Texas, and Washington. Among those cases, 94% were either unvaccinated or had an unknown vaccination status. Seventeen percent were hospitalized, with the majority of those cases among children 19 years of age or younger. Unfortunately, measles has already claimed the life of an unvaccinated child in Texas, which is reporting the largest outbreak, at 159 cases. The cause of a second death, of an unvaccinated deceased adult in New Mexico who was found to have measles, is still under investigation.

Measles is an airborne, highly infectious, and potentially severe illness. The vaccine [measles-mumps-rubella (MMR)] vaccine is more than 97% effective in preventing disease. In the United States, MMR coverage among kindergartners is now below the 95% coverage target, with rates much lower in some communities, and is continuing to decrease. In addition, global measles activity is increasing, leading to more opportunities for an unvaccinated person to become infected when traveling outside the U.S. or for an infected person visiting or living in the U.S. to transmit to a susceptible unvaccinated person. Groups of unvaccinated individuals provide opportunities for ongoing transmission and the resultant illness. These outcomes are preventable.