Dossier
measles, mumps and rubella vaccine
Coverage of measles, mumps and rubella vaccine in the Nexus archive.
- There are already more U.S. measles cases this year than in all of 2025
The U.S. has recorded more measles cases in 2026 than in all of 2025, with major outbreaks in South Carolina, Utah, and Arizona. Vaccination rates have dropped below the 95% threshold needed to prevent outbreaks, and experts warn official case counts are likely underestimates due to unreported cases and the virus's high contagiousness.