MMR vaccine

The United States is experiencing its largest measles outbreak since the disease was declared eliminated in 2000, with at least 800 confirmed cases nationwide and likely more unreported.

A severe measles outbreak has spread to 21 states with over 600 confirmed cases in 2025, primarily affecting unvaccinated individuals, with experts suspecting significant underreporting of actual case numbers.

A significant measles outbreak originating in Gaines County, Texas has expanded to New Mexico, Oklahoma, Kansas, and Ohio, with 321 total cases reported across the affected regions.

The National Institutes of Health has canceled over 300 vaccine-related research projects, including studies focused on understanding and addressing vaccine hesitancy across various communities.