There are already more U.S. measles cases this year than in all of 2025
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- CDC logged 2,318 U.S. measles cases as of Thursday per its Friday update, surpassing 2025's full-year total of 2,289 and making 2026 the worst year for measles in the country since 1991, with five months still to come.
- Major outbreaks in South Carolina, Utah, and Arizona are driving the surge; South Carolina alone has 997 cases — the nation's largest outbreak in 35 years — though state officials acknowledge the count is an undercount of unknown magnitude.
- International health officials will meet in November to determine if the U.S. and Mexico have lost their measles-free status; the U.S. eliminated local measles spread in 2000 by maintaining vaccination rates above 95%, but national MMR coverage among kindergartners has fallen to 92.5% in 2024-25 from 95.2% in 2019-20.
- In Utah, where more than 700 people have been sickened in over a year, mathematical modeling and genetic analyses indicate the Utah-Arizona border outbreak could be three to four times larger than what's currently known, state epidemiologist Dr. Leisha Nolen said.
- Texas researchers estimate the state's 2025 outbreak may have been nearly twice the 762 known cases, and 182 probable cases went unconfirmed in March 2025 among minors in Gaines County — the epicenter — due to a lack of information, according to chief state epidemiologist Dr. Varun Shetty.
- Dr. Mark Roberts, retired director of the Public Health Dynamics Lab at the University of Pittsburgh, warned that unvaccinated people endanger 'innocent bystanders' — infants, immunocompromised individuals, and others who cannot be vaccinated — comparing skipping vaccination to removing brakes from a car because 'it's other people that you can hit.'
Why it matters: The U.S. is on track to lose its measles-free status at a November international review, a designation it has held since 2000. With kindergarten MMR coverage at 92.5% — below the 95% threshold needed to prevent outbreaks — measles is spreading fastest among infants, immunocompromised people, and others who can't be vaccinated themselves, and the true case count is likely far higher than official figures show.
