U.S. Could Lose Measles Elimination Status as PAHO Review Weighs 5,182 Cases This Year
A Pan American Health Organization commission is reviewing whether the United States still meets the definition of measles elimination after the CDC recorded 5,182 cases in 2026, the most since 1991. A decision is expected by November 17.
A panel of international health experts began reviewing this week whether the United States still qualifies as free of endemic measles, after the country recorded its highest annual case total in 35 years. The Pan American Health Organization’s Regional Verification Commission opened its review on Nov. 10 and is scheduled to meet through Nov. 13, with a public decision expected by Nov. 17, according to the Washington Post.
The Centers for Disease Control and Prevention has recorded 5,182 confirmed measles cases in 2026 as of Nov. 5, more than double the 2,289 reported in all of 2025 and the most since 1991. The agency has identified 43 new outbreaks this year, and 96 percent of infections are linked to outbreaks. About 11 percent of confirmed cases required hospital care: 562 people, including 154 children under 5.
What losing the status would mean
The United States was declared free of endemic measles in 2000, meaning domestic transmission had been interrupted for at least 12 months, though imported cases could still occur. The review will determine whether the same measles genotype and lineage has circulated without interruption for 12 months or more, the threshold for re-established endemic transmission.
Noel Brewer, chairman of the U.S. committee reviewing national measles surveillance, said publicly available data indicated two transmission chains had lasted longer than a year. The resurgence began with a large outbreak in western Texas in January 2025 and spread to Utah, Arizona and other states.
Vaccination rates have fallen
Childhood vaccination coverage has slipped. Measles, mumps and rubella vaccination among kindergarten pupils fell from 95.2 percent in the 2019-20 school year to 92.4 percent in 2025-26, according to CDC figures, and roughly 280,000 kindergarten children lacked documentation of completing the recommended series. Exemptions rose to 4.2 percent from 3.6 percent the year before. An NBC News investigation found about three-quarters of counties with recent kindergarten data were below the 95 percent coverage level needed for community protection.
Among confirmed patients in 2026, 96 percent were unvaccinated or had no recorded vaccination status. Two doses of the MMR vaccine are about 97 percent effective against measles, according to CDC data. State health departments have recorded 11 measles-related deaths since early 2025, Reuters reported, compared with seven deaths in the CDC’s national figures for 2025 and 2026.
Health Secretary Robert F. Kennedy Jr. has repeatedly questioned the combined MMR vaccine, while medical experts have raised concerns about the effects of anti-vaccine messaging on public confidence. CDC Director Erica Schwartz said the agency would keep supporting state outbreak responses and promoting vaccination even if the country loses the designation. U.S. officials are presenting the commission with laboratory findings and data on how infections spread between communities.
Measles is a highly contagious airborne infection that can cause pneumonia and encephalitis, and children under 5 face the highest risk of severe complications.
Reporting based on coverage by Medical Daily and the Pan American Health Organization.
