The United States has logged more measles cases in 2026 than in any year since 1991, and the count keeps climbing as schools reopen.
The Centers for Disease Control and Prevention reported 3,134 confirmed cases as of September 3 across 47 jurisdictions, including New York City and the District of Columbia. Officials have identified 38 new outbreaks this year, and 95% of confirmed infections are linked to those clusters. In 2025 the country recorded 2,289 cases, itself the worst total in decades.
Outbreaks concentrate in under-vaccinated communities
Utah has been fighting an outbreak for 12 months, with 711 cases in that period and 514 of them in 2026. State data shows about 8% of patients were hospitalised, and 90% of those admitted were unvaccinated. More than 60% of hospitalised patients needed supplemental oxygen, and 29% developed measles pneumonia. Three of the five vaccinated patients who were admitted had severe immunocompromising conditions.
South Carolina's outbreak, which ran from October 2025 to April, produced 997 confirmed cases and at least 21 hospitalisations. Pennsylvania officials said this year that measles caused the deaths of two infants in Lancaster County, the first US measles deaths of 2026.
Elimination status under review
Measles needs roughly 95% vaccination coverage to stop sustained transmission. The Pan American Health Organization has warned that two years of continuous spread puts the country's elimination status, certified in 2000, in jeopardy. The CDC says about 20% of unvaccinated people who catch measles are hospitalised, and 1 in 20 develops pneumonia.
With classes back in session, paediatricians have published their own autumn vaccine guidance, filling what they describe as a gap left by federal agencies. 'We urgently need to address the reasons for under-vaccination in some of our communities, particularly the disinformation that leads to mistrust of measles vaccines,' said William Moss of the Johns Hopkins Bloomberg School of Public Health.