State health departments have reported eight measles deaths this year: six in Pennsylvania, one in New York and one in Wisconsin. The CDC has confirmed four, a figure it says is subject to change, and its count draws on National Center for Health Statistics mortality data. The most recent deaths include an unvaccinated resident of Jefferson County, Pennsylvania, and an unvaccinated infant in Lewis County, New York, the state's first measles death in more than 30 years. In southwestern Wisconsin, an infant died of measles, the state's first such death since 1990.

About 96% of cases are in people who were unvaccinated or whose vaccination status is unknown. Another 2% had one dose of the MMR vaccine and 2% had two. A total of 562 people, about 11% of cases, have been hospitalized. Adults 20 and older account for roughly 2,100 cases, about the same as the 2,100 among people aged 5 to 19, and 908 cases are in children under 5. Eighteen cases involve international visitors.

Cases have turned up in all but four states and Washington, D.C. Arkansas, Hawaii, Mississippi and Nevada have reported none. Pennsylvania is the hardest hit, with 1,487 cases and 287 hospitalizations, up from 106 cases the previous year. Its outbreak spans more than 40 counties, and the state declared an emergency on October 13. South Carolina has 670 cases and Utah 536. The CDC counts 43 outbreaks that began in 2026, responsible for more than 3,600 cases, while outbreaks that began in 2025 account for over 1,300 more.

The Pan American Health Organization is expected to decide next week whether the US keeps the measles elimination status it has held since 2000. The wider Americas region lost its status in November 2025 after sustained transmission in Canada.

The CDC recommends a first MMR dose at 12 to 15 months and a second at 4 to 6 years. One dose is about 93% effective against measles and two doses about 97%. Vaccination coverage among kindergartners was 92.4% in the 2025-26 school year, down from 95.2% in 2019-20.