US measles cases 2026 reach 35-year high, CDC says

US measles cases in 2026 have climbed to 2,318 in the first seven months of the year, the Centers for Disease Control and Prevention reported Friday. The count has already passed the 2,289 cases logged last year and marks the nation’s highest measles total in 35 years.

The CDC said 93% of infected people are unvaccinated. The increase comes as childhood vaccination rates have declined over decades, and public health specialists say measles tends to show up first when community protection weakens because it spreads so easily.

Dr. Richard Besser, a pediatrician and president of the Robert Wood Johnson Foundation, said the United States has joined countries where vaccination is not reaching levels needed to protect children against highly contagious diseases. He called measles a warning sign for vulnerability to other vaccine-preventable illnesses, including whooping cough, meningitis and chickenpox.

Why are US measles cases rising in 2026?

Health officials and pediatricians cited falling vaccination rates in some communities as a major reason outbreaks are spreading. CDC data from 2025 showed 92.5% of children received measles vaccines, while about 95% of a population needs vaccination against measles to reach herd immunity.

Dr. Adam Ratner, a pediatrician and member of the American Academy of Pediatrics Committee on Infectious Diseases, said the country is beginning to see the effect of lower vaccination rates in some areas. He also said last year and this year would have been less severe with stronger local health departments and a better-staffed CDC response.

The current wave began building in January 2025 in West Texas, where Dr. Richard Eby, a family medicine doctor at Permian Regional Medical Center in Andrews, treated a child with measles who needed care for dehydration and shortness of breath. Eby said the child’s mother told him a small private school had already canceled classes because many students were sick.

That Texas outbreak grew to 762 cases and included the first U.S. measles deaths in more than a decade, including two young girls. It became the first major surge in a series of outbreaks that have continued into a second year and could affect the country’s measles elimination status, which dates to 2000.

New outbreaks have been reported in Arizona, Delaware and Wyoming. Pennsylvania health officials have reported 132 cases, including 27 diagnosed in the past week.

Virginia’s outbreak, which began accelerating in May, appears to have slowed, according to state health data. The state has recorded 177 cases and has not reported a new case since July 4.

Dr. Maria Almond, health director for Virginia’s Piedmont Health District, said staff members have gone door to door to encourage vaccinations and connect families with care. The district has accounted for most of Virginia’s cases.

Utah’s outbreak, which began in June 2025 in a small community near the Arizona border, has spread across the state, including the Salt Lake City area. The Utah Health Department has reported more than 700 infections to date, including 514 this year.

South Carolina’s Upstate region has also been a major driver of the national increase. Dr. Stuart Simko, a pediatrician at Prisma Health in Greer, said the state outbreak forced clinicians to learn quickly how to identify measles; he described children with high fever, rash and severe fatigue.

Most measles cases have been in children and teenagers, but adults have also become seriously ill. Pennsylvania health officials reported that 39% of cases there have occurred in people under 18.

The Pan American Health Organization is expected to decide in November whether the United States keeps its measles elimination status.

This story draws on original reporting from NBC News.