ATLANTA—The United States has reported more than 2,100 confirmed measles cases in 2026, bringing the national total to within reach of last year's record-setting figure with roughly half the year remaining, according to the U.S. Centers for Disease Control and Prevention (CDC).
CDC data showed 2,104 confirmed cases as of June 18, compared with 2,288 cases reported during all of 2025, the highest annual total recorded in the United States since 1991. Health officials and infectious disease experts have warned that the country is likely to surpass last year's total if transmission continues at its current pace.
The agency said confirmed infections have been reported across more than 40 U.S. jurisdictions, with most linked to ongoing outbreaks rather than imported cases. About 93% of infections have occurred in people who were unvaccinated or whose vaccination status was unknown, while approximately 72% have involved children and adolescents aged 19 years or younger.
The CDC continues to emphasize that two doses of the measles, mumps and rubella (MMR) vaccine provide strong protection against measles and remains the most effective way to prevent infection and limit outbreaks. The agency has also urged travelers to ensure they are fully vaccinated before international travel, as imported infections can ignite transmission in communities with lower vaccination coverage.
Public health officials have linked the resurgence to declining childhood vaccination coverage in some communities. CDC data show national MMR coverage among U.S. kindergartners has fallen below the 95% level generally considered necessary to maintain community immunity, increasing the risk of outbreaks when the virus is introduced.
While several large outbreaks have slowed or ended, new clusters continue to emerge. South Carolina declared its major outbreak over in April after nearly 1,000 cases, but other states, including Utah and Virginia, have continued reporting significant numbers of infections in recent months.
Health experts have warned that measles remains one of the world's most contagious viruses and can lead to serious complications, including pneumonia and encephalitis, particularly among young children and immunocompromised people. Hospitalizations have been reported in about 6% of confirmed U.S. cases this year, according to CDC surveillance data.
Federal and state health authorities said they will continue monitoring outbreaks and updating national case counts through the remainder of the year as vaccination campaigns and contact-tracing efforts continue.
