Measles virus in USA

As of September 10, 2025, the United States has reported 1,454 confirmed measles cases across 37 outbreaks, with 86% of cases associated with outbreaks. The majority of cases have occurred in communities with lower vaccination rates. The Centers for Disease Control and Prevention (CDC) attributes the increase in cases to vaccine hesitancy and disruptions in routine immunization services.

In California, a school-age child died from subacute sclerosing panencephalitis (SSPE), a rare but fatal complication of measles, years after recovering from the infection. This case highlights the severe long-term risks associated with measles in young children. Health officials stress the importance of community immunity to protect those too young for vaccination.

To combat the outbreak, health authorities are intensifying vaccination efforts, particularly in high-risk communities. Public health campaigns are being launched to educate parents about the safety and efficacy of vaccines. The CDC is also working with state and local health departments to improve access to immunization services and address barriers to vaccination.