U.S. measles cases reached 2,318 in 2026, the highest annual total in about 35 years, with authorities including Johns Hopkins and the CDC warning that elimination status could be at risk. A small number of states—led by South Carolina and Utah—account for the majority of infections, with seven states making up more than 84% of cases, while kindergarten vaccination coverage has slipped and herd immunity weakened to around 90% in some areas. Health officials say the outbreak risk remains greatest in communities with low vaccination rates, especially as schools reopen. Experts warn that if vaccination rates do not improve, the U.S. could lose its measles-elimination status, a milestone already questioned by health authorities and international bodies. Local health departments report predominantly unvaccinated cases, with outbreaks expanding in California, Arizona, Missouri, Washington, and other regions, underscoring the need for vaccination and public health measures to curb spread.