Ongoing measles transmission in 2026, driven by declining MMR vaccination coverage below the 95% herd immunity threshold in many communities, has produced 2,903 confirmed cases as of August 27 according to CDC data, already exceeding the full-year 2025 total of 2,289 and marking the highest annual figure since 1991. Over 94% of cases involve unvaccinated or unknown-status individuals, with 94% outbreak-associated across 37 new clusters in 47 jurisdictions; pediatric age groups (5–19 years) account for 47% of infections, and 8% of patients have required hospitalization. Weekly CDC surveillance releases and any final adjudication of reported Pennsylvania measles-associated deaths will provide near-term updates, while the November PAHO review of U.S. elimination status—held since 2000—could influence public health responses and case trajectories through year-end.