Sustained community transmission from multiple ongoing outbreaks continues to drive new U.S. measles cases, with the CDC reporting 1,842 confirmed infections through May 7, 2026, across 40 jurisdictions and 25 new outbreaks this year. Most cases remain linked to unvaccinated or under-vaccinated clusters, primarily among children and adolescents, while travel-related introductions sustain spread. Official CDC surveillance data, updated weekly, show recent additions of 40–80 cases per two-week period, reflecting both active outbreaks and improved reporting. With summer travel increasing and resolution tied to cases confirmed by May 31, traders monitor CDC briefings for final tallies, noting that historical elimination thresholds require under 1 case per million residents annually.