Ongoing measles transmission across more than 30 U.S. states continues to drive weekly case additions, with the CDC reporting 1,842 confirmed cases through May 7, 2026—already approaching last year’s full-year total. Most infections remain outbreak-associated in under-vaccinated communities, consistent with the virus’s high basic reproduction number of 12–18 that enables rapid spread once introduced. Recent additions of 40–90 cases per week reflect both sustained domestic chains and sporadic travel-related importations, while provisional data reconciliation may shift final tallies. The next CDC weekly update and any new state health department reports before May 31 represent the primary near-term data points that could influence market resolution thresholds.