As of March 26, 2026, the Centers for Disease Control and Prevention (CDC) has confirmed 1,575 measles cases among U.S. residents across 32 jurisdictions, plus nine among international visitors, marking one of the worst starts to a year since measles elimination in 2000. Driving this surge are 16 new outbreaks in 2026, with 94% of cases outbreak-associated—many spilling over from late-2025 clusters in states like South Carolina—and 92% among unvaccinated or unknown-status individuals, amid vaccination coverage below the 95% herd immunity threshold in affected communities. Hospitalizations stand at 5%, with no deaths reported. Traders should watch weekly CDC surveillance updates and Morbidity and Mortality Weekly Reports (MMWR) for case trajectories, as intensified public health responses could curb transmission later in the year.