As of July 30, 2026, the CDC has confirmed 2,371 measles cases in the United States for the year, already exceeding the full-year 2025 total of 2,289 and marking the highest annual count in over three decades. The primary driver of current trader sentiment is sustained transmission within 37 outbreaks, with 94% of cases linked to these clusters—primarily among unvaccinated or under-vaccinated communities where MMR coverage falls below the 95% herd-immunity threshold. Official surveillance shows most cases concentrated in a handful of states, fueled by domestic spread rather than imports. With roughly 30 days remaining until August 31, weekly CDC case-count updates and state health department reports on new outbreaks or vaccination campaigns represent the key near-term data releases that could shift implied probabilities, especially if case incidence accelerates or containment measures gain traction.