Overview
- California's year-to-date measles count has reached 39, driven by an active Sacramento and Placer County cluster now at 17 cases.
- State health leaders said the Sacramento-area outbreak will likely keep generating exposures for another 21 days because that is measles' incubation window.
- Children and teens account for 85% of cases, and 95% of patients were unvaccinated or had unknown status, with two hospitalizations reported.
- The Sacramento outbreak began with an unvaccinated toddler who returned from South Carolina, linking local spread to large outbreaks tied to travel.
- Earlier this year, Riverside and Shasta counties recorded small outbreaks, while the CDC now counts more than 2,200 U.S. cases across at least 48 outbreaks.