Overview
- Napa County confirmed measles in an unvaccinated child who became ill after travel to South Carolina, with officials saying there is no current threat to the general population and urging MMR vaccination.
- Santa Clara County reported a Jan. 10 wastewater detection of measles RNA in the Palo Alto sewershed, with follow-up samples negative and the source unknown.
- Maricopa County confirmed two additional cases, including one with no known exposure source, identified public exposure sites in Gilbert, and recommended early MMR for infants 6–11 months in the local outbreak setting.
- The CDC has logged 416 U.S. cases so far in 2026 across 14 states, with most tied to outbreaks that began in 2025 and the largest share of cases among children and adolescents.
- CDC scientists are sequencing measles genomes to determine if transmission has been continuous; CDC deputy Ralph Abraham downplayed the significance of potentially losing elimination status, while HHS is providing $1.5 million to support South Carolina’s response.