San Francisco Reports First Measles Case Since 2019 in Unvaccinated Infant
San Francisco health officials confirmed the city's first measles case in seven years, involving an unvaccinated infant under 12 months old who was exposed while traveling internationally. The case highlights ongoing concerns about measles outbreaks across California and the importance of vaccination for international travel.
First SF Measles Case in Seven Years
San Francisco Department of Public Health confirmed a measles case in an unvaccinated infant under 12 months old on Monday, April 15, 2026. The child was exposed to measles while traveling internationally and became infectious after returning to the Bay Area.
Current Status:
- The infant is recovering at home
- All household contacts are vaccinated
- Health officials are conducting contact tracing for close contacts outside the home
- Risk to general public deemed low
Part of Broader California Outbreak
This case comes as California battles one of its worst measles outbreaks since 2019, with 39 confirmed cases statewide as of April 2026. Sacramento and Placer counties are experiencing ongoing outbreaks with at least 19 cases.
Vaccination Recommendations:
- MMR vaccine typically given at 12-15 months, with second dose at 4-6 years
- Early vaccination available for infants 6-11 months traveling internationally
- Health officials emphasize measles as "one of the most infectious diseases in the world"