Health officials in Santa Clara County have issued a warning after a person with an infectious case of measles traveled through San Francisco International Airport and later visited two locations in San José, raising concerns about potential exposure to the highly contagious virus.
According to the county’s Public Health Department, the individual was present in the international terminal at SFO on Thursday morning between 8:30 a.m. and 11 a.m., including time spent in passport control, customs, and the international baggage claim area. Later that evening, from approximately 8 p.m. to 10 p.m., the person visited a Trader Joe’s grocery store at 635 Coleman Avenue and the International Halal Market located at 960 East Santa Clara Street in San José. The public health agency has not disclosed additional identifying details, citing medical privacy considerations.
Officials emphasized that anyone who visited these locations during the specified times could be at risk of developing measles within seven to 10 days following exposure. The department urged unvaccinated individuals, particularly those who may attend large gatherings or travel, to be vigilant and consider quarantine measures to prevent further transmission.
“Exposures like this one highlight the importance of vaccination,” said Dr. Sarah Rudman, Santa Clara County’s health officer and public health director. She noted that the Bay Area benefits from strong community immunity due to high vaccination rates and prior childhood exposure in earlier decades. Rudman reiterated that the most effective protection against measles is receiving two doses of the MMR or MMRV vaccine, which can halt outbreaks when adequately administered.
The health department advised that individuals who might have been exposed should verify their vaccination status by checking immunization records and monitor for symptoms such as fever, cough, runny nose, rash, or red eyes for up to three weeks post-exposure. Those developing symptoms are instructed to contact healthcare providers in advance to minimize the risk of spreading the virus in clinical settings.
Particularly vulnerable groups, including pregnant women, infants, unvaccinated persons, or those with weakened immune systems, are urged to seek immediate medical advice. The department also discouraged attendance at large gatherings during this incubation period, highlighting measles as one of the most infectious diseases globally.
Santa Clara County officials are collaborating with the California Department of Public Health and the Centers for Disease Control and Prevention to conduct contact tracing and containment efforts. As of June 8, California has reported 49 confirmed measles cases this year, with 94% occurring in unvaccinated individuals and over 80% involving those under 19 years old.
While the Bay Area maintains robust vaccination coverage, public health authorities continue to express concern about localized communities with lower vaccination rates due to factors such as vaccine hesitancy or religious exemptions. The county has dealt with similar exposure warnings in recent years, including incidents in February 2026 and May 2025.
These developments come amid broader national concerns following a significant outbreak in West Texas in 2025, where more than 750 cases were reported over eight months, resulting in numerous hospitalizations and two fatalities among unvaccinated residents. The current advisory reinforces ongoing efforts to prevent the reemergence of measles through vaccination and public awareness campaigns.