Measles case linked to San Francisco airport and San Jose stores prompts exposure alerts
Health officials warned that an infectious measles patient who passed through San Francisco International Airport and two San Jose grocery stores may have exposed others, urging unvaccinated individuals to monitor symptoms and seek medical advice.
Health authorities in California have identified an adult from Santa Clara County who was infectious with measles while traveling through San Francisco International Airport on Thursday morning between 8:30 a.m. and 11:00 a.m., moving through the international terminal, passport control, customs and baggage claim areas. The same individual later visited two San Jose grocery locations, Trader Joe's and International Halal Market, between 8:00 p.m. and 10:00 p.m. on the same day.
Officials said anyone present at those sites during the specified times could have been exposed. Because measles is highly contagious, they reminded the public that symptoms typically appear seven to ten days after exposure and may include fever, cough, runny nose, red eyes and rash. Unvaccinated people are advised to quarantine, avoid large gatherings and monitor for signs of illness for up to three weeks. Pregnant women, infants, immunocompromised individuals and those without vaccination should seek medical guidance immediately if exposure is suspected.
"Vaccination remains the strongest protection against measles and helps prevent widespread outbreaks even when exposures occur," said Dr. Sarah Rudman, Santa Clara County health officer.
The county is working with the California Department of Public Health and the U.S. Centers for Disease Control and Prevention on contact tracing related to the exposure sites. California has recorded 49 measles cases as of June 8, the highest annual total in seven years and nearly double the 2025 count. State data indicate that 94% of cases involve unvaccinated individuals, with more than 80% occurring in people under 19, highlighting gaps in immunity despite generally high vaccination rates in the Bay Area.
The alert follows previous exposure warnings issued by Santa Clara County in February 2026 and May 2025, as measles continues to reappear in the state through international travel and pockets of low vaccination. Nationwide, officials have noted a resurgence of measles, including a major outbreak in West Texas in 2025 that resulted in over 750 cases, dozens of hospitalizations and two deaths among unvaccinated patients.