Measles cases in California have surged in the first half of 2026, with 52 confirmed infections reported by mid-July, more than double the 25 cases recorded during the same period last year. This upward trend raises concerns that the state may approach or surpass its highest measles incidence since 2015, when a significant outbreak linked in part to Disneyland led to 125 cases. The majority of recent patients—49 out of 52—were either unvaccinated or had unknown vaccination status, with four requiring hospitalization. Children and young adults comprise a significant portion of cases, including 27 individuals aged 5 to 19 and 15 children under 5, according to the California Department of Public Health. Los Angeles County has reported seven cases among residents so far this year.
The rise in measles cases mirrors national trends, as the United States is on track to reach its highest annual total since the early 1990s. By mid-July, 2,260 cases had been reported nationwide, nearly matching last year’s 2,289 cases. The U.S. Centers for Disease Control and Prevention states that 93% of confirmed cases are linked to outbreaks, and 34 new outbreaks were identified recently. The 1989-1991 epidemic remains the most severe in recent history, with over 55,000 cases and an estimated 166 deaths.
Health officials emphasize the heightened risk to unvaccinated individuals, including infants too young to receive routine immunization. Notably, at least two infants under one year of age have contracted measles this year in California, both following international travel. Since 2020, 11 cases among infants have been reported statewide, with most linked to international travel while some contracted the virus domestically. The California Department of Public Health advises early vaccination for infants aged 6 to 11 months who will be traveling internationally or to regions with active measles outbreaks. This vaccine dose is recommended ahead of the standard immunization schedule, which typically begins at 12 months of age, followed by a second dose between 4 and 6 years old.
Recent measles cases have also been tied to travelers passing through Los Angeles International Airport. One case involved a child who arrived from Cancún, Mexico—a country currently experiencing a significant measles outbreak—who was contagious during their time in the airport’s international terminal and baggage claim areas in mid-July. Additionally, an infectious passenger arrived from London earlier in the month, potentially exposing individuals at the airport’s international terminal and nearby shuttle services.
Public health officials continue to stress the importance of vaccination as the most effective measure to prevent measles, urging residents to ensure they and their families are fully immunized. Measles is highly contagious and can result in severe complications, including pneumonia, encephalitis, and death. Monitoring for symptoms typically begins 7 to 21 days after potential exposure, with heightened vigilance advised through early August for recent contacts at LAX and other exposure points.
Health authorities recommend that parents consult with pediatricians regarding early vaccination and travel plans, particularly in light of ongoing outbreaks internationally and domestically. While immunized individuals have a strong likelihood of protection against the virus, health officials advise them to remain alert for symptoms as well, given the contagious nature of measles.