Measles cases have doubled in California so far this year compared to last year – and 2026 will almost double.
California has confirmed 52 cases of measles in the first 6½ months of the year; that’s more than double the 25 cases reported in all of 2025. If this pace continues, the number of cases in California will be the highest since 2015, when there were 125 cases in the state and half of them were related to the large outbreak at Disneyland.
Of the 52 cases this year, 49 patients were unvaccinated or had an unknown vaccination record. Four had to be hospitalized. Most of the cases involved children or young adults — 27 cases involved those ages 5 to 19, and 15 cases involved children younger than 5 years old, according to the California Department of Public Health. LA County has tallied seven cases so far this year among its own residents.
Nationally, measles cases have nearly surpassed last year’s total and the country is poised to hit its highest rate since the late 1980s and early ’90s. Since mid-July, 2,260 people with measles have been reported, compared to 2,289 last year. Last year’s figures were the highest in a single year since the devastating measles epidemic of 1989-91, which resulted in more than 55,000 cases and 166 suspected deaths.
The US Centers for Disease Control and Prevention stated that 93% of confirmed cases of measles are associated with outbreaks. 34 new outbreaks have been reported so far this year.
New cases of measles continue to be reported across California at a steady clip, putting unvaccinated people — including children too young to receive their first vaccination — at risk of severe illness and possible death.
A recent case involved a minor who lived abroad and now lives in Orange County; The child contracted measles while traveling through Los Angeles International Airport, officials said.
The child arrived on a flight from Cancun, Mexico, on Delta Air Lines Flight 614 on July 16 at 9:45 p.m., the Los Angeles County Department of Public Health said. Mexico is among the top 10 countries in the world with measles outbreaks, according to the World Health Organization.
People who may have been exposed to an infected passenger include those who were at the international terminal, near Gate 206, about an hour after the flight arrived, and the baggage claim area between 10:30 pm and 11:30 pm.
Passengers who were seated near an infected passenger, as well as people exposed to the person in a health care setting, will be contacted about their exposure, Los Angeles County and Orange County public health officials said. People are susceptible to measles from seven to 21 days after their exposure; The last day to monitor symptoms is August 6.
Unvaccinated people are at high risk of contracting measles and should monitor their symptoms, officials said. Those who have been vaccinated, or have previously been infected, may be protected from infection “but should still watch for symptoms,” the LA County Department of Public Health said.
“As measles cases increase, it is important that citizens take steps to ensure they are fully protected. The MMR vaccine is the safest and most reliable way to prevent measles and protect yourself, your family, and your community,” said Dr. Muntu Davis, LA County health officer, in a statement. “Measles spreads easily and can lead to serious complications, including pneumonia, brain swelling, and even death.”
Another contagious traveler passed through LAX when he contracted the measles earlier this month. The traveler arrived on British Airways flight 281, from London, at Gate 155 of the international airport on July 3. People at that gate between 3pm and 4pm may have been infected with measles, as well as people who boarded the Hertz rental shuttle between 3:30pm and 4:30pm.
There have been at least two newborns infected with measles so far this year in California – both of whom traveled internationally before becoming ill. One case was reported in San Francisco, and the other in Orange County. These infants may have been exposed to measles “during international travel, whether on airplanes, planes or otherwise while abroad,” the Department of Public Health told The Times. “Some but not all have visited an area with a known measles outbreak.”
As of 2020, the state’s Department of Public Health has received 11 reports of infants under one year old with measles. Of these, eight had traveled internationally and one went to another region where the measles outbreak occurred.
“Infants under one year old can get measles, especially during travel,” said the LA County Department of Public Health.
The other two cases involved newborns who had never walked before contracting the virus.
Los Angeles County health officials advise that infants ages 6 to 11 who will be traveling internationally, or domestically traveling to areas with measles, get the early measles vaccine, usually given after the child turns 1, and again between 4 and 6 years of age.
California health officials also recommend that 1- to 3-year-olds get their second dose of measles vaccine early if they will be traveling internationally.
“Parents can consider several factors when deciding about travel, including whether measles is circulating at their destination, the likelihood of exposure during the trip, and whether their child is eligible for an early dose of MMR,” the California Department of Public Health told The Times. “Talking to a pediatrician can help families think about this and choose what makes sense for their situation.”
If parents decide to give their children the measles vaccine, they should try to get the shot at least two weeks before the trip.
When the measles vaccine is given at 6 months of age, 76% develop antibodies to protect against measles, and when given at 8 to 9 months, 85% develop antibodies, according to UC San Francisco infectious disease expert Dr. Peter Chin-Hong. “This is in contrast to infants 12 months and older, where more than 95% develop protective antibodies.”
“Measles does not only affect people who travel or live in other countries—everyone is at risk if they are not protected,” said Dr. Anissa Davis, Orange County deputy health officer. “Because measles is highly contagious, it can spread quickly in communities, even among those who have never traveled.
Health officials are encouraging parents to plan now to renew their children’s vaccinations, with the new school year just weeks away.
“The increase in measles nationally is a reminder that we cannot stop monitoring serious and highly contagious diseases,” said Dr. Susan Philip, San Francisco’s health chief, in a statement.
