What is the state of measles in California right now?
Five cases of measles have been confirmed in California in 2025, with two of those confirmed so far in March alone.
All of the state’s five 2025 cases were separately reported after international travel, and no link to the outbreak in Texas has been found. The California Department of Public Health defines an “outbreak” as three or more related cases.
“Measles is one of the most contagious viruses in the world, but it is preventable with the MMR vaccine, San Francisco Health Officer Dr. Susan Philip said in a statement. “If children in your family are not fully vaccinated, or if you did not have measles as a child, please get the vaccine for the best protection.”
The last major measles surge in California was in 2019, when 41 cases were associated with six separate outbreaks, bringing the state’s yearly total to 73. The largest outbreak that year resulted in 21 individual measles cases.
Before that, an outbreak associated with Disneyland visits resulted in at least 131 Californians being infected with measles between Dec. 2014 and April 2015.
What is the measles vaccine, and when would I have got it?
Measles is preventable with the combined Measles, Mumps, and Rubella (MMR) vaccine, and vaccination against measles has been part of routine childhood immunization for decades. There’s also a combined Measles, Mumps, Rubella and Varicella, or MMRV, vaccine, but it’s only licensed for use in children under 12 years of age.
The CDC recommends that everyone over 12 months of age be vaccinated against measles, with children receiving two doses of the MMR vaccine starting at 12–15 months of age. The second dose is recommended at 4–6 years of age. This vaccine provides lifetime protection against measles, so if you got your MMR vaccine as a child, you’re considered up-to-date on your vaccine.
If I’m up-to-date on my measles vaccines, do I need a measles booster?
No, the CDC said. If you got two doses of measles vaccine as a child according to the U.S. vaccination schedule, the CDC considers you “protected for life” and that you “do not ever need a booster dose.”
There are, however, two groups of older adults who received childhood measles vaccinations but who should still talk to their health care provider about possibly getting another vaccination:
People born between 1957 and 1969
If you are in this age group, which would make you between 56 and 68 years old today, the Bay Area health officers say it’s likely you only received one dose of the MMR vaccine and “should consider getting a second dose.”
What if you were born before 1957?
According to the CDC, everyone born before this year is presumed to have immunity from measles from a previous infection, given how widespread the virus was during that period — although people in this age group who work in health care and who don’t have any written evidence of this immunity should get the MMR vaccine anyway.
People who received the ‘killed’ measles vaccine between 1963 and 1967
The “killed,” or inactivated, measles vaccine was an earlier formulation of the measles vaccine that was only used for this brief period in the 1960s, for fewer than one million people, the CDC said. Because it was found to be ineffective and replaced with the current live vaccine, people who know they received this particular version of the vaccine “should talk to their health care provider about getting revaccinated” with the MMR vaccine, according to the agency.
“There is no harm in getting another dose of MMR vaccine if you may already be immune to measles (or mumps or rubella),” the CDC said.
The CDC recommends that everyone over 12 months of age be vaccinated against measles, with children receiving two doses of the MMR vaccine starting at 12–15 months of age. The second dose is recommended at 4–6 years of age. (Joe Raedle/Getty Images)
I don’t know if I’m vaccinated against measles. How can I check?
There’s no national organization that maintains Americans’ vaccination records. Ways that the CDC suggests to track down your own records include:
- Ask your parents or caregivers for records of your childhood immunizations (or look in saved documents from your childhood, like baby books).
- Consult a state immunization registry like the California Department of Public Health’s Digital Vaccine Record portal.
- Ask your doctor or public health clinic, but remember that these records may only be stored for a limited time.
The CDC has a guide to tracking down your vaccination records.
According to the Bay Area coalition of public health officers, “your medical provider can order a simple blood test to check whether or not you are immune” from measles, either from vaccination or from a childhood infection.
Another reason to check your vaccination status if you’re unsure: Possessing documentation of your vaccination status “can help you avoid being quarantined if you are exposed,” the health officers said.
And if you can’t find any sign that you or your family have received a measles vaccine.
“Teenagers and adults with no evidence of immunity should be vaccinated right away,” they added — something the CDC echoed.
If I’m vaccinated, am I still at risk of getting measles?
Five years of living with COVID-19 have taught us that being vaccinated against a virus doesn’t necessarily mean you won’t get infected with that virus. The COVID-19 vaccine, for example, does somewhat reduce your chances of being infected — although the CDC said that “protection against infection tends to be modest and sometimes short-lived” — but it also means you’re much less likely to get severely ill if you do get infected.
However, the measles vaccine is incredibly effective at protecting against infections, the CDC said, and two doses of measles vaccine are “about 97% effective” at preventing measles if you’re exposed. (One dose is “about 93% effective.”)
As for why “about three out of 100” people vaccinated against measles will still get measles after exposure — also known as breakthrough cases — the CDC said that experts “aren’t sure why” and that this could be due to the responsiveness of an individual’s immune system to the vaccine.
“But the good news is, fully vaccinated people who get measles seem more likely to have a milder illness,” the CDC said — and fully vaccinated people “seem also less likely to spread the disease to other people.
What are the symptoms of measles?
Measles symptoms can occur between 1 and 3 weeks after exposure and could include fever, cough, runny nose and pink eye, followed a few days later by a rash. (Natalya Maisheva/Getty Images)
Symptoms include fever, cough, runny nose, and pink eye, followed a few days later by a rash. These symptoms can emerge between seven and 21 days after exposure. About 1 in 5 unvaccinated people who become infected with measles — a highly contagious virus that spreads through direct contact with infectious droplets — will require hospitalization, according to the CDC.
In some people, the disease can be fatal. In others, the impacts of an infection can linger — or appear — years afterward.
Before the U.S. measles vaccination program started in 1963, an estimated 3 to 4 million people nationwide were infected with measles annually, the CDC said — with only 500,000 being reported.
“Among reported cases, 400 to 500 died, 48,000 were hospitalized, and 1,000 developed encephalitis (brain swelling) from measles,” the agency said.
Where can I find a measles vaccine in the Bay Area?
If you have health insurance, the CDC’s recommendation of these shots means that your insurer should cover the costs. You can find appointments for an MMR vaccine at:
For those without insurance: Uninsured children ages 18 and under can get free DTaP vaccines — and other no-cost immunizations — as part of the Vaccines for Children Program. People without insurance can get the MMR vaccine at a lower cost — or even free if they qualify for the Vaccines for Adults Program — from several providers and community clinics around the Bay Area, including:
