IMMUNIZATION BRANCH
Measles
Measles is a highly contagious viral disease. It is widespread in many parts of the world, including Europe, Africa, and Asia. Measles begins with a fever that lasts for a couple of days, followed by a cough, runny nose, conjunctivitis (pink eye), and a rash. The rash typically appears first on the face, along the hairline, and behind the ears and then affects the rest of the body. Infected people are usually contagious from about 4 days before their rash starts to 4 days afterwards.Measles Activity in California 2025 – As of March 11, 2025
As of March 11, 2025, five confirmed measles cases have been reported in California in 2025. These data are provisional and subject to change.
CDPH will update case counts every two weeks. The next update will be on March 25, 2025.
Table. Reported Measles Cases by Month of Rash Onset – California, 2025
| Month of Rash Onset |
Number of Cases |
|---|---|
| January 2025 | 0 |
| February 2025 | 3 |
| March 2025 |
2 |
Outbreaks
While high levels of immunity in the general population ultimately limit measles outbreaks, measles readily spreads in communities and social networks with lower coverage.
In December 2014–April 2015, at least 131 California residents were infected in a large measles outbreak associated with Disneyland; the outbreak also infected residents of six other states, Mexico, and Canada.
In 2019, there were 73 confirmed measles cases in California, including 41 cases associated with six outbreaks (defined as 3 or more cases). Of the six outbreaks, five were linked to patients with international travel, while one had an unknown source. The largest outbreak consisted of 21 cases and involved multiple generations of transmission in a health care setting. The other five outbreaks involved from 3 to 5 cases.
Case counts for 2012–2017 are available in the Vaccine-Preventable Disease Summaries. Case counts for 2018-2022 are available in the Vaccine-Preventable Disease Annual Report. Four measles cases were confirmed in California in 2023, and 15 were confirmed in 2024.
For information on measles cases and outbreaks nationwide, please see the CDC Measles Cases and Outbreaks.
- CAHAN Health Advisory (February 2, 2024): Fever and Rash? Consider Measles. Traveling Abroad? Protect against Measles.
- CAHAN Health Advisory (March 14, 2024): Immediate Respiratory Isolation Recommended for Persons with Suspected Measles
- Measles Clinical Guidance (PDF)
- All Facilities Letter - Recommendations for Case Identification, Infection Control, and Case and Contact Investigations (PDF)
- IG for Measles Prophylaxis (PDF)
- ACIP Recommendations for the MMR Vaccine
- CDC Measles Outbreak Toolkit for Healthcare Providers
-
Measles - CDC Pink Book
-
CDC Manual for the Surveillance of Vaccine-Preventable Diseases
- Measles Immunization Recommendations - May 22, 2019 (PDF)
If you are having difficulty accessing documents on this page please call 510-620-3737 or email
ImmunizationBranch@cdph.ca.gov to request this information in an alternate format.

