Respiratory Syncytial Virus (RSV) transmission is continuing in California.
CDPH recommends continuing RSV immunization of eligible infants and young children with RSV monoclonal antibody products through April 30, 2026.
As of 3/7/2026, percent positivity for RSV in Orange County continues to increase week over week.
This health alert is issued to inform healthcare providers about the ongoing transmission in California of Respiratory Syncytial Virus (RSV), the most common cause for hospitalization in infants in the US. As RSV infections are likely to continue into April 2026, CDPH recommends continuing RSV immunization of eligible infants and young children with RSV monoclonal antibody products through April 30, 2026.
Measles is the most contagious diseases known—but the good news is that it is preventable. In response to recent cases reported in Orange County and across the region, the OC Health Care Agency (HCA) encourages both health care providers and community members to take simple, proactive steps to stay protected.
Below is what you need to know to keep yourself, your family, and our community safe.
Why Measles Matters
Measles spreads through the air and can linger after an infected person leaves a room. A single infectious person may expose dozens of people in public settings, including airports, entertainment venues, or even local venues.
Because measles can lead to serious complications—especially in infants, pregnant people, and individuals with severely weakened immune systems—being prepared is essential.
For Community Members: How to Stay Protected
1. Know Your Immunity Status
Everyone who has received 2 doses of MMR vaccine (Measles, Mumps and Rubella) is considered immune.
If you are not sure whether you are protected against measles, check your vaccine records or ask your health care provider.
Most people born before 1957 are generally considered immune.
People who have not received the MMR vaccine or never had measles are not protected and are at highest risk of catching measles.
2. Get Vaccinated if You Are Eligible
MMR vaccination is safe and provides excellent protection:
Children should receive two doses (first at 12–15 months, second at 4–6 years).
Adults born after 1957 should have two documented MMR doses, unless they are immune.
Vaccination is especially important before travel, attending large gatherings, or working in health care or school settings.
Special Note Around Areas with Measles
Those who are in areas with increased measles activity or planning on international travel or travel to areas with measles outbreaks and who are at higher risk (un-immunized, or individuals considered to be immunosuppressed) should consult their health care provider and consider the following:
Teens and Adults without evidence of immunity are advised to get their first dose immediately and their second dose 28 days after the first dose.
Infants 6–11 months old can get an early MMR dose before departure.
Children age 1 and older should get their first dose immediately and a 2nd dose 28 days after their first.
Note: Early MMR dose given at 6-11 months is an additional dose and is not counted as part of the routine two-dose MMR series because it may not produce a durable immune response but can provide a layer of protection for infants going to areas with increased measles activity.
3. Stay Informed
Monitor local updates from either local public health or state public health officials and respond promptly to any calls from Public Health if you may have been exposed to a case. Staying engaged and vigilant helps protect you and those around you. Knowing your immunity status and ensuring vaccination are the most effective tools we have to stop measles from spreading.
About Dr. Anissa Davis Dr. Anissa Davis graduated from UCLA and Stanford University School of Medicine. She completed her family medicine at Long Beach Memorial Medical Center, and is board certified in Family Medicine. She also completed a Preventive Medicine Residency and a master’s degree in public health (MPH). She is the Medical Director for the OC Health Care Agency’s (HCA) Communicable Disease Control Division and Deputy Health Officer for the HCA. She worked in primary care, caring for infants, children and adults for more than 10 years. In addition, she has worked in local public health agencies for a decade.
