Health Officials Report First Confirmed Measles Case in Riverside County
Thursday, April 3
A Riverside County resident has tested positive for measles, according to health officials with Riverside University Health System — Public Health (RUHS - PH). It is the first confirmed case of measles in Riverside County since 2018.
The adult, who has a recent history of international travel, lives in eastern Riverside County and is recovering at home. Documented measles vaccination could not be confirmed at this time.
This is the ninth confirmed measles case in the state, with the remaining eight cases found in Fresno, Los Angeles, Orange, Placer, San Mateo and Tuolumne counties, according to the California Department of Public Health. Recent international travel has been an important risk factor in the 2025 California measles cases.
"Those who travel internationally to areas with ongoing measles transmission may be at risk for exposure. It’s important to check and make sure you are up to date on your vaccines, at least two weeks prior to international travel," said Riverside County Public Health Officer Dr. Jennifer Chevinsky.
Vaccination with one dose of MMR (measles, mumps, rubella) vaccine is recommended as an early dose for infants as young as 6 months old prior to international travel to reduce the risk of contracting measles while in countries where measles is spreading.
For standard measles protection for children, one dose of MMR vaccine should be given at 12 months of age and another at 4 to 6 years.
For older children, adolescents and most adults without documented doses of MMR vaccine, two doses separated by at least 28 days should be given to provide protection. However, for adults born after 1957, one dose of live measles vaccine is sufficient to be considered protected from measles.
All adults who are going to be in a setting that poses a higher risk for measles transmission (e.g., healthcare providers, people traveling to areas with measles) should make sure they have had two doses separated by at least 28 days.
Measles is highly infectious and can be spread through the air via droplets when a person breathes, talks, coughs or sneezes.
The CDC recommends travelers monitor their health for signs and symptoms for three weeks after they return home. Those who develop symptoms, or believe they may have been exposed to measles, are urged to contact their health provider.
"As measles cases continue to occur nationwide, it's important to remain proactive to identify signs of illness, particularly when coming back from international travel, in order to promptly diagnose measles and prevent additional exposures," said Dr. Chevinsky.
Symptoms are typically observed 10 to 14 days after exposure to the virus. A prominent rash is the most visible symptom.
Measles typically begins with a fever that lasts a couple of days, followed by symptoms such as runny nose, cough, conjunctivitis (pink eye) and rash. The earliest symptoms usually last four to seven days.
The rash will usually appear first on the face, along the hairline and behind the ears. It then spreads to the rest of the body. Those infected can spread measles about four days before their rash starts to four days afterward.
Given the risk of rapid disease spread, early identification of illness and staying home while sick is a best practice. This helps protect young children under 6 months of age who are too young to be vaccinated, pregnant women who are at risk for severe disease, as well as those who have immunocompromising conditions.
To get vaccinated, talk to your healthcare provider or visit one of Public Health’s upcoming vaccine clinics. All clinics accept walk-in appointments. Cost and eligibility vary. For questions and clinic locations, please call (951) 358-7125 or visit www.ruhealth.org/vaccineclinics
You can also check for recommended vaccines prior to travel here.
Learn more about measles here.
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