Riverside County Reports First Measles Case Of 2026

Public health officials Monday announced the first reported case of measles in Riverside County this year in a child between the ages of 5 and 8.

Riverside University Health System — Public Health (RUHS-PH) officials said the Western Riverside County child, who was recovering at home, had no recent history of international or out-of-state travel and was not vaccinated.

“As we see growing reports of measles from our neighboring counties, the risk of measles is no longer remote,” Riverside County Public Health Officer Dr. Jennifer Chevinsky said in a news release. “It’s now also impacting us here in our own county, even among those with no recent international or out-of-state travel. The importance of timely vaccination is clear.”

Barbara Cole, director for disease control with RUHS-PH, said in an interview with The Riverside Record that the county was investigating how the child contracted the virus, but had not identified any other cases within the county. She also said the county had not identified any other locations in the county where others might have been infected.

“This individual is home recovering, and really is doing well, expected to make a full recovery, but we do indeed encourage parents to consider vaccination of their children,” Cole said. “It’s a very serious disease in some people, so vaccination is key to prevention.”

Health officials recommend children receive one dose of the MMR (measles, mumps, rubella) vaccine at 12 months and another between the ages of 4 and 6 for standard protection. For those between 6 and 12 months of age, a dose of the vaccine is recommended prior to international travel to reduce the risk of contracting the virus.

Older children, teens and most adults who have not been vaccinated, two doses separated by at least 28 days should be given to provide protection, especially before travel to areas with known measles transmission. According to the California Department of Public Health (CDPH), two doses are 97% effective against measles and provide the best protection against disease and serious illness.

Signs of measles are typically observed 10-14 days after exposure to the virus and include a prominent rash and fever followed by a runny nose, cough and pink eye. More severe symptoms can include pneumonia and brain swelling. Those infected with the virus can spread measles roughly four days before the rash starts to four days after.

“Measles is highly infectious and can be spread through the air when a person breathes, talks, coughs or sneezes, so it is very important to call your healthcare provider if you may have been exposed and especially at the first sign of measles illness,” Dr. Chevinsky said. 

Monday’s reported case is part of a wider reporting of cases in Southern California, including confirmed cases in Orange, San Bernardino and Los Angeles counties. As of February 2, there were nine cases of measles confirmed this year, according to CDPH. 

Last year, Riverside County reported its first case of measles since 2018. Cole said that person had traveled to an area with measles activity. Between 2001 and 2025, the county reported 20 total cases of measles, according to California Health and Human Services data.

“As a state, measles is close to being considered eradicated,” Cole said. “But then you have these upticks where people go to other places, where there’s lots of measles, they can become ill, come back and expose others, so it depends on what’s happening around us, not just what’s happening in our county.”

RUHS-PH has more information about measles, including answers to frequently asked questions about vaccination and treatment, on its website here.