Measles County confirms first measles case in seven years

Measles have arrived in Riverside County. On April 3, the County Public Health agency reported that an adult county resident tested positive for measles. According to health officials with Riverside University Health System, this is the first confirmed case of measles in Riverside County since 2018. 

As of March 31, the California Department of Public Health reported eight confirmed cases of measles in the state. The infections were found in residents of the following counties: Fresno, Los Angeles, Orange, Placer, San Mateo​, and Tuolumne.

On April 3, the U.S. Centers for Disease Control reported a total of 607 confirmed measles cases have been identified in 22 states.

More than one third of the cases were in Texas. Two unvaccinated children have died. The first occurred in February and the second child, an 8-year-old’s death was reported on April 3.

Nearly three-quarters of the confirmed cases were in children or youth under 20 years. Nearly 97 % were unvaccinated according to the CDC.

In 2024, there were 285 confirmed cases in the U.S., of which 15 were in California. In total, 90 % of those people were unvaccinated

“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 in the press release, which noted that the eastern Riverside County resident has a recent history of international travel.

“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. 

Measles is highly infectious and can be spread through the air via droplets when a person breathes, talks, coughs or sneezes. Symptoms are typically observed 10 to 14 days after exposure to the virus.

Measles begins with a fever that lasts a couple of days, the RUHS press release said describing the course of the infection. It’s followed by a cough, runny nose, conjunctivitis (pink eye) and then a prominent rash is the most visible symptom. The rash usually appears on the face, along the hairline and behind the ears. Then it affects the rest of the body.

Those infected can spread measles about four days before their rash starts to four days afterwards. ​​

The measles-mumps-rubella vaccine provides the best protection against disease and serious illness., according to both the CDPH and RUHS. Most measles cases in the U.S. result from international travel.

Unvaccinated people are at high risk. Roughly 90% of those unvaccinated and exposed to measles will contract the disease. ​

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. 

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. 

To get vaccinated, call 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.  

Through June, the nearest RUHS clinics appear to be in Hemet, Palm Desert, and San Jacinto.