Health officials say there have been 15 cases of the measles statewide so far this year. That's compared to two confirmed cases this time last year.
Of the 15 cases, one is in Alameda County, another is in San Mateo County, and two are in Contra Costa County.
One of the Contra Costa County cases is a UC Berkeley student who may have exposed other BART passengers riding between the Downtown Berkeley and El Cerrito del Norte stations from February 4 through February 7.
At first the student thought he had a simple cold, but lab tests revealed he had measles. Health officials say he was not vaccinated and was probably infected while traveling in Asia.
Health officials say 35 more people in California died from the flu last week. That means there have been 278 deaths statewide this season.
(The Associated Press contributed to this report)