Bay Area officials say scores of commuters and other residents may have recently been exposed to measles after a UC Berkeley student who has the virus attended classes and took public transit.
The student, who was not identified, took a Bay Area Rapid Transit train from his home in Contra Costa County to the college campus to attend class, officials said.
"Measles is a serious, highly contagious disease," said Berkeley's health officer, Dr. Janet Berreman. "It spreads through the air, when an infected person coughs or sneezes. Fortunately, the measles vaccine is highly effective in preventing infection."
In a news release posted on the city of Berkeley's website, officials said they believe the student was not vaccinated and likely contracted measles during a recent trip abroad.
"Before being diagnosed, the student spent time in the Berkeley community, including attending classes and using BART on several days," according to the news release.
Anyone who shows symptoms should immediately see a health professional, officials said.
Symptoms, which can begin one to three weeks after exposure, can include high fever, watery red eyes and a rash that often occurs on the person's face and neck a couple days after the fever starts before spreading to the body.
Officials said that because the measles virus can stay airborne for up to two hours, anyone who used BART from Feb. 4 to Feb. 7 during the morning and late evening commutes may have been exposed.
So far, no other cases have been identified, but officials said they are still investigating the situation.