A patron of the Berkeley restaurant, La Mediterranee, who was measles positive may have exposed hundreds last week, according a CBS San Francisco report.

Public domain image/National Atlas of the United States
Public domain image/National Atlas of the United States

The adult, a San Mateo resident, visited the popular Berkeley restaurant Feb. 20, between 6:45 p.m. and 8 p.m. Health officials say at the time, the person did not have symptoms yet, and was not aware of the infection.

In addition,  San Mateo County Health System confirmed the County’s fourth measles case since the outbreak began in December 2014. People in San Mateo County and neighboring counties may have been exposed to measles while the San Mateo County resident was infectious.

Some BART riders may have been exposed to measles when the San Mateo County resident commuted on February 20th from the Millbrae station (boarding at 4:30 pm) to Civic Center in San Francisco (exiting around 5:00 pm) on a Richmond-bound train. While the risk of contracting measles by being exposed on BART is low, Bay Area residents should be aware and watch for symptoms if they are not vaccinated.

San Mateo County Health System’s Communicable Disease (CD) team is compiling a list of all people the person was knowingly in contact with while contagious, such as family and friends, and a list of public places where the person may have come into close contact with other people, such as workplace, public transportation, restaurants, and other public venues. The person’s employer is fully cooperating with the Health System to ensure the safety of any employees who may have been exposed.

“Measles is a highly contagious disease, a dangerous disease for many people, such as infants, and most important, it’s a preventable disease,” said Dr. Scott Morrow, San Mateo County Health Officer. “The measles vaccine is safe and being vaccinated not only protects you and your family, but every child and person in your community. I strongly urge everyone to get vaccinated and help stop the spread of measles.”

Since December, 2014, there have been 130 confirmed measles cases reported in California residents.