Bay Area mask mandates could come 'as early as next week'

Currently, eight of the nine Bay Area counties — along with the state of California — recommend, but do not mandate, that people mask up indoors, whether or not they are vaccinated. Only Solano County has not made this recommendation.

But the situation is changing quickly. Los Angeles, Yolo and Sacramento counties have mandated indoor masks. Bay Area health officials are closely monitoring developments, and Dr. Grant Colfax, San Francisco’s director of health, said on Friday that the city was in discussions with surrounding counties and “very vigorously” looking into a mask mandate — with action expected “as early as next week.”

Here’s where each Bay Area county stands on masks:

Alameda County

“While fully vaccinated residents are well protected from severe illness due to the virus, there is limited emerging evidence that vaccinated people can spread the virus to others,” said Neetu Balram, a spokesperson with the Alameda County Public Health Department. “Coupled with vaccinations, masks provide an additional layer of protection and limit the spread of COVID-19. We’re taking all of this under consideration as we determine whether a mask mandate is needed.”

Contra Costa County

“We are carefully monitoring local transmission data and will notify the public promptly if there is a need to modify or update local health orders,” said Karl Fischer, a spokesperson with Contra Costa County.

Marin County

“We still have not yet changed any recommendations,” said Laine Hendricks, a spokesperson with Marin County. “But given increased case rates both locally and regionally, including breakthrough cases, we are closely monitoring our data and considering it as an option if the data warrants.”

Napa County

No information was available for Napa County.

San Francisco County

Mayor London Breed said this week that the city is considering whether to require masks again until more people are vaccinated and cases decline again. “Yes, we are looking at mask mandates for both vaccinated and unvaccinated,” Breed said.

San Mateo County

“San Mateo County is not considering a mandate for masks or social distancing at this time,” said Preston Merchant, spokesman with San Mateo County Health. “We continue to recommend masking for everyone indoors, regardless of vaccination status, and urge everyone who is eligible to get vaccinated.”

Santa Clara County

No information was available for Santa Clara County.

Solano County

Solano County is the only Bay Area county that hasn’t issued a recommendation that people wear masks. Jose Caballero, a senior health education specialist with Solano County health and social services, said mask rules wouldn’t address the key factors causing cases to rise: private social gatherings and under-vaccinated populations. The public health department is focused on improving vaccine outreach and access for “under-resourced neighborhoods and individuals,” he said. Even so, the county “encourages concerned community members to wear masks indoors if they are unsure of the vaccination status of those they are interacting with for prolonged periods or the unvaccinated.”

Sonoma County

Dr. Sundari Mase, Sonoma County’s health officer, said at a news conference on Wednesday that she was “strongly recommending everyone wear masks in indoor public settings.”

“Because the delta variant is so transmissible, we will keep stressing the importance of masking,” Mase said.

Chronicle staff writers Trisha Thadani, Catherine Ho and Aidin Vaziri contributed to this report.

Julie Johnson is a San Francisco Chronicle staff writer. Email: [email protected] Twitter: @juliejohnson