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Your questions about masking answered by Dr. Naveena Bobba

To mask or not to mask? That’s been the question since Bay Area counties banded together to urge residents to wear masks indoors earlier this month in response to the rising prominence of the COVID-19 Delta variant. The urging came just a month after the state of California did away with mask mandates for vaccinated individuals in most settings.

 “Out of an abundance of caution, people are recommended to wear masks indoors in settings like grocery or retail stores, theaters, and family entertainment centers, even if they are fully vaccinated as an added layer of protection for unvaccinated residents,” read a joint statement from Alameda, Contra Costa, Marin, San Francisco, San Mateo, Santa Clara and Sonoma counties. 

San Mateo has since upped their mask recommendation to a requirement at its county facilities. And today, the CDC recommended—in a marked reversal—that vaccinated people in areas with “substantial” or “high” transmission of COVID-19 mask indoors.  

But what does all this mean for San Francisco, which according to the CDC’s COVID Data Tracker is experiencing a “high” level of community transmission?

We video chatted with Dr. Naveena Bobba, Deputy Director of San Francisco’s Department of Public Health, to demystify what the latest local mask recommendation means for those vaccinated and unvaccinated.

Here/Say: What is San Francisco’s current stance on masking indoors?

Dr. Bobba: San Francisco’s current stance on masking is that if you’re unvaccinated, you must wear a mask indoors, and if you are vaccinated, it is recommended to wear a mask indoors.

Here/Say: Why recommend vaccinated people wear masks indoors rather than require them to? 

Dr. Bobba: Unvaccinated individuals are required to mask indoors based on CDC and CDPH [California Department of Public Health] guidelines. 

The recommendation to mask indoors for vaccinated people is a local recommendation, a Bay Area recommendation, and that is based on the fact that we are seeing increases in case rates across the Bay Area. So it is a way to see if that recommendation will help turn the curve on the rise in COVID cases. 

Here/Say: Is the indoor masking recommendation mostly to protect those who are unvaccinated? 

Dr. Bobba: Yes, it’s mainly to protect the unvaccinated people around you, but also we do know because the Delta variant is highly transmissible, that there are vaccinated people that are going to get this disease. It will be mild. But if you want to protect yourself against the disease, then it’s reasonable, even if you’re vaccinated, to mask indoors.

Here/Say: How does this mask recommendation impact indoor dining?

Dr. Bobba: This mask recommendation for vaccinated and unvaccinated [people] does not impact indoor dining in the terms that you can still go into a restaurant, and if you’re eating, you can be unmasked. But the recommendation is to mask when you’re not eating.

Here/Say: What about other businesses? Could they have a requirement that you mask indoors regardless of your vaccination status?

Dr. Bobba: Businesses can require people mask indoors for their business. So different businesses have dealt with this differently. Some businesses have signs up saying if you’re coming into our store, you need to mask up. Some businesses are doing that [self]-attestation, saying if you’re vaccinated, you can come in unmasked. But if you’re unvaccinated, you need to mask, and kind of letting the customer decide which group they fit into. 

A hairdresser cuts hair for a customer at a San Francisco barber's shop in 2020. | Photo by Liu Guanguan/China News Service via Getty Images

Here/Say: With the Delta variant on the rise, do you foresee San Francisco potentially making masking mandatory soon, like in counties such as Los Angeles?

Dr. Bobba: We are following the data very closely right now. Our case rates are going up. But the good thing is our hospitalizations, while they’re going up, they’re going up at a much slower rate. And so that is something that we’re keeping a close eye on. One of the reasons that we want people to mask up is to really turn the curve on the case rates. 

So generally in terms of recommendations versus mandates, we do need to see if our recommendations change the course of this. And that usually takes a little bit of time. 

Here/Say: What change have you seen since you put the mask recommendation out?

Dr. Bobba: I don’t have any hard data on that. But just anecdotally, when I go into indoor spaces, there does appear to be more people masking. People in San Francisco in general actually are pretty good about masking, but it does seem like there are definitely more people masking indoors in grocery stores. 

Here/Say: How concerned should San Franciscans be about the Delta variant?

Dr. Bobba: Most of San Francisco is vaccinated, and that’s great. We are seeing rising cases, but probably we would have seen a much higher proportional rise if we didn’t have such a great vaccination rate. We do have concern because COVID and the Delta variant are definitely spreading, and it’s much more transmissible compared to the previous variants and iterations of COVID. So I think there’s some concern. I don’t think there’s any need for panic, and I think there are definitely tools within our reach and the public’s reach and all of your reach to change this curve. And that includes simple things that people have been doing throughout this pandemic, including, again, masking, testing and getting vaccinated. All of those things will help turn this curve.

Here/Say: Who’s impacted the most by the Delta variant and the coronavirus surge in San Francisco?

Dr. Bobba: So the people that are most impacted by the Delta virus are the people that remain unvaccinated. We do see a huge, disproportionate number of cases in the unvaccinated at this point in time. And we are seeing an increase in case rates in our Black African-American population as well as our Latinx/Latina/Latino population as well. We’re taking [this] very seriously and doing more outreach efforts with our community partners to try to get the word out about vaccines as well as masking and testing. 

I will say the other place that a lot of people are concerned about is there is a group of people that are not able to get vaccinated right now, those under 12. 

Here/Say: Should adults be masking up around children, especially young children who may be unvaccinated or under the age of 12? 

Dr. Bobba: Yes, absolutely, and that’s one of the reasons, especially in youth settings, that masking is recommended because they do remain unprotected. And generally what we’ve seen in our school system, in our child care system, if everybody’s masked up, there generally is low transmission and especially if the adults are vaccinated. So that’s another great way to protect our children. 

Here/Say: So when in doubt should you just bring a mask with you? 

Dr. Bobba: You should definitely be prepared to mask. And I will say that is not only to protect others, but also to protect yourself. There is good evidence that it’s not just about transmitting potentially asymptomatic disease or, if you have mild symptoms, transmitting it to others, but also it can also help protect you against getting [COVID]. So I think most of us in public health, as well as in the medical world, are starting to mask up indoors.

Here/Say: Anything else San Franciscans should know? 

Dr. Bobba: San Francisco, you’ve gotten us all the way here. We’re just almost at the homestretch, hopefully. And so, we can get over that line together. 

Visit or the San Francisco Department of Public Health’s website for updates should city masking recommendations and COVID protocols change.

Mike Kuba can be reached at