All but one Bay Area county will no longer enforce a public indoor mask mandate on Wednesday when California's requirement expires. Yet state data released on Monday shows regional COVID-19 cases are no longer declining in the region.
The San Francisco Chronicle reported on Monday that the Bay Area averaged 86 new cases per 100,000 residents, up from 60 per 100,000 a week prior. Although the California Department of Public Health said a backlog of almost 27,000 confirmed cases could've been responsible for the variance, the increase was enough for Dr. John Swartzberg, an infectious disease expert in UC Berkeley's School of Public Health, to label decisions to lift mask mandates in the region "premature."
"I think it was premature to do this," Swartzberg told KCBS Radio's Margie Shafer in an interview on Tuesday morning. " ... It's been so wonderful to see the dramatic drop in the number of cases from the horrible surge that we've been through, but there's no written law in nature that says this is going to continue."
California's latest data approximating the rate of infection, estimated as the number of people an infected person will pass the virus to, no longer decreasing in parts of the Bay Area.
Alameda, Marin, San Francisco and San Mateo counties' effective reproduction numbers, or "R-effective," on Feb. 13 – the latest day for which data is available – showed the rate of infection increasing ever so slightly in recent days.
In three counties, that means the spread of COVID-19 is estimated to be decreasing at a slower rate. In San Francisco, with an R-effective of 0.93, that means the spread of COVID-19 is "likely stable" rather than "likely decreasing" as it is in every other Bay Area county.
"The really rapid descent that we've been seeing over the last few weeks may be slowing a little bit right now," Swartzberg said. "Looking at the average over the last week, it looks like it's starting to level off in some of the Bay Area counties, and that's disturbing."
Swartzberg said counties lifting their mask mandates should have waited a few more weeks to do so, in order to see if cases rapidly declined once more.
Santa Clara County, the Bay Area's lone holdout, is doing just that. Officials said will be monitoring COVID-19 hospitalizations and case rates. If those metrics continue declining, it could be a matter of weeks before masks aren't required in Santa Clara County's public indoor spaces, either.
In the meantime, Swartzberg said he would continue to wear a mask – a surgical mask "at minimum," or, preferably, a KN95 or N95 – in public indoor spaces and crowded outdoor ones, a la Super Bowl LVI.
"We're really talking about a couple weeks, maybe three weeks if the descent starts again," Swartzberg said, advising Bay Area counties to keep their mask mandates in place. "But let's make sure we're where we want to be before we take these masks off."
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