San Francisco Chronicle - (Sunday)
Bay Area virus surge could be leveling off
children for how to do a pandemic in the United States,” said Dr. Robert Wachter, chief of the Department of Medicine at UCSF. “The vaccine rates are by a fair amount the highest in the country among major metropolitan areas. There seems to be relatively little pushback on masking. And yet the turnaround is slower than we would have expected in the prior surges.”
Experts say the return of many mitigation requirements that had been lifted with California’s June 15 reopening, paired with the cautious behavior of residents in the face of the highly contagious delta variant, is slowing the spread of the virus in the Bay Area. A Chronicle analysis shows the rate of new cases leveling off in San Francisco, Marin and San Mateo counties, which will lead to a dip in the number of people in hospitals in the coming weeks. Other Bay Area counties may also be leveling off, but there is no clear trend.
“There’s always been a lag between what we do and the effects of what we’re doing,” said Anne Liu, an infectious disease doctor at Stanford University. “I do think that we are starting to see some of the effects of people taking precautions again. Case counts are coming down or starting to plateau in some areas. Hopefully, we will see that reflected in hospitalizations soon.”
The return of an indoor mask mandate and the rollout of vaccination requirements for a variety of businesses, in particular, are making an impact in keeping cases at manageable levels — unlike in other parts of the United States such as Mississippi, Florida and Louisiana, where weekly new cases have reached the 100s per 100,000 and hospitals are at capacity.
Yet numbers in the Bay Area are still far above the ratio of fewer than 5 daily cases per 100,000, which is considered a safe level of community transmission by the U.S. Centers for Disease Control and Prevention.
“I think the relatively slow and sluggish descent in the case rates in the Bay Area is because we are fighting a hardier foe now than we were in the prior surges,” Wachter said. “We are doing the same things we did before with many, many more people vaccinated. It’s going to work. But it’s going to take longer, and we may need to do a little bit more.”
He thinks some strategies we may need to adopt are doublemasking, wearing face coverings outdoors when around others and avoiding some activities that may have been deemed safe with prior variants.
It is possible case rates “will spike again” as they did in the heavily vaccinated U.K., Wachter said, if people in the Bay Area become too lax against the delta.
And some fear we may not achieve a comfortable level of immunity until vaccination uptake increases significantly, or all those who remain unvaccinated inevitably get infected by the delta variant.
“It’s so transmissible. That’s indisputable,” said Dr. Monica Gandhi, an infectious disease specialist with UCSF. “Delta is going to find everyone and cause immunity, but through terrible ways. And it’s going to take much longer than giving people vaccines.”
More than 55% of Californians are fully vaccinated. The Bay Area’s rates are higher, with most counties at least 65% fully vaccinated.
But elsewhere in California, the challenges are immense.
“Our hospitals are all full,” said Dr. Stuart Cohen, an infectious disease specialist at UC Davis. “We don’t have quite as many patients as we had in the wintertime, but we are starting to get close to those numbers. And about 95% of those people are not vaccinated.”
Vaccination levels in Sacramento County remain at only about 52% and hospitals are under enormous strain, Dr. Olivia Kasirye, the county’s health officer, said Thursday. Currently, there are 420 cases of COVID-19 in Sacramento’s hospital; 106 of those are in the intensive care unit.
“We are concerned about the status and the availability of both the general beds as well as beds in the intensive care unit. So we are requesting all members of the public to please, if you do not have a true emergency, to use other means of getting care,” Kasirye said.
Deaths, a lagging indicator of case trends because they tend to occur several weeks after
people are initially infected, have also begun increasing across California, and state models project that nearly 2,000 people will die within the next three weeks, adding to a state death toll that is approaching 65,000.
A UCSF epidemiological model predicted the current surge would peak in mid-August and that the state will be back to low case numbers by mid-to-late September, Gandhi said.
“A lot of the rising cases that we saw over July to early August was driven by the restrictions being lifted in June and people getting together again, taking off masks and relaxing,” Liu said. “It happened to overlap with the time the delta variant started to take off.”
Since protective measures were put back in place, the statewide positivity rate — meaning the proportion of coronavirus tests that come back positive — has dropped 25% in the past three weeks, from a high of 7% of those tested to 5.2%.
“After a year and two-thirds of this mess, we kind of know that it takes a little while for these measures to kick in, but then they start exerting pretty powerful negative pressure on the virus,” Wachter said. “The only good thing about exponential spread is exponential decay is also really fast. Once
cases start going down, there’s less virus around the spread. And as long as people don’t let down their guard too soon, it usually comes down pretty fast.”
Many experts hope vaccination rates increase as more employers mandate the shots and proof of vaccination is required to participate in more activities.
They also expect that some people will be more comfortable with getting the shots after the U.S. Food and Drug Administration on Monday gave full approval to the Pfizer vaccine for people 16 and older — a step up from emergency authorization, which had been in place previously.
“I’m interested to see what happens in the next week or so. Is that going to change anybody’s mind?” Cohen said.
“I don’t know if we’re at a plateau here, but if we are, it’s a little bit higher than any of us want it to be,” he added. “We haven’t started to see the dipping of the numbers, although I would like to be optimistic about it and think it will start happening. Right now, we’re in the middle of it.”