Bay Area hopeful as virus rates fall

After summer surge, cases declining in most counties

After a deadly summer surge during which hundreds of Bay Area residents died from COVID19, some parts of the Bay Area are finally seeing a slowdown in the spread of the coronavirus.

New coronavirus cases are stabilizing or declining in eight of the nine Bay Area counties, according to cases reported by county health departments and compiled by The Chronicle.

The Bay Area as a whole saw a 4.8% decline in new cases for the week that ended Aug. 23, compared with the week that ended July 26, according to Chronicle data.

During those periods, the nine Bay Area counties reported 1,000 new cases per day in midAugust, down from 1,050 cases per day in midJuly. Those periods were mostly unaffected by the computer glitch that caused delays in reporting at the state level, though the July figures may be slightly underreported.

The trend is similar to statewide and national slowdowns in new infections. New cases in California are down 34%, dropping from an average of nearly 9,400 cases a day during the week that ended July 26, to fewer than 6,200 the week that ended Aug. 23. Hospitalizations are also down

40%, declining from the July 21 peak of about 7,200, to 4,200, state officials said Friday. COVID19 deaths appear to be stabilizing, hovering from 120 to 130 per day, on average, for the past two weeks.

The slowdown sets the stage for the state and region to attempt a second, slower economic reopening plan, which Gov. Newsom announced Friday. The hope is that cases can remain on a downward trend while businesses, schools and other societal functions can resume to some degree of normality.

Nationally, cases also declined 35%, from nearly 66,000 cases a day to fewer than 43,000 during those same periods. Still, the U.S. outbreak remains one of the worst in the world, behind just India and Brazil in new daily cases, according to data from Johns Hopkins University School of Medicine.

“We really are in the downslope of this second wave of the epidemic here in the U.S.,” Dr. George Rutherford, head of UCSF’s division of infectious disease and epidemiology, said during a briefing with reporters Wednesday. “It looks like we’re on the downslope (in California) as well.”

The main factors driving the statewide and regional slowdown are that people are wearing masks, social distancing and socializing less — and more carefully — with friends and family, experts said.

“The reason it’s going down is people are wearing masks and social distancing, period,” Rutherford said. “It has nothing to do with herd immunity. People are doing the things it takes to not get infected.”

“We have flattened the curve,” Marin County Public Health Officer Dr. Matt Willis said Tuesday during a COVID19 update to the Board of Supervisors. “The second large wave has flattened in July and is now on its way down. That seems to be a reliable pattern of improvement.”

Marin, like the Bay Area as a whole, initially flattened the curve in the spring, only to see a larger, second surge of cases begin in May, after reopenings began. Marin was averaging 163 cases a day in the week leading up to July 3, and that has since tapered off to 27 a day in the week leading up to Aug. 28, according to Chronicle data. Much of the summer surge was linked to outbreaks that began in June at San Quentin State Prison, which reported about 2,000 cases. The prison has reported almost no new cases in the past few weeks, which accounts for much of the decline. New cases in the community, separate from San Quentin, also rose during the same period and are now falling as well.

In Solano County, new daily cases peaked at 101 in midJuly and have since declined relatively steadily, reaching 31 on Aug. 27 — the lowest sevenday average since midJune, according to county data.

While people are still socializing — gatherings with friends and family are a major source of transmission — it seems that fewer people are doing it, which is helping reduce infection rates, said Dr. Bela Matyas, health officer for Solano County. The recent heat wave and poor air quality from the wildfires may also have driven people to stay home more, he said.

“It could be people are listening to the messaging and trying to interact with one another in safer ways,” he said. “It’s hard to know because we’re not in people’s homes to see what they’re doing.”

Some local health officers noted this month that cases in their counties appeared to begin stabilizing or declining in July. But because the glitch in the state’s data reporting system, CalREDIE, happened around the same time, it took some time to determine whether cases were in fact declining or whether the apparent decline was because of underreporting. A technical problem with CalREDIE, caused by a server malfunction on July 25, led to many cases being temporarily underreported. State officials say the issue has been resolved.

“At first we weren’t sure if it was real because of the state data problems, but those have been resolved satisfactorily so we can trust the numbers,” Matyas said.

In San Francisco, new cases peaked July 20, when the city reported a sevenday average of 130 cases per day; that has since declined to 72 cases a day as of Aug. 22, the most recent day for which there is reliable data, according to county data. The data reflect the previously underreported cases from CalREDIE, though the city is continuing to verify the figures.

“That number has been coming down in the recent weeks, but it remains in the red zone,” San Francisco Health Director Dr. Grant Colfax said Friday.

It is too early to tell whether San Francisco is indeed flattening the curve, and the city will “remain vigilant,” according to a statement from the San Francisco COVID Command Center.

Cases in San Mateo, Contra Costa and Alameda counties have also been stabilizing or declining over the last few weeks.

But Sonoma County is not seeing a slowdown. And the recent wildfires forced thousands of Northern California residents to evacuate and congregate in shelters and homes where households mix — raising concerns that such environments may lead to more virus transmission.

“I wouldn’t say we have a slowdown in cases,” Dr. Sundari Mase, health officer for Sonoma County, said Wednesday.

She noted that the “R naught,” one measure of how fast the virus is spreading, is decreasing, which could signal movement in the right direction.

“But we had fire and evacuations, people mingling, whether it be in shelters, family and extended family and friends’ homes,” she said. “We’ll have to see . ... I don’t think we can say things are slowing down at this time.”

Given that the Bay Area flattened the curve in the spring — only to reopen quickly and see a surge in new cases — businesses and residents will have to move more slowly and cautiously to reopen this time around, infectious disease experts say.

San Francisco is poised to begin allowing some outdoor personal services Tuesday, including nail and hair salons and outdoor gyms, Mayor London Breed announced Friday while acknowledging that reopening may lead to more spread.

“As more things open in San Francisco, the possibility for spread goes up, so the last thing we want to do is to go backwards,” she said.

Starting Monday, California will embark on a new reopening plan in which counties are grouped into one of four tiers based on how well they are controlling the virus. The tiers are colorcoded: the most severe and restrictive, purple, signifies the highest case rates and test positivity rates. The least restrictive, yellow, allows counties to be nearly fully reopen. The vast majority of the state, including seven of the nine Bay Area counties, is in the purple tier. Counties must sustain case rates and test positivity rates for at least three weeks before progressing to the next tier.

UCSF’s Rutherford is especially concerned about schools. Outbreaks have already been reported at the University of North Carolina, Notre Dame and dozens of other colleges and universities.

“We’re going to have to go slow,” he said. “The colleges, high schools and middle schools need to really be advocates for masks . ... It’s not going to be college as usual, high school as usual, life as usual for quite a while. But if we want be able to keep case counts down, we want to not crush the intensive care systems that we’ve developed, we’re going to have to wrap our heads around wearing masks and not being able to do whatever we want to, whenever we want to.”

Catherine Ho is a San Francisco Chronicle staff writer. Email: cho @sfchronicle.com Twitter: @Cat_Ho