UK variant of coronavirus identified in Sonoma County

Public health officials reported Tuesday the U.K. variant of the coronavirus, a more contagious strain of the infectious disease, has been detected in Sonoma County.

The California Department of Public Health notified county officials Monday the mutation was present in a local COVID-19 test sample.

The variant was discovered after a county resident went to an unidentified local pharmacy to be tested for the pathogen, said Dr. Kismet Baldwin, the county’s deputy health officer.

Public health investigators soon should have more information about the person the variant strain was connected to, including the person’s recent travel history and potential exposure to others, Baldwin said.

On the same day health officials confirmed presence of the United Kingdom variant in the community, they also reported Sonoma County has made strong recent progress in curtailing viral transmission. It wasn’t enough, though, for the state this week to finally ease strict limits on business and public life in place locally since late August.

The highly contagious U.K. variant was not detected through state and federal surveillance programs, in which the county has been participating since January.

It was a mystery Tuesday why the particular person’s virus test sample was sent for genetic analysis to an outside laboratory where the U.K. strain was discovered and then reported to state health officials, Baldwin said.

“We’re still trying to really piece this story together to find out if there’s anything more,” she said, noting county officials were told the infected resident and a roommate both were apparently in isolation and not in contact with others after testing positive for the coronavirus.

Local public health staff members have not talked to the infected resident since learning Monday of the U.K. variant confirmation. Baldwin notified the county Board of Supervisors Tuesday, during a pandemic update.

“I don’t think it would be unlikely that there’s more cases (of the variant). But we don’t know, and we’re investigating that case as we speak,” she told supervisors.

Dr. John Swartzberg, a UC Berkeley infectious disease expert, said the three coronavirus vaccines the federal government has approved each gives a “very robust” immune response for people against the U.K. strain.

“This is one reason why we need to immunize as many people as quickly as possible,” Swartzberg said.

For weeks, Sonoma County health officials have expected that COVID-19 variants eventually would be found locally since the coronavirus is constantly mutating, a natural course for viruses. The state and federal surveillance programs the county is part of are aimed at identifying variants to slow their spread. Both efforts are in their infancy.

After almost a year of fighting the ongoing pandemic disease, there’s now a race to vaccinate as many county residents as possible before a more dangerous COVID-19 variant, such as the U.K. one, becomes the dominant strain. This all-out effort is being replicated in other parts of California, and in many areas of the country and world.

Baldwin said the U.K. variant does spread easier and there is a potential that it could circulate quickly in the county and across the state.

“It's unknown right now, at least for California, if it's going to contribute significantly to another surge or an increase in the number of cases. We don't know yet,” she said. “We're watching it, and the state is watching it.”

Swartzberg said the latest scientific data suggested the U.K. variant is between 40% and 45% more transmissible than the early strain of COVID-19. Some data indicated that it may cause more severe illness, he said, but such claims are still speculation.

This variant has probably been in the United State since September or October, but did not become prominent until early January, experts said.

“Right now, it is doubling every nine to 10 days,” Swartzberg said of the U.K. strain. “It will likely become the dominant strain by the end of this month.”

The variant, B.1.1.7, which first emerged last fall in the United Kingdom, had been detected in Southern California.

A South Africa variant, B. 1.351, shares some characteristics with the U.K. variant and is also thought to be more contagious than the current dominate strain.

And a homegrown variant, known as the California variant, B. 1429, has been detected in Marin and Lake counties but not in Sonoma.

County health officials have been submitting a small number of residents’ COVID-19 specimens to the Centers for Disease Control and Prevention for analysis to detect coronavirus variants. Baldwin said the county has thus far not received any confirmation of variants found in any local samples sent to the CDC.

Meanwhile, during the supervisors’ meeting Tuesday, public health officials said the county continues to show improvement in the key COVID-19 transmission benchmark the state uses weekly in its criteria for continued reopening of business and public life in California’s 58 counties.

However, Sonoma County’s latest virus transmission level — 10 new daily cases per 100,000 people, down from 14 infections a day — is still too widespread for the county to advance from the most restrictive purple stage in the state’s four-part reopening plan. For the county to advance from where it’s been stuck into a seventh month with tight restrictions, including only outdoor restaurant dining and gym workouts outside, that daily case number needs to fall to 7 or fewer.

In other parts of the Bay Area, San Francisco, Santa Clara and Napa counties will join four other counties Wednesday in moving out from under California’s most restrictive rules in the purple tier. That means, among other things, in those locales indoor dining at restaurants, breweries and wineries, plus movie theaters, can reopen at 25% capacity or up to 100 people. And gyms and yoga studios can resume workouts inside at 10% capacity. Museums, zoos and aquariums also can open indoors at 25% capacity.

Sonoma County public health officials repeated Tuesday that the volume of residents getting tested for the coronavirus continues to be far below levels here during the winter surge, notably more than 1,000 fewer tests a day since December and January.

Health officials said much more COVID-19 testing is needed to quickly identify fresh infections and to finally loosen more business limits. The state awards a favorable adjustment to counties when their test volume exceeds the statewide median.

County officials said they plan to launch an aggressive public health communication campaign early next week through local media urging residents to get tested for the virus and vaccinated against it, as well as to continue to wear masks and practice prudent social distancing and personal hygiene.

Baldwin, the county’s deputy health officer, said the U.K. variant’s detection came as virus cases continue to decline throughout the county and state. But she stressed the need for area residents to remain vigilant and to continue adhering to pandemic safety measures, including limiting gatherings with people outside households.

The more the coronavirus spreads, the more its variants will transmit in the county, she said.

“We want to limit the spread of the variants as much as possible, but they are in the state and we don’t want to see another increase in cases again,” Baldwin said.

You can reach Staff Writer Martin Espinoza at 707-521-5213 or martin.espinoza@pressdemocrat.com. On Twitter @pressreno.