New COVID-19 subvariant could bring winter surge in Sonoma County; updated vaccine could help

A new subvariant of the highly infectious COVID-19 strain that triggered a prolonged summer surge has surfaced and has the potential to trigger another wave of infections in late fall and winter, local pandemic experts said Tuesday.

BQ. 1 and BQ. 1.1 — subvariants of the omicron subvariant BA.5 — now comprise a little more than 11% of all genotyped COVID-19 strains in the United States, said Dr. John Swartzberg, an infectious disease expert at UC Berkeley.

“But in New York we’re seeing about 25% of all the (genetic) isolates are caused by these two, so the Northeast has more,” Swartzberg said. “They are progeny of BA. 5, the one that we’ve been dealing with this summer, primarily.”

Swartzberg said the new variants, which were barely detectable in September, appear to be growing quickly and could overtake their ancestral BA.5 if their trajectory continues.

“This could likely contribute to increased problems for the late fall and winter,” he said. “I think it’s highly likely we’re going to see another surge … I think the question we all have is not whether there’s going to be one but what is it going to look like — is it going to be very modest, is it going to be moderate or severe?”

Swartzberg said his best guess would be that it’s unlikely to be a severe surge because so many people have some degree of immunity. However, he said, the virus does have the potential to cause problems.

That’s because so many people have forsaken pandemic-era precautions and many have yet to take advantage of the new, updated COVID-19 vaccine, which was reformulated to offer protection against BA. 5, the so-called omicron subvariant.

Dr. Gary Green, a local infectious disease expert who works for Sutter Health, said the new subvariants do not seem to be resistant to antiretroviral drugs such as Paxlovid and molnupiravir, which inhibit the replication of the COVID-19 virus.

Green also stressed the importance of getting inoculated with the new updated vaccine to help prevent a surge. Green said severity of the winter surge will depend on how many people in a given community get vaccinated with the updated vaccine.

“If you vaccinate against BA. 5, you're also cross-vaccinating against all the other sub variants,” he said. “But I think that people are a little bit vaccine fatigued, and I think people are getting tired of hearing about COVID.”

In Sonoma County, the level of COVID-19 transmission continues to be low, according to the federal Centers for Disease Control and Prevention. The CDC lists Sonoma County’s current case rate as about 8 daily cases per 100,000 residents.

According to the county’s COVID-19 dashboard, as of Oct. 17 (the latest data available) there were 21 people in the hospital who tested positive for COVID-19, though some share of that number were likely hospitalized for some other reason. Four COVID-19 patients were in the ICU as of Oct. 17.

Green said he expects the winter surge will be fueled by a number of respiratory viruses, not just COVID-19.

“I definitely think we're going to see a respiratory virus season,” he said. “And that's not just going to be COVID, it's not just going to be the flu — there's RSV (respiratory syncytial virus) going up, we're seeing a little bit of parainfluenza, adenoviruses are out there. I think this year is gonna be a mixed respiratory viral season. It's not just going to be one virus.”

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