There’s a lot more COVID-19 in Sonoma County than data shows

Don't be fooled by Sonoma County’s low COVID-19 case rates this winter — in fact, don’t even try to compare today’s pandemic stats to last year’s.

If you look at the county’s latest COVID-19 data, by the end of December roughly 60 people in Sonoma County were getting infected every day with SARS-CoV-2, the virus that causes the COVID-19 illness. A year earlier, in late December 2021, there were roughly 500 daily infections.

But that’s comparing apples to pumpkins — really big ones.

On Dec. 30 — the most recent data available — there were 676 official COVID tests conducted in Sonoma County. On that date a year earlier, as omicron infections surged, there had been 6,210 COVID-19 tests administered.

More tests yield more infections, which means there’s likely a lot more COVID-19 in the county than our data is telling us. The good news is that rates compared to just two months ago are tapering off and severe COVID-19 illness is not as bad as it was last year.

“There's an awful lot of COVID out there and the chances of you getting infected are very high right now,” said Dr. John Swartzberg, a UC Berkeley infectious disease expert. “But this is nothing like last year and nothing like the year before in terms of the really serious impact that this virus was having on our population.”

Swartzberg said the current data is useful only when comparing trends over the past few weeks. He said the current transmission rate, about 12 new daily cases per 100,000 residents, is twice what it was in early November.

Swartzberg said the rise of infection rates in late November and into December were “concerning.” But in the final weeks of December, case rates began to flatten out and even come down a bit.

“We can thoroughly say that this year is nothing like last year,” he said. “But in terms of how many people are actually getting COVID and spreading it. I think the numbers are really really quite high.”

Kathryn Pack, health program manager for the county's epidemiology team, confirmed that the current COVID-19 transmission rates likely undercount the number of actual infections due to low testing volumes.

She added that one sign of the undercount is the high test positivity, the share of COVID-19 tests that result positive. Test positivity on Dec. 30 was 11.9%, compared to 15.1% a year earlier.

“Elevated test positivity suggests that there is more COVID-19 present in the community than is currently being detected through PCR testing,” Pack said.

Health officials have repeatedly pointed out that many local residents today are less likely to use PCR tests and opting instead for rapid home tests. In many cases, officials said, positive results from rapid tests are not being reported.

Swartzberg said that for now, COVID-19 hospitalization and death rates this winter are much lower than they were last year. That could change with the rise of a more virulent strain that leads to more severe illness than current offshoots of the omicron variant.

“We're not seeing anything like the hospitalization rates of last year at this time,” he said. “And we're not seeing anything like the death rates of last year at this time. So from that perspective, I think this is clearly a better year. We're not seeing as many Americans dying.”

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