Alarming decline in COVID-19 testing in Sonoma County could hinder reopening more businesses

A dramatic decline in the number of Sonoma County residents getting tested for the coronavirus could impede recent progress in the monthslong battle to reduce spread of the deadly virus and delay reopening more businesses.

Also, the alarming drop in testing in the community makes it more difficult to find variants of the pandemic disease emerging in other parts of California, the nation and abroad, local public health officials and medical experts said.

Since the end of December, the volume of COVID-19 tests countywide has fallen by about 28%, from roughly 3,400 daily to about 2,400 tests a day.

During that stretch, the number of tests conducted has declined at the county public health laboratory, local hospitals and community health clinics.

Throughout the ongoing pandemic that began last March, health officials have declared many times that testing residents for the coronavirus is instrumental to gaining control of transmission of the infectious disease. More testing is needed, not less, they have said.

Although the public’s attention since December has shifted toward getting vaccinated against the virus, this week elected and health officials made their biggest push in months to urge people to get tested for the highly contagious disease, even as new virus cases in the county decline. Viral transmission levels are now down to where they were in October, before the start of the winter surge that led to local records of monthly COVID-19 infections and deaths in January.

“Testing has been a key component of our COVID-19 response from the early days of the pandemic, and it remains just as important today,” Dr. Sundari Mase, the county’s health officer, said Thursday. “I am concerned that with the arrival of vaccines in the county, people will lose focus on the mitigation measures, including testing, which we know work in stopping the spread of the virus.”

Mase and other county officials issued a clarion call for more testing reminiscent of their message last fall, following the pandemic’s deadly summer surge. At that time, the county’s public testing had reached its broadest availability. New daily virus infections were stable, yet the county remained where it still resides, in the most restrictive tier of the state’s four-part reopening plan because the coronavirus continued to spread widely.

The county now sits on the precipice of finally being eligible to advance to a less restrictive reopening stage, Mase said. Boosting testing volume could improve the county’s chances of attaining the state’s required COVID-19 benchmarks to allow the resumption of more commerce and public activities.

However, officials are concerned the fixation on vaccinations may very well be distracting people from the importance of residents getting tested when they have symptoms, or may have been exposed to the virus that’s killed almost 300 in the county. With close to 20% of the local population having received at least one of the two inoculations needed against the virus, some people might be enjoying a false sense of security, not adhering to public health practices of mask wearing and social distancing, officials said.

“The vaccine does not ensure that you don’t get COVID-19,” Mase said, noting studies show people can contract the virus even after being vaccinated, “and you can transmit it to other people.”

Dr. Urmila Shende, leader of the county’s vaccination campaign, said people concerned about possible exposure to the coronavirus should be tested even after being vaccinated, especially after only receiving a first shot.

“We know that full immunity is not reached until two weeks after dose number two,” Shende said.

Testing decline statewide

The decrease in COVID-19 testing volume is not unique to Sonoma County. California public health officials reported similar declines across the state.

As of last Friday, statewide weekly testing volume decreased 32% in January, from 2.2 million in the week beginning Jan. 3, to 1.5 million tests in the week starting Jan. 31, according to state data. Over that same period, state officials reported 73% the state’s 58 counties saw testing volume declines that were equal to or greater than 15%.

The week ending Feb. 6 was the third consecutive week in which the number of coronavirus tests statewide had decreased. State officials say these declines are consistent with the downward national testing trend.

State public health officials said it will take many months before enough people are fully immunized against the virus to stop its spread. Therefore, they do not recommend deviating from the state’s COVID-19 testing guidelines, even for those who have been vaccinated.

Before Christmas In Sonoma County, as many as 680 per 100,000 residents were getting tested each day. That’s about 3,400 daily tests countywide. Testing volume dipped during the holiday season, before again increasing during the first week of January. County officials this week reported the daily testing rate had dropped to about 490 tests, only slightly above the state’s median testing rate of 425 daily tests per 100,000 residents.

As part of the statewide pandemic reopening process, counties receive an adjustment based on local testing volume relative to the state median testing rate. If the local testing rate is greater than the state median, the county’s daily virus case rate — a key measure of COVID-19 transmission — is adjusted downward to account for the greater number of new infections being found.

The state assesses all counties’ virus transmission benchmarks every Tuesday.

Last week, Sonoma County’s testing volume dipped below the state median, so the county’s daily case rate was adjusted upward from 20.8 to 21.2 per 100,000 residents. This week, with a testing rate barely surpassing the state median, the county’s daily case rate was adjusted from 15.3 to 13.8 daily cases per 100,000 people.

The county needs to push that case, or daily rate of new virus infections, down to 7 or less per 100,000 residents, in order to qualify to advance under the state’s reopening plan and lift more limits on most businesses. For example, the county’s restaurant sector remains restricted to outdoor dining and takeout. During the recent winter surge, only takeout service was permitted.

“Testing can help detect COVID cases early, and stop possible outbreaks,” Mase said. “And it also will help us reopen our economy.”

Identifying virus mutations

As new coronavirus variants, both foreign and homegrown, begin to emerge, public health experts underscore the importance of testing to spot them.

Dr. John Swartzberg, a UC Berkeley infectious disease expert, said that without adequate testing done, it’s difficult to track the trajectory of the virus. But also, he said, insufficient testing cripples public health officials’ ability to judge the role coronavirus variants are playing, and will be playing, in the pandemic.

“Without testing, we’re blind,” Swartzberg said.

D’Arcy Richardson, Sonoma County’s director of nursing for COVID-19 response, agreed. Testing is essential for tracking COVID-19 mutations, she said, some of which could make the virus more transmissible.

“If we don’t have people getting tested, then we can’t do that genotyping to look for those new strains from South Africa, from the UK, from Brazil,” Richardson said. “It’s really important for us to know what’s happening to be able to mitigate and stop that transmission as quickly as possible when we start to see those strains ... that could make these wonderful vaccination efforts less effective.”

Fewer tests at hospitals

County public health data show significant declines in testing conducted at the local public health lab, the county’s three large hospitals and at state-contracted OptumServe public testing sites.

For example, Kaiser Permanente went from doing more than 5,420 coronavirus tests during first full week of January, to 2,871 during the first week of February. Public health lab testing plunged from a high of nearly 5,000 tests during the week starting Dec. 6, 2020, to 2,820 in the first week of February.

Locally, OptumServe, which reached a high of nearly 5,000 tests during the first week of January, has dropped to 2,650 tests during the first week of this month. Also, testing at local health clinics has declined somewhat during that period, according to county public health data.

Providence St. Joseph Health, which runs Santa Rosa Memorial, Petaluma Valley and Healdsburg hospitals, went from 1,128 weekly virus tests to 819, during that same monthly stretch.

Dr. Chad Krilich, Providence St. Joseph Health’s chief medical officer, said the COVID-19 tests included those administered in emergency rooms, urgent care centers or in the hospitals. The declines, he said, could be caused by an actual decrease in coronavirus transmission, or possibly people’s lack of interest to be tested.

“Ultimately, my concern is that we don’t forget what it is that we need to do in order to see us through this phase of the pandemic,” Krilich said, citing virus tests as a critical item.

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