With the omicron variant spreading quickly even among vaccinated people, and pandemic-weary families eager to gather for the holidays, at-home COVID tests are flying off the shelves as fast as stores can stock them. Lines at testing sites across the Bay Area are long, and some places that welcomed walk-ins are now requiring appointments as demand outstrips availability at certain locations.

While health experts say testing is a valuable tool for keeping people safe, all those nasal swabs happening at home this week could actually pose a challenge when it comes to the state’s COVID-19 data and our understanding of exactly where and how the virus is spreading. That’s because the results of the more accurate “PCR” tests done by private and county labs are reflected in California’s COVID-19 data, but the results of rapid tests people take at home are not, which could mean a major undercount.

“It definitely will underrepresent how many people are infected,” said John Swartzberg, clinical professor emeritus at UC Berkeley’s School of Public Health, of the official state data. “We don’t know how large a problem that is.”

While public health officials often ask people who test positive at home to get a PCR test, many people may not take the time to do so, especially if they are asymptomatic or have mild symptoms.

“People know how to deal with it,” said George Rutherford, an infectious disease expert at UC San Francisco. “They’re probably not going to confirm with a PCR test.”

The California Department of Public Health said in a statement: “A positive self-test can stand on its own to diagnose someone with COVID-19,” adding that some home tests provide a way to report results.

In response to a question about whether the state is concerned about an undercount, CDPH said only: “At-home tests will likely increase access to testing, and increase the number of people testing. This could lead to people isolating sooner when infectious with COVID-19 and prevent the spread of the virus.”

Even when people want a lab test, snagging one can be tricky. The current holiday COVID-19 surge is upending plans across the Bay Area as people who would rather be preparing for Christmas were either running from store to store searching in vain for the rapid home test kits this week or waiting in line at testing sites, sometimes for hours.

“I’m desperate,” said Caleb Sanders, 27, a musician who was exposed to the virus last weekend and showed up at the OnPoint testing site on O’Connor Drive in San Jose on Thursday. “I’ve been to at least five CVSes or RiteAids and Walgreens to try to get an at-home test. I tried to call this place but was on hold for 10 minutes and decided to just show up.”

Dozens of people in their cars had already signed up online for appointments and still waited up to four hours to get to the front.

SAN JOSE, CALIFORNIA – DECEMBER 23: Katy Bartlett, of San Jose, Elizabeth Bartlett, of San Jose, and Patrick Bartlett, of San Jose, stand in line for COVID-19 testing before the Christmas holiday in San Jose, Calif., on Thursday, Dec. 23, 2021. (Shae Hammond/Bay Area News Group) 

With just one day before Christmas Eve, the Bartlett family of San Jose considered canceling dinner for 28 guests when they couldn’t find any at-home tests.

“We have one test at home but needed three more — they were nowhere to be found,” said Katy Bartlett, relieved to get an appointment with her two children at the OnPoint testing site Thursday.

She is feeling optimistic everyone will test negative. They already set up five tables in the living and dining rooms and peeled the shrimp for the traditional cioppino feast.

Finding a test was so difficult for Brandon Fitzgerald that he came to Oakland International Airport on Thursday looking to land a rapid test even though he was not flying.

“There’s not many people administering them,” said Fitzgerald, who had a close contact test positive for the virus.

Reservation portals for testing at all three Bay Area airports are booked through Christmas, but travelers can typically arrive early for walk-in appointments.

Curative and Carbon Health, companies that have COVID testing sites across the Bay Area, are both seeing increased demand.

From December 16-22, Curative did 3,579 tests at the Berkeley Adult School, compared to 1,755 tests the previous week. Last Tuesday, Curative administered 181 tests at Mitchell Park Community Center in Palo Alto. This Tuesday, the number rose to 414, said company spokesperson Pasquale Gianni.

“Since Thanksgiving, we have seen a doubling in test volume in our Carbon Health Bay Area clinics and a doubling of the positivity rate of tests, suggesting that there are now about 4x as many positive patients we are identifying just since Thanksgiving,” Carbon Health co-founder Caesar Djavaherian said in a statement.

Health care providers such as Kaiser and John Muir Health have also seen more demand for testing. So have many counties, including Santa Clara, which unlike some other jurisdictions, says that people who test positive at home “generally do not need” to follow up with a PCR test.

“With the rise in use of at-home tests, we expect that COVID cases will be undercounted, but this is something we have been anticipating,” the county said in a statement. “That’s why we also look at other measures like wastewater data, emergency room visits, and hospitalizations to get a sense of what the virus is doing in our county.”

There are some efforts to capture at-home test results, though. Marin County has an online form where residents can report their results, which lets the county follow up with people who test positive to encourage them to isolate and get a PCR test.

Marin County Public Health Officer Matt Willis sees rapid home tests as a critical strategy for helping families navigate the pandemic but acknowledged in a phone interview Thursday that “the more home tests are used, the less precise our understanding is of where the virus is flowing and how many cases we have.”

The online form, which he said has seen an uptick in traffic this week, “helps us see more than we would see otherwise.”

“We just need to rethink our relationship with testing completely,” Willis said. “The tests are an excellent stocking stuffer this year.”

Source: www.mercurynews.com