Coronavirus: Why your COVID-19 test results are so delayed

Within two to three days, you can get results from your cholesterol test or colonoscopy. But the speed at which the dangerously infectious COVID-19 virus is detected varies greatly — from an hour to two weeks or more.

As cases climb and supplies plummet, the pandemic is revealing a gulf in the Bay Area testing’s landscape: selective academic labs that are technically and logistically agile, returning results quickly, and facilities that rely on commercial labs with rigid supply chain requirements that can cause results to be significantly delayed.

The waiting game is stressful for anyone who relies on a test to resume their lives and livelihoods.

“It was frustrating for those two weeks not knowing,” said Jackie Erickson, of Los Gatos, who was tested at a CVS drive-thru site in San Jose before taking her sick and elderly mother to an important doctor’s appointment. She helped her mother before her results were returned — all the while, fearful of infection.

What’s happening? All over the world, labs are scrambling to find supplies at nearly every link of the supply chain, from the chemical reagents and plasticware to the actual machines that process tests. Four companies — Cepheid, Hologic, Abbott and Roche — dominate this machine market and require brand-name components.

“There are supply chain shortages for essentially everything,” said Dr. Steve Miller, director of UCSF’s Clinical Microbiology Laboratory. Manufacturers ration what’s sent to each lab, he said.

“Every institution is left to fend for themselves,” he said. “It’s like a competition. We’re all after the same supplies.”

The most profound shortage right now is tiny plastic pipette tips, which are critical for dispensing liquids onto a small plate to search for viral DNA.

“The companies that manufacture testing machines, supplies and equipment are struggling to meet the growing global demand, and currently they are not able to keep up,” said Dr. Stephen Parodi, infectious disease specialist and clinical lead for Kaiser Permanente’s coronavirus response.

Across the nation, turnaround times for test results have doubled in the last few weeks, he said.

Some of the worst waits for results are at labs at public retail outlets such as CVS. Such places send the tests in bulk to centralized labs owned by just a few commercial processors such as Quest Diagnostics and LabCorp. These processors use just one or two types of instruments, so they’re locked in to using proprietary chemical kits and other tools. They run tests in batches and may be located far away.

As a result, these sites have backlogs — even as they continue to accept new business from the surge of healthy asymptomatic people.

County labs are also typically dependent on public or commercial labs with limited flexibility. For instance, Santa Clara County’s Department of Public Health now takes nine days to return results.

Kaiser, which serves millions of members, is building a new 7,700-square-foot lab in Berkeley to process thousands of COVID-19 tests each day. Parodi said that most tests are processed at Kaiser’s existing lab, and results are ready in two or three days. Less urgent cases, which can be sent to other labs, can take longer, he said.

Currently, some members say it can take nearly two weeks to get results, posing risk of transmission even though they may not have symptoms.

While waiting 12 days for results from Kaiser Richmond, Laura Paull worried about the isolation of her 92-year-old father “sitting alone in his apartment, day after day, with a book open on his lap. When I was finally able to visit, his energy level perked right up.”

But at academic medical centers such as Stanford and UCSF, responses can be lightning fast.

They have several advantages. Their tests are done on campus and, if needed, can be processed immediately. And they can limit who they accept, focusing on people with the greatest need. Only when supplies are adequate do they extend their reach. Stanford helps Valley Care, El Camino, Sequoia and Seton hospitals. UCSF partners with Marin General and John Muir hospitals, as well as some public clinics and county health departments overwhelmed by sudden outbreaks.

Dr. Paul Bayard turned to UCSF after he got weary of waiting up to two weeks for a commercial lab to report results for his patients at the East Bay-based clinic network called La Clínica. Now, with results within one to two days, La Clínica offers quick drive-through testing.

These academic labs have the money to buy many types of instruments, so they’re not at the mercy of one manufacturer. Additionally, they’ve built relationships with different vendors, so they can take advantage of whatever supplies are available.

Stanford’s lab, which conducts 24-hour specimen processing, has multiple workflows, instruments and supply chains, said Dr. Ben Pinsky, director of the Clinical Virology Laboratory for Stanford Health Care.

“We have tried to diversify, making sure we have alternatives,” he said. “There’s always some sort of redundancy in our suppliers. If we have any issues, we have backups.”

UCSF has seven different methods for COVID-19 testing and plans to add two more, said Miller. It also has backup supply chains. For instance, when UCSF starts to run low on the pipette tips of their Hologis Pathway test system, it looks for alternative suppliers. If it can’t find them, it shifts to a completely different instrument, called the CDC Assay.

But even their model can’t sustain the entire nation, Miller said. New and improved test technologies need to be made available to everyone.

“There’s infinite demand,” said Miller. “It is not going to be solved by our lab expanding capacity.”

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