While current national COVID-19 testing — which involves a technique called reverse transcriptase-polymerase chain reaction (RT-PCR) — remains at a shortage, an SF lab is validating a new antibody test, helping to both expand coronavirus testing availability and identify possible cases of herd immunity.
The coronavirus has proven to be a litmus test for privilege, circumstantial or otherwise. Because of how scarce testing still remains, those who have secure health insurance or the financial means to acquire out-of-network tests through a doctor are usually the first in line to receive them. The rest — in some cases, even people who are symptomatic — find themselves toward the end of that figurative queue. But with the possibility of antibody testing becoming available, in tandem with growing numbers of RT-PCR kits, COVID-19 testing could become much more accessible in the weeks to come.
Increasing focus on #ContactTracing and #antibody testing to support the #Containment phase of #COVIDー19 management. Science and sleuthing meet as our surge in #SanFrancisco is anticipated as early as next week. https://t.co/f4S289FOXW— Julie A Sosa (@Jasosamd) April 11, 2020
The work now underway at an SF lab is promising, so much so that a trial of a new antibody test will go live next week.
"We're excited about it, especially the results that we're getting," said Kara Lynch, a UCSF Associate Professor of laboratory medicine and co-director of the clinical lab at Zuckerberg San Francisco General Hospital, to ABC7 on the exclusive update.
"We basically spent the last month validating the [antibody testing ] method — and if you could see the increase and rise in the antibody response over time — because that has not been well characterized yet for this virus," Lynch adds, remarking she and her team have tested some 500 blood samples from 80 COVID-19-positive patients. Those samples were primarily used to gauge fluctuations in antibody levels of the pathogen; coronavirus antibodies can develop as soon as two days once symptoms emerge and linger long after the initial infection.
"Antibodies can show if someone has had a previous infection and this is important because we are not able to do swabs on every single individual in the population, so it's helpful to know the extent, how widespread the infection is," Lynch adds.
And, starting next week, she and her team will start using the antibody test to canvass SF health care employees for the novel respiratory disease. Because these frontline workers face the pathogen nearly every day, they're among the most vulnerable populations to succumb to COVID-19. However there, too, is a chance that many have contracted the disease, but remain asymptomatic.
Alas, once out of the contagious time frame, those workers are invaluable to help ward-off the pandemic's advancement and can simultaneously bolster herd immunity.
"If a health care worker has the antibodies, then they would be at [a decreased] risk of acquiring the virus, so they could potentially be more on the frontline of fighting this and helping those that are infected acutely," Lynch says to the news outlet's Kate Larsen.
Though the UCSF professor was quick to note that they don't know yet if the presence of COVID-19 antibodies guarantees immunity, they're "hopeful" it does: "We're hopeful [COVID-19 antibodies support immunity] because that is what happens with many viruses."
More Bay Area healthcare systems are expected to start both trial and mainstream antibody testing later this month, with those tests only available via a doctor.
While Lynch says she doesn't believe we're heading toward another reagent shortage — the main reason why testing in March was so impaired — backlogged testing could spur delays in results.