Antibodies are proteins in the blood that indicate past infections. If someone is shown to have COVID-19 antibodies, there’s a chance they could be immune to it, but researchers still don't know if that's true.
Tons of antibody tests (also known as serology tests) have hit the market recently, but their accuracy varies widely and many haven’t yet gotten an emergency-use authorization from the U.S. Food and Drug Administration, including the test that is being used by the Sky Lakes Medical Center in Klamath Falls.
That antibody test involves sending blood samples to the Mayo Clinic Laboratories in Minnesota. According to documents on Mayo’s website, it’s using a manufactured test by Epitope Diagnostics — a medical device company based in San Diego.
Epitope is among the four companies being criticized by a U.S. House subcommittee for distributing tests that don’t consistently provide reliable results. A recent study — which was conducted by researchers from the University of California San Francisco and the University of California Berkeley, among others — recently showed that Epitope's test provides more false negatives and more false positives than it claims on its packaging.
The House Oversight subcommittee on economic and consumer policy cited the study in its letter to Epitope on Tuesday.
“The discrepancies in these performance characteristics are deeply troubling,” chairman Rep. Raja Krishnamoorthi, D-Ill., wrote in the letter. “The researchers report a much higher risk of false negatives from this test.”
That means there’s a chance that this serology test could give someone negative results, even when they have COVID-19 antibodies in their blood. More troubling, the subcommittee also said it produces more false positives than it claims, which means a patient could be led to falsely believe that they have a degree of immunity to the coronavirus.
The same House panel on Tuesday wrote a letter to the FDA, saying that it "failed to police" serological tests. It cites research that concludes that the FDA’s lax policies are permitting a flood of fraudulent tests into the market.
So, Why Use An Antibody Test In Klamath Falls?
“Because we could, honestly,” Sky Lakes spokesman Tom Hottman says.
Hottman says administrators at Sky Lakes want to start gathering as much data as they can so they could understand how prevalent the coronavirus is in Klamath Falls and the surrounding rural region that it serves.
“Any information is going to be better than no information at all,” Hottman says. “And so, even if it is potentially flawed, still knowing that is going to help inform our decision-making processes.”
The danger, critics say, is that public health officials could make critical decisions based on flawed information. There's also a chance that some patients will incorrectly test positive for coronavirus antibodies, leading them to make lifestyle or medical decisions that expose them to this highly contagious disease.
Sky Lakes began testing patients on April 27, and has since tested more than 1,000 people.
In a statement released Thursday afternoon, Sky Lakes says its physicians are not recommending anyone who tests positive for antibodies to stop social distancing or to stop wearing face masks.
“While we are not using these as point-of-care testing, we have worked hard to be able to bring these tests into our rural area,” reads its statement. “In our correspondence with the Mayo Lab directly we have been reassured by their confidence in the COVID-19 serological antibody test.”
