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Researchers say COVID-19 antibody tests may be providing false sense of security

Posted at 5:49 PM, Apr 30, 2020
and last updated 2020-04-30 18:00:44-04

As we inch closer to our country’s reopening, we’re seeing more and more information coming out, touting antibody tests as key to returning to our lives.

The FDA has already approved several of these tests, and they’re available to everyone, right here in Tampa Bay.

But how do you know if you should get one, and are they really worth your money right now?

Antibody tests tell you whether or not you’ve been exposed to particular pathogens, and have developed some sort of immunity to a virus or disease.

As more private labs come out with their own antibody tests, researchers are sounding a bit of a warning.

“If you’re positive, we don’t know that you’re really immune or not,” said Dr. Thomas Unnasch, Distinguished Professor at USF.

The FDA released a statement regarding antibody tests and immunity:

“There is still a great deal about COVID-19 immunity that we don’t yet fully understand. For example, we don’t yet know that just because someone has developed antibodies, that they are fully protected from reinfection, or how long any immunity lasts. We do expect that data from more widespread serological testing will help us track the spread of the virus nationwide and assess the impact of our public health efforts now, while also informing our COVID-19 response as we continue to move forward. Determining the next steps in our response to COVID-19 is partially dependent on an accurate assessment of our national efforts thus far, and the quality of data for making this decision is dependent on accurate testing products.”

Dr. Unnasch joins researchers across the nation in cautioning people against developing a false sense of security from a test that’s still fairly new.

“Until we have a way of saying the antibodies that we’re actually seeing are the ones that neutralize the virus and kill the virus, therefore you’re really immune, all the antibody tests are telling you is whether you’ve been exposed or not,” said Unnasch.

Unnasch also warns that these tests may provide false positive results.

“The coronavirus that’s circulating around now is related to two of our standard cold viruses, and it’s possible that if a person had a cold recently, over the last year or so, that’s caused by one of these other related viruses, they may have antibodies to that cold virus that cross-react,” said Unnasch.

Unnasch says antibody tests will be important in order to understand just how much of the population has an immunity to the virus, but he says it's the second generation of tests, which he believes will be out in the next few months, that will be more reliable.

“The approach that the governor is taking, slowly allowing people to go back out into the workforce, trying to keep the infections down and develop our herd immunity, in the short term is the way that we’re going to have to go,” said Unnasch.

At least until the FDA approves a vaccine.