Gottlieb questions accuracy of antibody tests: ‘I’d repeat it three times’

Former FDA Commissioner Scott Gottlieb on Monday warned about the accuracy of antibody tests that show whether someone has had the coronavirus, saying he would take a test three times to be sure of the results. 

“If you do go out and get an antibody test and you get a positive result meaning you have the antibodies, I would suggest you repeat it, because there’s such a high false positive rate, meaning the tests say you have antibodies when you don’t, that I wouldn’t put any stock in any single result,” Gottlieb said on CNBC. 

“Quite frankly if it was me, I’d repeat it three times, I know they’re expensive, but I wouldn’t put confidence in any one test,” he added. 

Antibody tests determine whether has had the coronavirus in the past by testing for the presence of antibodies in the blood, making them different from tests that determine whether someone is currently infected with the virus. 

Some experts have suggested that antibody tests can help some people return to work if they are shown to have the antibodies and therefore have some level of immunity to the virus. But the problems with the accuracy of the tests complicate that effort. 

The FDA on Monday moved to try to increase its oversight, saying that antibody tests would need to receive emergency authorization from the FDA. That could help put more control over the more than 100 tests on the market. 

Gottlieb said a more fruitful use for resources is not more individual-level tests, but rather for researchers to determine roughly what percentage of a given population has had the virus. 

If someone does obtain multiple positive antibody results, Gottlieb said, “I think you can be reasonably confident that you have a level of immunity.”

“Now how long that lasts we’re unsure,” he added. “It’s probably going to be months, it might be a year or more.”