The Food and Drug Administration (FDA) has approved the first test in the U.S. designed to detect coronavirus antibodies, according to a letter of authorization. Widespread antibody testing can be useful in determining how many people in a population were infected with the virus and might now be immune.
Up until now, all of the coronavirus tests conducted in the U.S. were designed to find fragments of the virus itself. This type of test, which uses a method called PCR to find viral RNA in nasal samples, is useful for detecting people who are currently infected with the coronavirus.
But diagnostic tests won’t be useful in identifying people who have already recovered from COVID-19, as they will no longer have detectable levels of viral RNA in their body. These recovered patients will, however, have antibodies that fight off the virus circulating in their blood.
The FDA approved this test, produced by the biotech company Cellex, under “emergency use authorization,” which allows for the tests to be used prior to gaining full approval, provided there aren’t any already-approved alternatives, according to the FDA.
