April 30, 2020 / ROB STEIN
States clamoring for coronavirus tests in recent weeks have been talking about two different types. First, there’s a PCR test that detects the virus’ genetic material, so can confirm an active infection. And then there’s an antibody test, which looks at the body’s reaction to that infection, so is useful in identifying people who have been infected with the virus in the past.
Now, there’s a third kind of test under development to help fight COVID-19 that homes in on proteins that stud the virus’s outer surface; it, too, detects an active infection. Known as an antigen test, this one could offer a much easier and more widely available alternative for diagnosis than the PCR test, proponents say, though some other scientists remain concerned about the test’s reliability.
“We have to have a breakthrough innovation in testing,” Dr. Deborah Birx of the White House Coronavirus Task Force said recently on Meet the Press in her most recent pitch for antigen tests. “We have to be able to detect antigen rather than constantly trying to detect the actual live virus or the viral particles itself.”
Though there are no authorized coronavirus antigen tests on the market yet, several companies are already working on them, including one that has started seeking a stamp of approval from the Food and Drug Administration.
