CDC: Coronavirus antibodies could give "short-term immunity," but more data is needed

Coronavirus antibody tests are still relatively unreliable, and it's unclear if people who get the virus are immune to getting it again, the Centers for Disease Control and Prevention cautioned on Tuesday.

What they're saying: The agency explicitly warned against using antibody tests to determine whether someone should return to work or to group people within schools or prisons.

• Although some evidence suggests that previously having the coronavirus could create "short-term immunity," it is still ultimately unknown whether having COVID-19 antibodies offers protection from the virus, the agency said.
• Social distancing and face masks are still essential and should not be avoided based on whether you have coronavirus antibodies. More data would be needed for those changes, the agency says.

Between the lines, via Axios' Caitlin Owens: The CDC's updated guidelines point out that even effective antibody tests are likely to have high false positive rates, since not many people have tested positive for the coronavirus.

The big picture: The CDC's caution comes after it confirmed last week that it had been combining the results of diagnostic and antibody coronavirus tests. This distorts data on how widespread the virus is, which is one of the primary uses of antibody tests.

• It also follows a warning from the American Medical Association that antibody tests that identify those who have previously contracted the coronavirus should not be used to determine immunity.

Go deeper: FDA blocks sale of 29 coronavirus antibody tests in the U.S.