Though experts say there is now evidence that the presence of antibodies results in some immunity to the virus that causes Covid-19, there are still many unknowns, such as what level of antibodies is needed for protection and how long any immunity lasts.
For a closer look at all of these issues, we asked experts what we know—and don’t know—about the tests.
If I have antibodies to the virus that causes Covid-19, does that mean I’m protected from getting it again? If so, for how long?
Experts say recent studies have concluded that antibodies provide some level of protection or immunity from getting the virus again. What remains unknown is how long that protection lasts and what level of antibodies is needed for immunity.
Where can I get an antibody test?
The FDA has approved about 15 tests and the numbers are growing. None of the approved tests can be conducted in a physician’s office, but doctors can send blood samples to labs to process the test results.
How reliable are antibody tests?
The quality of antibody tests improved a lot after the FDA tightened regulations in early May, says Dr. [Amy] Karger. Manufacturers that couldn’t provide validation for their products within 10 days had to withdraw from the marketplace. “This removed some of the questionable products and built trust in terms of accuracy,” says Dr. Karger.