The U.S. Food and Drug Administration (FDA) said that results from currently authorized SARS-CoV-2 antibody tests should not be used to evaluate a person’s level of immunity or protection from COVID-19 at any time, and especially after the person received a COVID-19 vaccination.
“While a positive antibody test result can be used to help identify people who may have had a prior SARS-CoV-2 infection, more research is needed in people who have received a COVID-19 vaccination. “
Authorized SARS-CoV-2 antibody tests have not been validated to evaluate specific immunity or protection from SARS-CoV-2 infection, the FDA said, adding that this applies to qualitative, semi-quantitative, and quantitative SARS-CoV-2 antibody tests.
The FDA also noted that vaccines trigger antibodies to specific viral protein targets, and people vaccinated against COVID-19 will only receive a positive antibody test if the assay detects the specific antibodies induced by the vaccine.