On Jan. 8, 2021, the FDA alerted clinical laboratory staff and health care providers that it was monitoring the potential impact of viral mutations, including an emerging variant from the United Kingdom known as the B.1.1.7 variant, on authorized SARS-CoV-2 molecular tests, and that false negative results can occur with any molecular test for the detection of SARS-CoV-2 if a mutation occurs in the part of the virusﾒs genome assessed by that test.

The SARS-CoV-2 virus can mutate over time, like all viruses, resulting in genetic variation in the population of circulating viral strains, as seen with the B.1.1.7 variant. The FDA was taking additional actions to ensure authorized tests remain accurate by working with test developers and conducting ongoing data analysis to evaluate all currently authorized molecular tests.