The U.S. Food and Drug Administration (FDA) said it is 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. The agency is doing so because 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’s genome assessed by that test, the agency said.
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, which has been associated with an increased risk of infection. However, the FDA believes the risk that these mutations will impact overall testing accuracy is low.
“The FDA will continue to monitor SARS-CoV-2 genetic viral variants to ensure authorized tests continue to provide accurate results for patients,” said FDA Commissioner Stephen M. Hahn, MD. “While these efforts continue, we are working with authorized test developers and reviewing incoming data to ensure that healthcare providers and clinical staff can quickly and accurately diagnose patients infected with SARS-CoV-2, including those with emerging genetic variants
Speaking about the impact of variants on vaccines, Hahn said, “At this time, we believe the data suggests that the currently authorized COVID-19 vaccines may still be effective against this strain. The FDA will continue to keep healthcare providers and the public informed of any new information as it becomes available.”
The presence of SARS-CoV-2 genetic variants in a patient sample can potentially change the performance of a SARS-CoV-2 test. Tests that rely on the detection of multiple regions of the genome may be less impacted by genetic variation in the SARS-CoV-2 genome than tests that rely on detection of only a single region.
The FDA said there are three currently authorized molecular tests – MesaBiotech Accula, TaqPath COVID-19 Combo Kit, and Linea COVID-19 Assay Kit – that may be impacted by genetic variants of SARS-CoV-2, but the impact does not appear to be significant. “Importantly, the detection pattern that appears with the TaqPath and Linea diagnostic tests when certain genetic variants are present may help with early identification of new variants in patients to reduce further spread of infection,” the FDA said.
