Moderna’s vaccine is less potent against one coronavirus variant but still protective, company says

Moderna is studying adding booster doses to its vaccine regimen after finding its Covid-19 vaccine was less potent against a coronavirus variant that was first identified in South Africa, the company said Monday. In lab research that involved testing whether blood from people who had received the vaccine could still fend off different coronavirus variants, scientists found that there was a sixfold reduction in the vaccine’s neutralizing power against the variant, called B.1.351, than against earlier forms of the coronavirus, Moderna reported. There was no loss in neutralization levels against a different variant, called B.1.1.7, that was first identified in the United Kingdom. Both variants are thought to be more transmissible than other forms of the SARS-CoV-2 virus.