Moderna says its Covid-19 vaccine is less effective against one coronavirus variant 

Moderna is studying adding booster doses to its vaccine regimen after finding its Covid-19 vaccine was less effective 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. Read the rest…