JOHANNESBURG—Three new laboratory studies are raising concerns that the immune response triggered by a Covid-19 infection or vaccination may be less effective at protecting against the new strain of the coronavirus that first emerged in South Africa.
The findings come from experiments done in the laboratory and only look at certain elements of a body’s immune response. Still, they reinforce the possibility that vaccine makers and regulators will need to update Covid-19 vaccines as the virus evolves.
A fourth study, conducted by scientists at BioNTech SE and Pfizer Inc. and published by the companies, showed that their vaccine successfully neutralized a variant that was initially detected in the U.K. That study didn’t include the South African strain.
The U.K. variant has already spread to many other countries, including the U.S.
More than a year into the pandemic, the discovery of new variants that appear to have made the virus more contagious is forcing researchers to adapt their understanding of the coronavirus that causes Covid-19. One concern, researchers said, is that the new strains are emerging in countries where a significant percentage of people have already built up an immune response to earlier variants after getting Covid-19.