Calum Semple, professor of child health and outbreak medicine at the University of Liverpool, said the South African variant’s apparent resistance to antibodies is causing concerns.
“What’s worrying the scientists is that, in the test tubes, it’s showing less susceptibility to two things—less susceptibility to the plasma of people that have had natural infection, and less susceptibility to the plasma from people that have had the vaccine,” he told BBC Radio 4’s “Today” programme.
But he said there is still a lot of uncertainty, because “we haven’t tested against the other parts of immune system—the T cells, and we aren’t seeing yet lots of people coming back into hospital with reinfection, with severe disease, who have previously had the old strain.”
Semple said, “We really just don’t know about the clinical importance of this.”
“The huge effort to test and trace and observe for reinfections and readmissions is incredibly important to help us understand what’s going on here,” he said.
Nick Loman, professor of microbial genomics and bioinformatics at the University of Birmingham, also said the variant’s ability to resist antibodies is “concerning.”
“There is quite good evidence experimentally that a particular mutation in this variant called E484K will help resist antibodies that are generated during natural infection. So, we might expect that this variant could cause more in the way of reinfection,” he told the BBC.
But its potential impact on the effectiveness of vaccines is “a little bit more complicated,” he said.
“There has been a study demonstrating the Novavax vaccine, which isn’t yet used in the UK, did work much less well against this South African variant—B1351—than the other variants including our UK variant.
“But another study recently reports there wasn’t much impact on the antibodies generated by the Pfizer vaccine that is in use,” said Loman.
He said bigger studies are needed to help scientists “get a good grip” on this.
Professor Robin Shattock, head of mucosal infection and immunity at the Department of Medicine, Imperial College London, stressed that vaccines remain effective on the new CCP (Chinese Communist Party) virus variant, even if their effectiveness is reduced.
“At the moment there’s some evidence that some of the vaccines are slightly less effective against the new variant, but that doesn’t mean that they’re not effective.”
“There’s a distinction between preventing any infection and preventing serious disease. Something that’s transmissible more actively is harder to prevent getting any infection whatsoever, but the vaccines are still quite effective at preventing hospitalisation,” he said.