The more infectious B.1.1.7 variant that has come to dominate coronavirus infection in the UK is evolving further mutations, which scientists say will make existing vaccines less effective at preventing infection.
Public Health England said in a technical paper that researchers have detected 11 UK cases of B.1.1.7 acquiring a mutation called E484K, which is present in the variants fuelling Covid-19 surges in South Africa and Brazil.
The news is worrying scientists, said Julian Tang, clinical virologist at the University of Leicester: “This E484K mutation is already present in the South African 501Y.V2 and Brazilian P1 variants — and is now thought to be the main mutation impacting on vaccine efficacy.”
The E484K mutation is still rare in the UK. The PHE paper said the 11 detections were among a total of 214,159 coronavirus genomes analysed. “Preliminary information suggests more than one acquisition event,” the scientists said, meaning that the mutation has occurred independently on several occasions.
But scientists are concerned that the mutated form of B.1.1.7 could spread rapidly if it has a selective advantage, because it can overcome human immune defences acquired by vaccination or prior infection with an older form of the virus.
Coincidentally, 11 cases of the 501Y.V2 variant from South Africa have been detected in England in people with no travel history. Tens of thousands of people will be tested in door-to-door “surge testing”, as public health officials try to halt its spread.