A mutation that enables Covid-19 to escape antibody protection has now been found in samples from a rapidly spreading strain in the UK, according to a report by Public Health England on Monday.
The mutation, called E484K, was already part of the genetic signature of variants linked to South Africa and Brazil.
According to the PHE report, the mutation was newly detected in at least 11 samples of the British B.1.1.7 strain. It also appears that some of these samples may have acquired this mutation independently, rather than spreading from a single case.
This could mean that a variant that is already known to be more transmissible may also have some resistance to the immune protection offered by vaccines, or that people who were previously infected are more likely to re-infect , say experts.
“This does not appear to be good news for vaccine efficacy,” said Joseph Fauver, an associate researcher in epidemiology at the Yale School of Public Health.
He added that the new finding is also something to monitor in the US, where efforts to search for variants by genetic sequence are lagging behind in the UK. ‘The fact that we only saw it in the UK could be a result of their robust genomic monitoring program,’ Fauver said.
Experts believe it is too early to predict whether this development will greatly affect the trajectory of Covid-19 in the UK and around the world.
Previous studies suggest that E484K may be the main culprit for why certain vaccines seem less effective in South Africa. Laboratory research has also shown that antibodies are less able to bind and neutralize ear proteins due to the mutation.
Novavax recently announced that its vaccine was 89% effective in its Phase 3 UK trial, but it was only 60% effective in a separate Phase 2b study conducted in South Africa. Similarly, in the Phase 3 trial of Johnson & Johnson, the efficiency differed by country: 72% in the USA compared to 57% in South Africa. In both trials, 90 to 95% of cases in South Africa were linked to the B.1.351 variant, which contains the E484K mutation
Paul Bieniasz, a virologist at Rockefeller University, noted that the E484K mutation has appeared sporadically in multiple samples for months, but until recently it did not appear to be an advantage for the virus in populations without existing immunity.
But this is a different story in places like South Africa, where many people were previously infected. Dr Anthony Fauci remarked on Monday that a very high re-infection rate to the point where it appears that you are not infected, with reference to the work of colleagues in South Africa.
The B.1.1.7 strain first spotted in the UK has now been found in at least 70 countries worldwide, including about 470 known cases in the US, according to the US Centers for Disease Control and Prevention.
Experts believe that aggressive testing, compliance with Covid-19 guidelines and the introduction of vaccines are more important than ever in the light of these distribution variants.
“We need to vaccinate as many people as possible,” Fauci said earlier. “While there is reduced protection against the variants, there is enough protection to prevent you from contracting serious illnesses, including hospitalization and deaths.”