Public-health officials in Britain have found a mutation of the British coronavirus variant that scientists fear could make it more resistant to vaccines.
A report from Public Health England (PHE) says the mutated form of the variant surfaced during recent genetic sequencing of the virus. “Preliminary information suggests more than one acquisition event,” says the report, which was released late Monday.
The British variant has been circulating in Britain since November and is now the dominant version of the virus in the country. It has also spread to several other countries, including Canada. Studies show it is more contagious and deadlier than the original virus.
The PHE report says the new version contains a mutation known as E484K, which is also found in the highly contagious Brazilian and South African variants. The mutation makes it easier for the virus to bind to human cells and evade antibodies. The report “suggests that the U.K. variant is now independently acquiring the E484K change,” said Jonathan Stoye, a group leader at the Francis Crick Institute. “Whether this change will provide significant growth advantages for the novel virus, causing it to predominate, remains to be seen.”
Lawrence Young, a virologist at the University of Warwick, said the report shows that “the virus is very likely to be adapting to our immune response.”
The South African variant has already proven to be slightly more resilient to the vaccines now in widespread use – those from Pfizer-BioNTech, Oxford-AstraZeneca and Moderna. Two other vaccines in late-stage development, from U.S. drug makers Novavax and Johnson & Johnson, also appear to be less effective against it. Novavax said clinical trials showed its vaccine is 85.6-per-cent effective against the British variant but just 60-per-cent effective against the South African. Johnson & Johnson said the level of protection of its vaccine is 72 per cent in the United States, 66 per cent in Latin America and 57 per cent in South Africa.
Dr. Young said there is a concern the South African variant could also reinfect people who have already contracted COVID-19 and recovered. “This is likely to be due, in part, to the E484K mutation, which may weaken the immune response and also impact the longevity of the neutralizing antibody response,” he said.
Julian Tang, a virologist at the University of Leicester, said that if this version of the British variant takes hold, “the recent reassurances from recent studies showing that the [Pfizer-BioNTech and Moderna] vaccines will still offer optimum protection against the original U.K. variant may no longer apply.” He added that, “unfortunately, the lack of control of these different variants in the U.K. may lead this population to become a melting pot for different emerging COVID-19 variants.”
Many countries, including Britain and Canada, have tightened border controls in an effort to stop the spread of the variants. But scientists said the PHE findings show such measures could be ineffective. “This report would seem to suggest that, under conditions of very high levels of virus replication, even the most stringent of border controls, although they may delay spread, are unlikely to prevent the appearance of new variants,” Dr. Stoye said.
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