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The United Kingdom, all the cradle of the known, more contagious variant of the virus that causes Covid-19, has discovered a new mutation that affects certain strains of the disease, the same as those found in South Africa and Brazil, which further complicates. the European epidemiological landscape.
As if that wasn’t bad enough, the more contagious British variant of Covid-19 only got worse. British health authorities announced on 2 February that they had observed a limited number of strains on the outskirts of Liverpool and in Bristol representing the E484K mutation in the British variant. A total of 40 cases were apparently detected.
“This is the same S-protein E484K mutation in the British variant as the other South African, Brazilian and Japanese variants,” Julian Tang, a virus expert at the University of Leicester, told FRANCE 24.
According to Jonathan Stoye, a virologist and head of research at the Francis Crick Institute in London, the cases were not imported from any of the three countries. “What happened in Liverpool is that the British variant developed the E484K mutation independently,” Stoye told FRANCE 24.
The E484K mutation has attracted the attention of the scientific community because of the possibility that it could make current Covid-19 treatments, including existing vaccines, less effective. But this does not necessarily mean that the new form of the virus will spread faster.
Antibody resistance
‘The 501 change [in the first UK variant], increases the binding of the virus to the cell, thus making it easier to spread; and the 484 increases the resistance to the antibodies, ”Stoye explained.
There is another thorny demand for the virus’ resistance to antibodies and, in addition to vaccines, which stimulates the immune system so that it provides natural defenses against the disease.
When it was discovered in early January, the E484K mutation caused concern among immunologists because it altered the shape of the “peak” protein (which causes the virus to bind and contaminate the cells), which can complicate the task of the antibodies. .
The mutation “is likely to better enable the virus variant to evade the body’s blocking antibody response. It may also reduce the ability of current vaccines to protect against infections,” Lawrence Young, a virologist and professor of molecular oncology, told the Warwick Medical School, emailed FRANCE 24.
‘This may explain the recent results of the Novavax vaccine trials [that showed] While the vaccine was 95.6% effective against the original coronavirus and 85.6% against the British variant, it had an effectiveness of only 60% against the South African variant, ”he added.
Researchers and pharmaceutical companies have worked to better understand the implications of the E484K mutation. Initial findings show that vaccines may be slightly less potent, but “the key is that protection against the virus in people with a good immune response must still be effective,” said Stoye of the Francis Crick Institute.
But he added that the mutation is ‘particularly important for the elderly who have a lower immune response and produce smaller amounts of antibodies’.
That’s why it’s essential to get the vaccine injections close together, Stoye warned. The second dose increases the production of antibodies, which can be crucial in combating these new variants. “One shot is not enough. People need to understand that there is still danger after one shot with these variants,” he said.
The discovery in the UK of strains carrying the E484K mutation could weigh on the heated debate in Europe over the waiting period between two shots. Moderna and Pfizer recommend three weeks to one month between administration of the two doses, but several countries, including the United Kingdom and Germany, have suggested further excretion.
By extending the period, it will be possible to vaccinate at least once more people, without having to set aside too many doses for the booster. It amounts to a political decision, at a time when there is public pressure on European governments to speed up vaccination campaigns.
But scientifically, it’s risky: BioNTech has made it clear that the vaccine is 52% effective after the first dose. According to European recommendations (which require a minimum efficiency of 50%) it is hardly sufficient – but it only applies to the Sars-CoV-2, without any significant mutations. The British variant could quite possibly take advantage of governments’ efforts to calm and disperse their impatient ingredients.
This article has been translated from the original into French.