In addition to spreading rapidly, this new mutation of the coronavirus was also becoming the “dominant” form in the United Kingdom, declared on December 19 Patrick Vallance, scientific adviser to the British government.

In addition, this new form of Sars-CoV-2 would have resulted in “a very strong increase” in the number of hospitalizations in December. According to Mr. Vallance, the mutation may have appeared in mid-September in London or Kent (south-east).

Read also: Covid: should we be worried about the new mutation that has appeared in the United Kingdom?

Faster spread

“The Advisory Group on New and Emerging Respiratory Virus Threats (NERVTAG) now considers this new strain may spread faster,” England Chief Medical Officer Chris Whitty said in a statement. communicated (in English).

This opinion is based on the observation of a “very sharp increase in cases of contamination and hospitalizations in London and in the South East, compared to the rest of England in recent days”, specifies the professor of medicine Paul Hunter, University of East Anglia, cited on Science Media Center website.

“This increase appears to be caused by the new strain,” he added, referring to information provided by health authorities. However, “there is no indication for the moment that this new strain causes a higher death rate or that it affects vaccines and treatments, but urgent work is underway to confirm this”, adds Chris Whitty.

A “much more infectious” virus

The information “on this new strain is very worrying”, according to Professor Peter Openshaw, immunologist at Imperial College London, quoted by Science Media Center. Particularly because “it seems 40% to 70% more transmissible”.

According to the World Health Organization (WHO), in addition to “preliminary signs that the variant could be more contagious”, the variant “could also affect the effectiveness of certain diagnostic methods”, again according to “preliminary information” .

“This is very bad news”, adds Professor John Edmunds, of the London School of Hygiene & Tropical Medicine: “It seems that this virus is much more infectious than the previous strain”. There is however “no evidence of a change in the severity of the disease”, although this point is also being researched.

What mutation?

On his Facebook page, the French geneticist Axel Kahn recalled that to date, “three hundred thousand CoV-2 mutants have been sequenced in the world”.

The new strain carries in particular a mutation, named N501Y, in the protein of the “spicule” of the coronavirus, the point which is on its surface and allows it to attach to human cells in order to penetrate them.

Read also: Coronavirus: contagion, severity, risk of mutation, the responses of a virologist

“Coronaviruses mutate all the time”

According to Dr Julian Tang of the University of Leicester, “this N501Y mutation was already circulating sporadically much earlier this year outside the UK, to Australia in June-July, to the US in July and to Brazil in April. “.

“Coronaviruses mutate all the time and it is therefore not surprising that new variants of Sars-CoV-2 are emerging,” recalls Professor Julian Hiscox of the University of Liverpool. “The most important thing is to find out if this variant has properties that have an impact on human health, diagnostics and vaccines.”

“The more viruses produced, and therefore the number of people infected, the more random mutations there are and the greater the frequency of mutations that are beneficial for the virus,” notes Professor Axel Kahn.

London and England re-confined

Confirmation of the contagiousness of this strain convinced the British authorities to order a re-containment of London and part of England (a total of 16 million inhabitants).

The European Disease Control Agency (ECDC), which includes around thirty countries including members of the EU and the United Kingdom, has “not ruled out” that the variant circulates outside British territory.

WHO has called on its members in Europe to “strengthen their controls”. Outside British territory, a handful of cases have been reported in Denmark (9), as well as one case in the Netherlands and Australia, according to the WHO.

Cut links with several countries

Several European countries, including Germany, France, Italy and Ireland, have announced the suspension of their links with the United Kingdom.

Berlin is also preparing air link restrictions with South Africa, where the same strain of the virus has been observed. Experts from the European Union have come to the conclusion that the current vaccines against the coronavirus remain effective against the new variant, the German government added.