Since the beginning of December, a new variant of the SARS-CoV-2 coronavirus has been identified in the United Kingdom. Called B.1.1.7, this new strain appeared after several mutations of the virus.

The new variant is more contagious

In the evolution of a virus, mutations are not exceptional events. But those that led to the B.1.1.7 variant are the first to stand out in the history of SARS-CoV-2. Because until now, the recorded mutations had no significant effect on the transmission of the virus, its severity or on the dynamics of the covid epidemic.

But the new strain seems more contagious and could even explain the acceleration of contaminations observed in December in England.

According to Neil Ferguson, epidemiologist at Imperial College London cited by the New York Times, this new variant has an increased transmission rate of 50 to 70% compared to other strains present in the United Kingdom.

Read also: Covid: should we be worried about mutations in the virus?

Children would be more sensitive to it

The increased transmission could be due to the way the virus infects children. Normally, children are less likely to be infected or transmit the virus than adolescents or adults.

But the new strain could make children “as sensitive as adults“to the covid, told theReuters agency Wendy Barclay, UK government adviser and virologist at Imperial College London. Analyzes are underway to confirm this hypothesis.

It doesn’t seem to cause more severe forms

While B.1.1.7 appears to be more contagious, it does not appear to cause more severe forms of covid. But this eventuality must be taken seriously.

In fact, in South Africa, a variant close to the B.1.1.7 variant was observed. It spread very quickly, and preliminary studies have shown that people infected with this strain have an increased viral load, that is, a higher concentration of the virus in their respiratory tract. However, viral load is often associated with the severity of symptoms.

Here again, studies are awaited to confirm or not this theory.

It is already present elsewhere than in the United Kingdom

This new version of the virus has already been spotted in Belgium, the Netherlands, Denmark, Italy and Australia, but to a lesser extent than in the United Kingdom.

In France, no patient carrying this strain has yet been identified. The numerous analyzes underway will make it possible to quickly identify its presence in the territory.

In any case, these different detections suggest that the new variant has already spread to several regions of the globe.

Vaccines would remain effective against this strain

For now, scientists doubt the mutation will have an impact on vaccines. Indeed, the effectiveness of the two vaccines Pfizer / BioNTech and Moderna already authorized in several countries around the world is based on the same principle: to create immunity against the coronavirus by teaching our immune system to recognize a protein which is on the surface of the virus: the spike protein, or protein S.

However, the S proteins of the new variant and the old one – against which the vaccine was developed – are 99% alike, Professor Uğur Şahin, CEO of BioNTech, told Reuters. There would therefore be very little risk that the shape of the S protein would differ from one variant to another. Very little risk, therefore, that the immune system of vaccinated people does not recognize the S protein of the new variant.

A hypothesis which should be confirmed within a few weeks, when the first scientific studies on the new variant will be published.
In the meantime, the experts are clear on one point: wearing a mask, washing hands and physical distancing remain effective against the new variant B.1.1.7.