He is accused by the British authorities of being partly responsible for the outbreak of new cases in the south-east of England, and his trace has already been found in Italy, the Netherlands, or even in Belgium.
But is this variant of the SARS-CoV-2 coronavirus, which appeared in September in the United Kingdom, also circulating in France?
Many scientists believe this is very likely the case.
Indeed, the movement of people possibly infected from one side of the Channel to the other had been authorized since this summer.
"It is quite possible, it is possible, that this virus circulates [in France]", soberly indicated Olivier Véran Tuesday.
But we cannot yet fully affirm this.
Virus sequencing
To understand, you must first explain what is called sequencing.
Every virus contains a genome, itself composed of nucleotides (nearly 30,000 in the case of SARS-CoV-2).
In France, the Institut Pasteur was the first to fully sequence the genome of this coronavirus, on January 29, 2020. But this pathogen has mutated regularly for nearly a year.
Some of its nearly 30,000 bases have been able to evolve, hence the appearance of variants with more or less different properties (transmission, dangerousness, etc.).
In total, in the world, "300,000 mutants of CoV-2 have been sequenced," said geneticist Axel Kahn last weekend.
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It remains to be seen whether this "English variant", suspected of being more transmissible, is circulating in France.
“We will find out, we are launching genotypic studies.
Over the past few days, 500 viral strains have been genetically analyzed and this variant has not been found, which does not mean that it is not circulating, ”Olivier Véran said on Europe 1 on Monday morning.
“We are going to look even harder,” added the Minister of Health the next day.
The idea is to recover the virus obtained during a sample, then to apply sequencing techniques to it.
“When we isolate a virus, we look to see if the sequence of its genome corresponds to a particular variant.
As we know the mutations associated with this English variant, we can see if there are any changes that correspond, ”points out the virologist Yves Gaudin, from the Institute for Integrative Cell Biology (I2BC) in Paris-Saclay.
"If you specifically want to see if it's the English variant, you know on which nucleotides among the 29,000 there were variations, so you just have to look at these places", adds Jean-Daniel Lelièvre, head of the infectious disease department of Henri-Mondor hospital in Créteil (AP-HP).
Massive screening in the North in January
On the other hand, we do not know precisely how the 500 strains mentioned by Olivier Véran were selected.
“The sequencing of a sample of 500 viruses isolated at random in France should give an idea of the circulation of this variant on French territory.
We can also focus on a sample of positive people who have returned from the United Kingdom, ”emphasizes Yves Gaudin.
VIDEO. The variant of Covid-19 has not been spotted in France, assures Véran
The geneticist Philippe Froguel proposes for his part an “immediate operational implementation of the SentiCov (viral sentinel) program for sequencing samples from infected people everywhere in France”.
That's good, a massive screening operation is organized in his department of North from January 11 to 16.
“We hope for 30,000 PCR tests in five days, or around 600 positives.
We are going to sequence all these 600 samples, ”the researcher assures us.
The health authorities have reportedly given their consent for this approach.
Is the mutated virus in?
To find out, the genome centers are proposing to the government the immediate operational implementation of the SentiCov (viral sentinel) program for sequencing samples from infected people everywhere in France with an open database https://t.co/4BD3xpijrR
- Philippe Froguel (@philippefroguel) December 21, 2020
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Philippe Froguel adds that the cost (around 50 euros per sequencing) will be financed by research credits.
“We don't ask anyone for money,” he argues.
"We won't know for a few weeks"
In the end, knowing definitively if this English variant is present in France could therefore take a little time.
"If the variant is present in our country, we will only know in a few weeks," said Etienne Simon-Lorière, researcher at the Institut Pasteur, to France Info.
“It's a question of time, resources, and interest too.
In France, there are more people working on the development of treatments than on the sequencing of viruses, ”said immunologist Jean-Daniel Lelièvre.
As proof, the French researchers publish on the online platform Gisaid only less than one genetic sequence per 1,000 identified cases. This is 50 times less than in the United Kingdom, where there is "a great tradition of sequencing the genome of respiratory viruses", indicates Yves Gaudin. In a press release published on November 3, the National Academy of Medicine had also deemed “crucial to have access to all the detected sequences of the Covid-19 virus accompanied by extensive metadata (date, place, age of the patient, sex ), as quickly as possible, and ideally in real time ”.
