New Covid UK variant ‘dominant’ in France by March

The new variant of Covid-19 that was first identified in the UK is predicted to become “dominant” in France between the end of February and the middle of March, health research experts have found through a new genetic study.

A new two-day study by public health research organisation Inserm looked at PCR test results over two days from January 8. Through genetic sequencing, it showed that the new variant represents, at this point, 1.4% of positive tests in the country.

Based on these results Inserm estimated that the new variant could “become dominant” in France by “the end of February to mid-March”.

This is also based on the data that already exists on the new variant, which shows that it is between 50-70% more contagious than the previous strain. It is likely to become more common in France over the next few weeks, until the majority of new positive cases are of the new variant, Inserm said.

Based on this trend, professor Jean-Daniel Lelièvre, head of infectious diseases at Henri-Mondor Hospital in Créteil and a vaccine expert for the Haute Autorité de Santé, believes that a third lockdown, in some form, is inevitable.

“Will it be regional, national? Do we have to do it all over the country? We will have to see with the epidemiologists as we go along,” he told radio network France Inter on Sunday, January 17.

He said that in any case it should not be put in place until at the earliest after the half-term holidays in February and that the country should wait to gauge the effects of the 18:00 curfew.

“Even if we delay the lockdown, we must remain cautious and respect social distancing for the weeks to come,” he said.

French Prime Minister Jean Castex said during a press conference on January 14 that a third lockdown would be put in place without hesitation if the Covid-19 situation got worse. However, he said that currently there was no need for such a measure.

Hospitalisations could reach 20,000 per week

The Inserm study aimed to predict the spread of the new variant and estimate the possible future level of hospitalisations.

It found that without appropriate measures, the peak of the first wave could be reached by the end of March, as a best-case scenario (where the epidemic is stable, and the contagion is at 50%).

Worst-case scenario, the number of weekly hospitalisations could reach 20,000 from mid-February (if the R number rises to 1.2; and the contagion is at 70%).

It used genetic sequencing on each PCR test included in the study, via a “screening” method of a brand of tests called Thermofisher. It can identify three virus genes, but can only identify one if the new variant is present.

This allows researchers to see which tests are likely of the new variant - although the method is not foolproof and can show some false positives, which the researchers take into account.

In any case, Inserm said that the country would see “a significant increase in cases [of the new variant] in the next few weeks” ahead of it becoming dominant.

Professor Jean-François Delfraissy, president of government advisory body le Conseil scientifique, told news service FranceInfo: “If we do nothing, if we do not make some very quick decisions, we will see a spread of the UK variant.”

Read more: Is the UK’s new Covid variant spreading in France?

Inserm has not yet tested for other reported variants of the virus, such as that first found in South Africa.

Yet, the study authors said: “These results show the importance of enforcing physical distancing measures and accelerating the vaccination campaign to face up to the threat of the new variant.”

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