France should keep a very close eye on travellers arriving from the UK due to the risk of the Indian Covid-19 variant, medical experts have said, as its spread in France could lead to another rise of the epidemic.
In a statement this week, government scientific advisory body le Conseil scientifique said: “[There is] a risk of around one person infected with the B.1.617.2 [Indian] variant arriving in France everyday.”
The variant - of which there are three subgroups, B.1.617.1, B.1.617.2 and B.1.617.3 - currently makes up 50% of new cases of Covid-19 in the UK, the latest figures from Public Health England (PHE) show; although case numbers in the country are low, at around 2,000-3,000 new cases per day.
The Indian variant is considered to be more contagious than other strains.
So far existing vaccines against Covid-19 appear to be somewhat effective against the Indian variant – if not as effective as towards other strains, such as the UK variant.
A study published on May 28 by research unit l’Institut Pasteur, found that mRNA vaccines such as the Pfizer-BioNTech, have a “slightly diminished effectiveness” against the Indian variant.
The study found that people who had had Covid in the past 12 months, or who had been vaccinated with both doses of the Pfizer jab, were protected against the Indian variant, but three - six-times’ less so than against the UK variant.
A recent study from PHE in the UK found that two doses of the AstraZeneca vaccine was 60% effective against the new strains.
Dr Mary Ramsay, Head of Immunisation at PHE, said: “This study provides reassurance that two doses of either vaccine [Pfizer or AstraZeneca] offer high levels of protection against symptomatic disease from the B.1.617.2 variant."
Yet, SPF’s studies found that a single dose of AstraZeneca was “not much or not at all effective” against the Indian variant. Two doses are required for any level of protection, it said.
In France, the latest figures show that 25,033,712 people have had a first dose of a vaccine; and 11,693,927 have had all necessary doses (one, two or three; depending on the vaccine given and the person receiving it).
Indian variant spread in France?
Experts have warned that a heightened spread of the Indian variant could lead to a reprise of the epidemic in France.
In a press conference on Friday (May 28), Daniel Lévy-Bruhl, epidemiologist at health body Santé publique France (SPF), said: “If the Indian variant does indeed have increased contagion and spreads widely in France, this could lead us to reconsider the relatively optimistic models we have for this summer.”
From May 31, visitors from the UK are only allowed to travel to France for essential reasons, which does not include tourism or those with second homes in the country.
Those who can travel must self-isolate for seven days upon arrival.
But the Conseil scientifique has said that self-isolation may not be enough to contain the variant, and said that "the key is to have a very active screening strategy via screening and sequencing".
This suggests that people from the UK should be tested and screened specifically for the Indian variant.
So far, the variant is rare in France, with 46 infection clusters so far confirmed, across 10 regions; estimates currently suggest that just 5% of cases are of the Indian strain.
Sibylle Bernard-Stoecklin, head of infectious diseases at SPF, said: “We have isolated a total of around 100 cases, but this figure is very under-estimated, as not all have been sequenced yet.
“We have found the Indian variant in...10 mainland French regions, especially Île-de-France and Auvergne-Rhône-Alpes.”
Of these 46 infection clusters, six have no links at all to India. So far, these have all been contained, SPF said.
Yet, the increase in the number of clusters is causing concern that the Indian variant could soon establish itself more permanently in France.
Different variants of the virus are only detected due to special sequencing of PCR test results, and this sequencing is only done when there is a significant risk factor, such as someone arriving back from India, or a contact of someone who has been infected.
And while France has introduced more widespread screening of PCR tests - especially due to the spread of variants such as the V1, V2 and V3 (UK, South African and Brazilian) - the Indian variant does not show up on these screening tests, due to its mutation.
Ms Bernard-Stoecklin explained: "The kits currently used in France for screening do not identify the B.1.617 variant, so they are generally classified as 'no variant'.
“These original strains have virtually disappeared in France and now represent about 4% of the results of screening tests (the English V1 variant is in the vast majority: 77%).”
These tests are now set to change “in the next few weeks”, Ms Bernard-Stoecklin said, with a view to detecting the mutations of E484K, E484Q and L425R, which are specific to the B1.617 [variant]″, which should better detect any Indian variant arriving in France from the UK.
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