Can France prevent a fifth Covid wave… On Monday September 6, 2021, the Institut Pasteur explained in a study that through a model using the latest data about the Delta variant, a new epidemic wave would be much harder to stop despite the high vaccination toll. They explain that faced with this virus strain, vaccination will not be enough, as the virus is more contagious and mostly resists more to vaccines.
How come? The virus’s reproduction rate considered at 4 by the scientists this past June, has been reviewed upwards by the Institut Pasteur and is said to be a 5 now. With such a rate, it would be necessary to vaccinate 95% of people aged 60+, 90% of people between 19 and 59, and 70% of people between 12 and 19 years of age. Percentages are not likely to be reached yet for some age groups.
But since then, the situation seems to have changed... So much that epidemiologists now sound more optimistic. For instance, hôpital de la Pitié-Salpêtrière parasitology unit head Renaux Piarroux - relying on the assessment of contaminations in schools - : "School started over a month ago. Covid-19 did indeed spread among children. But not as much as expected. Contaminations are even going downhill in children under 10 who are yet not vaccinated" he told our peers from Franceinfo.
The reason behind such optimism: a major fall in contamination tolls over the past weeks, and a strong vaccination rate within the adult population, up to 88% of first doses for people aged 18+ - according to Santé Publique France's latest data, and 86% as for second doses. "Immunity of the people is rather good", Piarroux adds. But vigilance should stay on: "now, the stake is to keep this immunity up", he explains.
Same assessment for Mircea Sofonea - epidemiologist and searcher at the Montpellier University: "The epidemic is now declining with a reproduction number between 0.8 and 0.9. Or to put it another way, 10 people contaminate less than nine. The virus keeps on spreading, but the situation is favorable. Last year, at the same period, the reproduction number was set between 1.1 and 1.3 at the beginning of the second wave, which is currently not the case", he told our peers from Franceinfo as well.
He goes on and explains this Fall: "it is very likely for curves to stagnate, or even go upwards in the coming weeks as the weather goes colder and days shorter. But the change of pace will not occur overnight". He concludes: "For the situation to reverse, we would need a new variant or a brutal change in the compliance with health guidelines. But, given the current knowledge, there is not threatening variant currently taking over the Delta and we are not in a situation of general relaxing of health guidelines".
As for François Balloux, teacher at the London University College, he told our peers from LCI there will very likely be "epidemic surges in the coming months and years, but I do not expect waves like we have experienced over the past 18 months". Sofonea added it is "what we are observing, it is a change of wave pace with a more neutralized spread pace with less strong extents".
What about the arrival of Fall and colder weather improving the spread of the virus? "Like last year, the virus will start spreading again. People will be more indoor and this is when we will see a new surge" Institut Pasteur epidemiologist and professor Arnaud Fontanet told our peers from LCI. "With the arrival of the first cold weeks, the transmission rate and the case toll are likely to go up. If we have to deal with a fifth wave, it will be more modest and far less intense than the previous ones. But non-protected vulnerable people will bear the cost of this resurgence", National Academy of Medicine Covid-19 Scientific watch cell president epidemiologist Yves Buisson warned in L'Express.
Note scientists have reminded that even vaccinated the French must “keep on complying with health guidelines” and wear a face-cover to lower contamination risks.
