While the government is putting the package on the vaccine strategy, and that the pass of the same name should very soon replace the health pass, new cases continue to explode in France, in particular because of the Omicron variant, now in the majority.
There have never been so many French people vaccinated against Covid and at the same time, there are records of contamination among the population. The responsible is now well known: the Omicron variant. Much more contagious, this strain also seems to escape the immune barrier of vaccination more.
What protection?
LCI, who asked himself the question concerning the large number of cases of contamination despite the third dose, found an element of response in the mouth of the professor of public health at the Lille University Hospital, Philippe Amouyel: vaccine provides only 30-40% protection against Omicron. “The vaccine reduces the risk of contamination, but not in an absolute way,” said the scientist. However, a few days ago Olivier Véran stated in front of the deputies: “The vaccine reduces the risk of infection by 85%, including Omicron.”
For public health France, the truth is visibly between the two since its last risk analysis report, published this Monday, January 10 and city by France Inter, reports a protection against infection estimated between 37% and 86% with the third dose.
Effectiveness reduced after 10 weeks?
In fact, what currently seems the most debated is the duration of the protection conferred by this third dose. And it is perhaps she who would explain that patients, yet vaccinated with the three doses of the vaccine against the Covid, contract the disease.
“According to the latest analysis of Public Health England, the effectiveness of the booster dose decreases somewhat after ten weeks. Up to four weeks after the third injection, the protection was 65 to 75%. At ten weeks, this dropped to 40-50%“, analyzes Thibault Fiolet, epidemiologist at Inserm, with LCI.
Third dose needed
However, this booster dose is not necessarily useless against Omicron. In its latest report, Santé Publique France recalls that with two doses, the vaccine efficacy against Omicron is very reduced or absent, and further decreases over time after the second injection. “Conclusion for the body, the booster dose is necessary.
Still, the protection of vaccination against serious forms is reassuring. Public Health France estimates that with a third dose, the vaccine booster can reduce the risk of hospitalization by 70 to 88%, and by 98% that of developing a severe form of the disease.