Paris (AFP)

Vaccination against Covid-19 reduces the risk of hospitalization and death by 90% in people over 50 and also seems effective against the Delta variant, on which we still lack perspective, according to a large French study alive actual published Monday.

"This means that vaccinated people have 9 times less risk of being hospitalized or dying from Covid-19 than unvaccinated people," epidemiologist Mahmoud Zureik, director of the Epi-Phare structure, told AFP. , which associates the Health Insurance (Cnam) and the Medicines Agency (ANSM).

To reach this conclusion, Epi-Phare researchers compared the data of 11 million vaccinated people over the age of 50 with those of 11 million unvaccinated people in the same age group, over a period of from December 27, 2020 (start of vaccination in France) to July 20.

From the 14th day after the injection of the second dose, the researchers observed "a reduction in the risk of hospitalization greater than 90%".

This observation applies to the vaccines from Pfizer / BioNtech, Moderna and AstraZeneca (the fourth authorized in France, that of Janssen, was later authorized, was used in smaller proportions and is therefore not included in the study. ).

"This reduction is of the same order of magnitude for the risk of death during hospitalization for Covid-19", according to Epi-Phare.

This efficacy on severe forms of the disease "does not seem to decrease over the available follow-up period, which went up to 5 months".

To identify the impact of the Delta variant, now dominant, the researchers specifically estimated the reduction in the risk of hospitalization during the period when it gained momentum in France, from June 20 ( therefore one month before the end of the study).

They found results comparable to previous periods: an efficiency of 84% in those 75 and over, and 92% in those 50-74.

This makes it possible to provide "initial elements", but "this period remains very short to assess the real impact of vaccination on this variant", warn the researchers, who are continuing their study to find out more.

These French data confirm other observations made in real life elsewhere in the world.

© 2021 AFP