Even if it confirms the other studies published on the effectiveness of the vaccine against Covid-19, this new publication produced by Epi-Phare, which associates the Health Insurance (Cnam) and the Medicines Agency (ANSM) is " largest conducted in the world ”with data on 22 million people.
Epi-Phare researchers compared the data of 11 million vaccinated people over 50 years old with those of 11 million unvaccinated people in the same age group, over a period from December 27, 2020 (start vaccination in France) on July 20.
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From the 14th day after the injection of the second dose, the researchers observed "a reduction in the risk of hospitalization greater than 90%", specifies the researchers.
"Vaccinated people have 9 times less risk of being hospitalized or dying from Covid-19 than unvaccinated people," explains epidemiologist Mahmoud Zureik, director of the Epi-Phare structure.
Data that confirms other observations made in real life in other countries, Israel, United Kingdom or United States.
Also effective against the Delta variant
Concerning 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 a 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 the first elements but "this period remains very short to assess the real impact of the vaccination on this variant".
"The study must be continued to integrate data for August and September," said Professor Mahmoud Zureik.
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This observation on the effectiveness of the vaccines is valid for those of Pfizer / BioNtech, Moderna and AstraZeneca (the fourth authorized in France, that of Janssen, was later, was used in smaller proportions and is therefore not included in the study).
Another positive point: the efficacy on severe forms of the disease “does not seem to decrease over the available follow-up period, which went up to 5 months.