past infection protects as well as a vaccine, large disease immunity study finds

A new advance in research on the coronavirus. We are as well protected against Covid-19 when we have been previously infected with the virus as if we have been vaccinated, according to one of the largest studies on this crucial subject for the management of the epidemic, made public. Thursday February 16. “Even if an infection gives protection which diminishes over time, the level of this (…) seems to be as long-lasting, if not more than that conferred by vaccination”concludes this work published in the medical journal The Lancet.

This comparison is based on the messenger RNA vaccines from Pfizer BioNTech and Moderna, which are among the most effective against Covid and are the spearheads of vaccination campaigns in many Western countries.

The work published in The Lancet is of an unprecedented scale: it compiles around sixty pre-existing studies, with a follow-up of several years which notably takes into account the emergence at the end of 2021 of the Omicron variant.

“Hybrid” immunity

These results do not mean that it is indifferent to be vaccinated or to be infected to acquire a first immunity. It is indeed much more risky to fall ill, especially among the oldest. However, this study gives a more precise view of what can be expected in the population from the development of an immune system. “hybrid”, as more and more individuals will have been both vaccinated and ill at least once.

“In the long term, most infections will strike people who are well protected against serious forms, following a previous infection, vaccination or both”, pointed out researchers, not involved in the study, in a commentary also published by The Lancet. These results therefore raise hopes that future waves of Covid-19 will result in low levels of hospitalizations, they conclude.