People vaccinated against Covid-19 who were infected with the first subvariants of Omicron have four times the protection of those who received the vaccine but were not infected, indicates a study published on Wednesday. According to the scientific community, the Covid-19 pandemic seems to be moving from a hyperacute phase to an endemic phase. But above all, it turns out that the current Covid-19 vaccines are less effective in blocking infection with the Omicron variant than in blocking infection with the earlier variants. But protection against serious diseases remains largely preserved. Hence the primary interest of anti-Covid-19 vaccines in providing long-term protection against the risks of hospitalization and death. It is therefore important that studies of Covid-19 vaccines and boosters assess not only short-term virus-neutralizing antibody loads, but also the duration of antibody responses, memory B cell responses, and cell responses. cross-reacting T cells. It is in the context of this issue that a new study was unveiled this week which will be a reference in the matter. According to the Institute of Molecular Medicine (iMM), based in Portugal, this is one of the first studies in the world to analyze, in a group of vaccinated people, the probability of being infected with the subvariant currently in circulation, BA.5, by estimating the degree of protection conferred by infections on the prior variants. It appears that “vaccinated persons who have been infected with the Omicron BA.1 and BA.2 subvariants have protection against infection with the BA.5 subvariant (in circulation since June) approximately four times greater than that vaccinated people who have never been infected,” explained Luís Graça. principal researcher at IMM and full professor at the Faculty of Medicine of the University of Lisbon. The results of the study were published on Wednesday in the scientific journal New England Journal of Medicine. Still, according to the expert, the infections recorded in 2020 and 2021 by ancestral lineage variants, such as Alpha and Delta of SARS-CoV-2 “however provide protection against infection with the newer Omicron variant”, although not as high. In comparison to people infected with the BA.1 and BA.2 variants, early 2022. “These results are very important because the adapted vaccines that are in clinical development and evaluation are based on the BA.1 subvariant, which was dominant in January and February 2022,” said Luís Graça. The specialist, who is part of the Technical Commission for Vaccination against Covid-19 (CTVC) of the General Directorate of Health (DGS) in Portugal, emphasizes that “these results show that protection is very important that they above all allow ‘anticipate the benefit of appropriate vaccines’ against Covid-19, added Luís Graça.