According to a new study from the Strasbourg hospital center, antibodies directed against the spike protein of the Covid-19 virus persist for up to 13 months after infection. Researchers have also shown that vaccination (even a single dose) can enhance protection against the original strain and the British variant but not against the South African variant.
Antibodies to Covid-19 virus spike protein persist for up to 13 months after infection
For several months, scientific studies have followed one another in an attempt to define the lifespan of antibodies neutralizing Covid-19. Last November, a study conducted by the University of Oxford mentioned immunity of up to six months when an Italian study announced in early May that antibodies neutralizing Covid-19 remained in the blood for at least eight months afterwards. an infection. This Thursday, May 20, 2021, a new French study carried out at the Strasbourg University Hospital affirms that the antibodies directed against the spike protein of the Covid-19 virus persist “ up to 13 months after infection “.
To reach this conclusion, the researchers followed 1,309 people for more than a year. Among all the participants, 393 had already contracted Covid-19. In a press release from Strasbourg University Hospital, scientists explain that on this last group, ” one year after infection, 97% of individuals kept their anti-S antibodies “. By comparing the number of re-infections that occurred during the study in this group with the number of new infections in the control group of 916 people, they realized that the risk of contracting the disease is ” reduced by 96.7% in people formerly infected “, thanks to” the long-term persistence of anti-S “.
Antibodies that neutralize the original virus, the British variant but not the South African
The study data also revealed that thirteen months later, the concentration of these antibodies in the body makes it possible to neutralize ” the wild virus (the original strain of SARS-CoV-2) and the British variant, but not the South African “. In addition, the researchers emphasize that vaccination (even in the case of a single dose) makes it possible to strengthen protection against variants by significantly increasing the amounts of antibodies. Finally, the study also reveals a difference between the sexes since the antibodies directed against the spike protein of the virus ” decline faster in men than in women “.
According to Professor Samira Fafi-Kremer, “ This large cohort study provides crucial information on antibody persistence and risk of reinfection “. While for now, the study has only been pre-published without peer review, it should continue for the next few months. ” We plan to extend the study to continue the follow-up at 18 months and 24 months to better assess the dynamics of the antibodies over the long term. »Explain the authors.