Triple vaccinated and infected with Covid-19: towards a “superimmunity”?

Triple vaccinated … and contaminated with Covid-19. With the arrival of the Omicron variant which is exploding the number of contaminations in France, it is the case of more and more people, including the unfortunate finalist of the primary environmentalist Sandrine Rousseau. On Twitter, she laughs at this “explosive combo” received in “the same day” early January.

But what is it really: is a person positive for the coronavirus, shortly after their booster dose, superimmunized? What are scientists saying about this?

On LCI, Prof. Alain Fischer, chairman of the vaccine strategy steering committee (COSV), has doubts. “If it is the same day, it comes down to having the infection alone or the vaccine alone “, he warns, however acknowledging some benefits. “It could be that the contribution of the booster dose and the contamination are added a little bit” Due to “local immunity” infection induced “that does not lead to vaccination”, continues the “Monsieur Vaccin” of the government.

At Henri-Mondor hospital in Créteil, Mathieu Vahemas is more direct. “The subsequent protection conferred by the two is not going to be infinitely greater ”, warns the immunologist. “Whether you are infected or vaccinated, you cannot make more antibodies than your immune system allows”, he indicates. In other words, “if your system is already stimulated to respond endlessly against the virus, it will not be able to go higher”, summarizes the scientist.

With this “super accumulation”, other scientists like Stéphane Paul, on the contrary see the birth of a “hybrid immunity”. “Vaccination and contamination allow you to obtain a greater overall response. On the one hand, you create antibodies, and on the other hand, you increase your chances of destroying infected cells that would snub your antibodies.”, notes the immunologist, drawing on immune reactions.

When a person is infected, “Its immune response involves a whole bunch of antigens and not just the Spike protein” located on the surface of the virus, “unlike vaccines which mainly produce antibodies against this single protein”, he explains.

To own this “hybrid immunity”, “however, it is more beneficial to contract the virus before receiving a booster dose”, explains Stéphane Paul. In this case, the Ministry of Health and Solidarity requests “to wait at least 3 months after the end of the symptoms before proceeding with the vaccination”, he says on his site.

Be careful, however, not to just want to be contaminated: the effectiveness after an infection “remains unpredictable“and alone, it does not mean sufficient protection. The booster dose, it certainly allows to limit the risks of reinfection and serious forms, insist the three scientists.