“This 3rd dose has a much wider immunological effect”, says a professor of medicine

“To defend yourself you have to respect barrier gestures and get vaccinated rather than telling yourself that you are going to close the borders,” said Jean-Daniel Lelièvre.

Article written by

Posted

Reading time : 2 min.

While the campaign for the recall of the vaccine against Covid-19 is launched, Professor Jean-Daniel Lelièvre, head of the infectious diseases department at the Henri Mondor Hospital in Créteil is reassuring, on franceinfo, Sunday, November 28: “This 3rd dose has a much broader immunological effect”. For this vaccination specialist, expert at the Haute Autorité de Santé and with the WHO, there is no reason to believe that messenger RNA vaccines will not be effective against the Omicron variant.

franceinfo: How can we reassure the population about the effectiveness of this recall?

Jean-Daniel Lelièvre: We must not wait. The arrival of a new variant is an indication to make this additional dose. When we do an additional dose of vaccine away from the first two, we will mobilize specific populations and we will allow to induce a fairly high level of antibodies. By stimulating these particular cells we will have a much wider diversity of the immune response. We do not know the sensitivity of the Omicron variant but, if we draw a parallel with the Delta variant, we know that the 3rd dose induces a much greater protection than the first two. This 3rd dose has a much broader immunological effect.

Laboratories announce work on a new vaccine. Why such a research?

The laboratories say that if we are faced with a variant that completely exceeds the immune response, we could make a new vaccine within three months. Take the example of the Beta variant, which is less talked about. The Moderna laboratory has carried out studies with a vaccine adapted to the Beta variant and the vaccine currently available. It was found that vaccination with the vaccine available today was about as effective as a new vaccine adapted to Beta. So, we must remain careful with the announcements of the laboratories. The RNA vaccines that we have at our disposal make it possible to have remarkable efficacy against the Alpha, Beta and Delta vaccines when they are not present in the vaccine. There is no reason to believe that it will not be the same with the Omicron variant.

This variant is present in many countries. Is it also in France, according to you?

It is most likely in France as was the case with the Alpha and the Delta. We must limit, as some countries have done, the arrival of the virus by blocking certain destinations. To defend yourself, you have to respect barrier gestures and get vaccinated rather than telling yourself that you are going to close the borders.


source site-14