Donald Trump is stamping his feet. The precious antidote against the epidemic, the American president requires by November 3, date of the election to the White House. Impossible ? Vladimir Poutine, his Russian counterpart, is already claiming victory in the frenzied vaccine race where nearly 200 projects around the world are in the running. There is no doubt that science is advancing rapidly. In France, even the Minister of Health, Olivier Véran, hitherto silent on the issue, begins to talk about it, even if it is lip service, with extreme caution. So when is this vaccine due? Here is what you need to know in seven questions about this long-awaited protection, when we crossed the threshold of 25 million cases worldwide this Sunday.
What are the most successful projects?
If we exclude the Russian vaccine Sputnik V, developed according to specialists according to dubious protocols, seven projects are in the lead: four Chinese, two developed by old truckers in the sector, the American-German duo Pfizer and BioNTech and the Anglo-Swedish AstraZeneca associated with the University of Oxford; and one by Moderna, the new American star of biotechnology companies.
These seven have entered clinical phase 3. Crucial, this final step consists in evaluating their protective power on tens of thousands of volunteers. "We know that they elicit an immune response that seems adapted to Covid-19, decrypts Professor Jean-Daniel Lelièvre, head of the immunology and infectious diseases department at Henri-Mondor hospital in Créteil (Val-de-Marne). And, unlike the vaccines we had sought against Sars-Cov1 and the Seas ( Editor's note: two other coronaviruses ), we found that in animals, they did not tend to worsen the disease, it is encouraging . "
“We have never been so quick to find a vaccine, observes Christophe d'Enfert. For eight months, it has been a veritable avalanche of publications, we have reached nearly 100,000 articles, the vaccine development plans are completely upset, we see phases 1 and 2 combined, all this is completely new ”, notes the scientific director of the Institut Pasteur, which is also engaged in the battle.
When will it be available in France?
"The first doses could be produced at the end of the year and we can expect that significant quantities by the end of the first trimester or at the beginning of the second", indicates Marie-Paule Kieny, the president of the Covid-19 vaccine committee. Newly created, this body collects data from laboratories to inform the government in its decisions. "The production apparatus is in battle order", assures the Inserm virologist.
Will it be 100% effective?
Marie-Paule Kieny warns, however: “For this scenario to hold, these vaccines must still be effective and protect at least one in two people from infection, this is the bar that has been set. ". Only 50% efficiency? "It's true that this will not necessarily excite the crowds," smiles the scientist. But if these vaccines arrive when the emergency services are filling up again, and mortality is on the rise, there is something to think about. "
"The difficulty with Covid-19," she continues, "is that there are many asymptomatic infected people, but it is forgetting that we do not vaccinate only for ourselves, we also do it to protect other. "
Enough to stop the epidemic?
Breaking the dynamics of the pandemic is what all countries dream of, which are helplessly seeing their economy falter and the number of patients increasing inexorably. To stop the mad rush of Covid-19, specialists argue that it is necessary to be able to create the conditions for collective immunity, with 60% to 70% of the population protected against the virus. But are these vaccines the miracle solution? “No, tempers Marie-Paule Kieny, it will be one more tool, barrier gestures will remain essential. The vaccine remains however essential, according to Jean-Daniel Lelièvre, "if we want to be able to quickly control the epidemic".
Can research still fail?
Christophe d'Enfert remains cautious: vaccine research is full of pitfalls, "failure is always possible, we have seen it with HIV", he notes. The moment of truth is approaching: “For the three vaccines tested in the United States and which are the most advanced (AstraZeneca, Pfizer, Moderna, for which the recruitments of 30,000 volunteers have started), we could have first indications on their effectiveness from the end of October at the earliest, ”explains Marie-Paule Kieny.
But, notes the Inserm scientist, “it is not necessarily those who left first who will necessarily be the big winners in this mad race against the Covid-19. »An allusion to Pasteur? A product with few side effects, inexpensive (between 1 to 5 euros per dose), stable and deliverable everywhere, even in countries where refrigerators are rare, weighted with a solid scientific background, and without adjuvants, this is the bet that the French institute is making, which is working, in particular with the Cochin hospital in its phase I (tests of tolerance to the product). Is he keeping his chances? "Who knows, maybe later?" »Reacts, dubiously, the boss of an infectious department, who wishes to remain discreet.
Will it take several doses?
Several vaccines could find themselves in competition with the health authorities who will weigh the pros and cons at length before placing their final orders. “The big question mark is how long the post-vaccine immunity will last for all of these products. How often will they require reminders? explains Jean-Daniel Lelièvre. And, in fine, it is quite possible that we end up combining several vaccines. We will do the first injection with one, then the reminders with others, it's a pattern that emerges little by little. "
Will it be compulsory?
Not really clear, nor very readable? How will the French react to so much complexity? This is the last big hurdle to overcome. “With the antivax , it risks being cotton, already grimaces Jean-Daniel Lelièvre, it will be necessary to show a lot, a lot of pedagogy. »Making it compulsory then, is it possible as Australia plans to do it? "It would be a monumental error", electrifies the practitioner.