Like those who preceded him, he is eagerly awaited.
This Thursday, March 11, the European Medicines Agency is expected to vote on the Janssen vaccine, from the Johnson & Johnson group.
In the wake - Friday or Saturday -, in France, the High Authority of Health (HAS) will say for whom it recommends this fourth serum against Covid-19.
A breath of fresh air, despite a limited volume: only a million doses are expected in France in April.
“We need vaccines more than ever, loose Mylène Ogliastro, vice-president of the French Society of Virology.
The more the virus circulates, the more it mutates.
The more it mutates and meets resistance, the more it bypasses it and new variants are formed.
It must be overcome with a massive and rapid vaccination.
"
And yet, there is a long way to go.
The evidence in Israel, which has immunized with all its might, but does not rule out a fourth confinement to finish choking the virus.
In France, the figures are alarming: a little more than a thousand patients in distress are in intensive care for the Ile-de-France alone.
In the Alpes-Maritimes or in Dunkirk (North), where the weekend confinement is extended, hospitals are saturated.
But despite the situation, after the Health Defense Council which was held this Wednesday, March 10 at the Elysee Palace, no new restrictions seem to be considered for the time being.
All eyes are on the bottles and needles.
Some 6.4 million injections have been carried out since the end of December, and more than 4 million French people have already received at least one dose of the vaccine.
"We have the very strong ambition to accelerate the campaign," says the Ministry of Health.
“There are still unknowns, including the duration of immunity: how long does the vaccine protect us?
»Points out researcher Morgane Bomsel.
While waiting for answers and other candidates, three experts are helping us sift through the four vaccines already on the market, or in the process of being.
Pfizer-BioNTech, the pioneer
For who?
The first to receive the sesame from the health authorities, on December 21, the Comirnaty vaccine, born from the alliance between the American Pfizer and the German BioNTech, is now reserved for the most vulnerable patients.
"The most at risk of developing a serious form of Covid", summarizes the immunologist at the Paris Cochin Institute, Morgane Bomsel.
We find those over 75, who can receive their two doses 21 days apart.
From 18 to 74 years old, people with severe kidney disease, having received an organ transplant, Down's syndrome ... can claim it.
His technique?
Innovative, it is based on the so-called messenger RNA.
We introduce a genetic code that will give instructions to our cells in the event of a virus attack.
“As if we were giving them instructions to defend themselves,” explains Prof. Dominique Deplanque, pharmacologist and director of clinical research at the Lille University Hospital (North).
Unlike conventional vaccines, it is the body that does the job.
"
How many doses?
Three million people have already experienced it and 2 million have received the second injection.
According to the Directorate General of Health, 9 million doses are expected in March, making this serum the majority vaccine in France.
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Its more?
The effectiveness brandished during the tests (95%) is shown to be close to the first data in "real life", in Israel, for example, which observes a 92% reduction in severe cases.
Another varnish to his CV, he could considerably reduce the risk of transmission of the virus.
Still to be confirmed, this Israeli data would allow vaccination to a much larger audience.
Its flaw?
Storage between −60 and −80 degrees which makes its transport and storage very complicated.
According to a recent Italian study, it may be less effective in obese people.
Moderna, the innovative
For who ?
Like its elder Pfizer, validated two weeks earlier, the mRNA-1273 serum from the American laboratory Moderna is currently reaching a limited audience: those over 75, people with high-risk pathologies, caregivers / home helpers. / firefighters over 65.
Two injections, spaced 28 days apart, are necessary.
His technique?
He too is a messenger RNA baby, never used in human medicine.
This scientific saga began in California in the 1990s. In a few months, it has passed from shadow to light and is now raising many hopes.
How many doses?
Small thumbs up of deliveries, it has made it possible to vaccinate less than 300,000 people.
This must increase: 1.5 million doses delivered in March, 6.7 million in June.
Its more?
High efficiency, few side effects.
Like Pfizer, he resisted the English variant, but was shaken by the South African.
Never mind, the RNA technique allows it to adapt.
Moderna is thus working on a modified version of its vaccine, a "special" mutation, and says it is ready to test it on humans.
Its flaw?
"Its cost," replies virologist Mylène Ogliastro.
Like all
messengers
, it is expensive, which makes its access around the world unfair.
"
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AstraZeneca, the most practical
For who?
First suspected of being ineffective in the elderly, the AZD1222 of Swedish-British AstraZeneca is now dubbed in all age groups.
In addition to the over 75s, treating physicians - who will be joined on March 15, and from Thursday in the 23 departments under reinforced surveillance, by pharmacists - can inject the two doses to 50-74 year olds with comorbidity: obesity, hypertension blood pressure, diabetes ... All with nine to twelve weeks of difference.
His technique?
More classic, it is said to be “viral vector”.
We rely on another virus - here an adenovirus affecting the chimpanzee - modified and attenuated.
Its role is to trigger an immune response in the event of infection with Sars-CoV-2.
How many doses?
Despite a crisis last weekend, it has immunized less than 800,000 people.
Six million doses are expected this month, nine million in April or even 17 million in May.
Its more?
Very easy storage, in conventional refrigerators.
“We are finally sure of its great efficiency, greets Dominique Deplanque.
If you ever get sick despite the vaccination, the chance of you being hospitalized is reduced by 94%.
The contract is fulfilled!
"
Its flaw?
Some 2000 declarations of side effects "often of high intensity", according to the Medicines Agency: fever, body aches, headaches.
Professor Ogliastro will not say the opposite, she too was "KO".
“But it passed in 24 hours and paracetamol, nothing compared to the benefit.
"
VIDEO. Here are the differences between the 4 vaccines that will be massively distributed in France
Janssen, the single dose
For who?
After the European authorization, in France, it is the High Authority of Health (HAS) which will recommend a target audience for the Janssen serum from Johnson & Johnson.
"It will probably be the same population as for the AstraZeneca vaccine," anticipates Professor Deplanque, who hopes for rapid expansion.
His technique?
Like "AZ", it is viral vector, but this time, it is human adenovirus which is used.
"It is a virus which circulates in humans, triggers colds but against which we declare a natural immunity", notes the virologist Mylène Ogliastro.
How many doses?
Today zero, the vaccine is not yet validated.
France "demanded a first batch of delivery in April," said the Ministry of the Economy.
But his objective of receiving 2.7 million was then reduced to 1 million ...
Its more?
It is the only one that requires only one injection.
"This makes it more accessible, including for African countries, for example," notes immunologist Morgane Bomsel.
Its promoters ensure that it is effective against variants.
We have to check, but we will not shy away from this pleasure.
"In France, around ten hospitals are testing it, in Bordeaux, Saint-Etienne, Paris ...
Its flaw?
It too could cause a bit of fever, fatigue or headaches.
Answer soon, his adventure has only just begun.