The effectiveness of the flu vaccine today varies from 40 to 60% depending on the year and age group. So there is room for improvement. Remember that the flu vaccine is made from inactivated strains of the virus, so it is a weakened form of the virus that teaches the body how to defend itself.
A first innovation is already appearing this year: a new high-dose vaccine, produced by Sanofi, will be offered to people over 65 years of age. In this vaccine, the amount of active ingredient was quadrupled, which increases protection by 25%. This is useful for older people, as their immune system needs to be further boosted.
We also hear more and more about a messenger RNA vaccine against influenza. it would improve the efficacy of the vaccine and adapt to the emergence of new strains of influenza virus. It should only appear within two or three years – at best – estimates Professor Bruno Lina, virologist at the CHU de Lyon, because it will still be necessary to introduce four different messenger RNAs into the mixture to fight at least four families of viruses. influenza that coexist in winter. It is therefore still a little more technical than the vaccine against the coronavirus. In addition, we must keep in mind that developing a vaccine in just one year, as we did during the health crisis, is still very exceptional.
As for the combined influenza and Covid vaccines, why not. But here again there are uncertainties: we do not know whether it is effective to mix in the same syringe a messenger RNA vaccine against Covid-19 and a classic inactivated virus vaccine against the flu. Will we really need a booster against the Covid every year like the flu? Will there really be an interest in commercializing a combined vaccine? It’s still a bit early to tell.
The universal flu vaccine obviously doctors dream of. Because today it is indeed necessary to update the influenza vaccine, every year, according to the dominant strains circulating. The ideal would therefore be to use a fragment of the virus common to all strains to provoke an immune response that protects for several years. On paper it’s possible, but it’s technically complicated. For now, despite ten years of research, the universal influenza vaccine is still fiction.