A virus “mutant” offers the hope of a universal vaccine against influenza
peshkova
Published the 19.01.2018 at 18h01
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Keywords :
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Schematically, the influenza virus is surrounded by an envelope, where appear two proteins, which are specific to this virus. They are called H for hémaglutinine and N for neuraminidase. It is with a view to targeting that manufactures the vaccine.
Unfortunately, there are some variations in each year of their type : 19 H ; 9 for N ; this gives endless possibilities of virus, certainly of the same family, but different from an immunological perspective. This is why you have heard of influenza viruses under different names : H1N1 or H3N2… of Course H1 and H3, or N1 and N2 are the most common forms, but every year we do the top not immune to a mutation in surprise
Antigenic variation
Since the severe epidemic of 2009, the vaccine was fairly constant, but a new H3N2 strain, the origin of the epidemic of influenza important the winter of 2017-2018 in the northern hemisphere, has disrupted the vaccine this year
These changes, unpredictable, require the specialists of the vaccine against the flu to travel each year, as well as their virus, to spy on what happens in the real life of the southern hemisphere. Indeed, from the point of view of the flu, the winter begins in the southern hemisphere and it has the advantage of starting 6 months before the northern hemisphere, which gives us time to adapt the mixture of viruses for the vaccine. It is from these observations that consists the recipe for the vaccine to come in the northern hemisphere, the next winter.
It may seem a technique that is a little antiquated, since the effectiveness of the vaccine is never perfect and varies between 60% in good years compared to 30% bad. The researchers acknowledge, but they had no other choice of procedure.
A new technique
It is the Science magazine, which the announcement. Researchers have modified a virus of influenza, so that it causes – animals – reactions of defence is extremely powerful. Several attempts had failed. It seems that the last one is the correct one, and that it takes finally, with this altered virus, the element that was lacking in the manufacture of what we call the universal flu vaccine. A vaccine in which a single injection will protect against the flu several years.
Recall that the issue is size : the flu is key, according to WHO, 5 million people in the world. The need for an annual vaccination is without doubt the main obstacle to mass vaccination. Which may be soon the case. It speaks when even only a few years, because the precautions are going to be important to produce a vaccine to which the distribution will be massive and global.