What is this subvariant?
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Identified in July 2021 by scientists, the “AY.4.2” variant is a sub-variant of the highly contagious Delta which initially appeared in India and which had caused an epidemic resumption in late spring and early summer.
This sub-variant is defined by two mutations at the level of the Spike protein: Y145H and A222V.
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The appearance of new mutations is not surprising.
To date, there are 45 sublines of the Delta variant.
The perception that these variants are homogeneous is false,
François Balloux, director of the Institute of Genetics at the University College of London
According to him, the concern of the British authorities is linked to its frequency of appearance in the United Kingdom, which has increased by 7% in recent weeks.
Where is he present?
The AY4.2 subvariant has been detected in 27 countries and has infected 14,970 people worldwide, including 14,247 in the UK and 14 in France, according to outbreak.info figures from October 18.
The cases have been identified in North America, Europe, Australia and Japan.
The Delta “AY.4.2” sub-variant has infected 14,970 people worldwide.
Is it more transmissible?
The emergence of this new variant raises fears of an even stronger transmissibility.
It is the first sub-variant that is more transmissible than Delta.
Many hoped that we had reached a maximum rate of transmissibility with the Delta variant
, ”notes François Balloux.
He estimates that the rate of transmissibility could be 10% higher than the Delta.
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But, according to him, this new subvariant represents a lower risk of transmission than other strains.
Its emergence does not constitute "
a situation comparable to the emergence of the Alpha and Delta strains, which were much more transmissible (50% or more) than all the strains in circulation at the time
The situation "
is not dramatic
" and "
the slight increase in transmissibility will have little impact on the number of cases.
It is unlikely that it will change the current situation
, ”he adds.
Does the vaccine affect people who are vaccinated?
Despite its higher rate of transmissibility, "
there is little reason to believe that the sub-variant affects people who have been vaccinated
", reassures François Balloux.
Studies are underway to determine its resistance to the vaccine.