The Covid-19 virus continues to change. Three cases of a new member of the Omicron family, BA.2.75 (called “Centaur”), were found in France on Friday July 22, 2022 (in Martinique, Occitanie and Grand Est), according to Public Health France.
While the BA.5 subvariant caused the seventh wave in France, this new version of SARS-CoV-2 has spread to many countries around the world. It appeared a few weeks ago in India, before coming to Europe.
Appeared in India, arrived in Europe
BA.2.75 was first reported in India in May and then spread to many other countries such as the USA, UK, Germany, Australia, Canada, Japan, or the Netherlands, which announced their first case on Wednesday July 13.
It comes from BA.2, which is a sub-variant of Omicron and was the most variant in France during the spring, when the sixth wave originated, before it was replaced in the early summer by BA .5 variant (at the beginning of the seventh wave).
BA.2.75 therefore qualifies as “second generation variant”. So far, there is very little information about him. This could be the initiator of a new wave in the fall (after the BA.4 and BA.5 sub-variants of Omicron).
A sub-variant under close surveillance
The World Health Organization has placed BA.2.75 on “blacklist” sub-variants to watch out for.
World Health Organization (WHO) chief scientist Soumya Swaminathan said the organization was closely tracking the strain, but there “limited ranges to analyze”.
He also gave some explanations in a video published in early July on the Twitter account of the United Nations special agency.
Soumya Swaminathan says that the subvariant “There seem to be multiple mutations in the receptor binding domain of the spike protein”. WHAT “an essential part of the virus that binds to the human receptor”he added.
“So we have to watch that. It is too early to know if this subvariant has stronger immune invasion properties and if it has more severe clinical effects, we don’t know yet”, determined the chief scientist of the WHO, indicating that the research will continue. In other words, scientists do not yet know the extent to which immunity can be avoided.
BA.2.75 was also listed on July 7 by the European Center for Disease Prevention and Control (ECDC) as a “varied under surveillance”.
The future dominant sub-variant?
The Dutch Institute for Public Health and the Environment (RIVM) declared in mid-July, specifying that little is known about BA.2.75, that it “It seems that it is also possible to easily evade the defense built against the SARS-CoV-2 coronavirus thanks to small changes”.
Antoine Flahault, director of the Institute of Global Health at the University of Geneva, meanwhile described theAFP that the spread of BA.2.75 in India indicates that it may be more transmissible than the BA.5 subvariant, leading to an increase in infections in Europe and the United States.
“It seems to be the dominant strain in India – the question is whether it will become the dominant strain anywhere in the world”he added, noting that the former dominant strains first dominated the country where they emerged before spreading around the world.
The expert, however, points out that there is a “margin of unpredictability”, and that it is too early to determine the gravity of BA.2.75. In addition, he added that successive variants make it difficult to create a vaccine to prevent them, because by the time a serum targeting them needs to be distributed, new strains are taken.
on CNews infectious disease specialist Benjamin Davido indicated on Monday July 25 that this sub-variant has a “infectious superiority”. He also emphasized the possibility of the arrival in French territory of this new variant accompanied by a decrease in the population’s immunity, which brings the risk of seeing it circulate and become dominant. “The majority of French people were vaccinated at the beginning of the year so we can imagine that the immunity in September is likely to be very low”. Not everyone knows about this sub-variant with an unofficial nickname.