NEW COVID VARIANT. Originating from India, a new sub-variant of the Omicron variant dubbed Variant Centaure (BA.2.75) was detected in 12 people in France. It is closely monitored by the WHO because it would be more dangerous than the others. Symptoms, mutations, dangerousness, vaccine… What we know to date.
[Mis à jour le 1er septembre 2022 à 9h51] Under the radar of the health authorities: a new mutation of the Covid. Appeared in India since May 2022, the new sub-variant of BA.2itself a subvariant of Omicron, was detected in France for the first time in July 2022: it is the subvariant BA.2.75also nicknamed “centaur variant” (or “centaurus” in English) unofficially. “It seems to become the dominant strain in India – the question is whether it will become the dominant strain all over the world“, indicates Antoine Flahault, director of the Institute of global health of the University of Geneva to AFP. In France, there would be a little more than 10 cases detected. He is closely monitored by health authorities, such as Public Health France or the World Health Organization (WHO). How many cases to date? Where in the world ? What specific symptoms would they cause? Would it be more dangerous than the other sub-variants? Knowledge to date.
Definition: what is the Centaur variant, sub-variant of Covid?
The BA.2.75 mutation or the V-22JUL-01 sublineage (nicknamed Centaur or Centaurus, unofficially, that is, the health authorities do not call it that) is a subvariant of BA.2, itself a subvariant of the Omicron variant of Covid. The BA.2 sub-variant was the majority in France until mid-June 2022, but was gradually replaced by the BA.5 sub-variant, indicates Public Health France. “The BA.2 is a subvariant of Omicron, who is himself a “little cousin” of the Omicron variant“explained Jean-François Delfraissy, president of the Covid Scientific Council, at the microphone of France info in January 2022.
Is the Centaur sub-variant more dangerous than the others?
The replication capacity of BA.2.75 in the lungs would be greater than that of BA.2 and BA.5.
“If it is still too early to know if this subvariant has stronger immune invasion properties and if it will have more severe effects clinically, we do not know yet. [Cette souche] would be followed closelyby the World Health Organization (WHO), says WHO chief scientist Soumya Swaminathan. According to Public Health France, the subvariant “BA.2.75 was spotted by the international community of bioinformaticians and virologists because it carries a significant number of additional mutations in the Spike protein (K147E, W152R, F157L, I210V, G257S, D339H, G446S, N460K, R493Q reversion…). Nowadays, no data indicating that BA.2.75 possesses different characteristics other BA.2 sub-lineages“. In other words, the centaur variant would not be more or less dangerous than the other BA.2 sub-lineages. Other research is ongoing, such as a study conducted on hamsters whose results have been pre-published on Biorxiv.orgshowing that the replication capacity of the BA.2.75 in the lungs was superior to that of BA.2 and BA.5. The BA.2.75 variant had also caused viral pneumonia in hamsters.
What is the origin of the Centaur variant?
In its risk analysis on the variants emerging from SARS-CoV-2 of July 6, 2022, Public Health France indicates that the majority of the sequences corresponding to the BA.2.75 subvariant come fromIndia. It was first reported in India in May and then spread to other countries: United States, United KingdomGermany, Canada, Japan, Netherlands, Australia, Nepal, Indonesia, New Zealand, Denmark, Italy, China, Luxembourg… And in France in July 2022.
How many cases of the Centaur variant are there in France?
As of August 30, 2022: 12 cases of BA.2.75 were detected in metropolitan France and a case in Martinique, reports the worldwide tracking of the scientist Raj Rajnarayanan.
- 6 in Occitania
- 3 in the Great East
- 1 in Ile-de-France
- 1 in Brittany
- 1 in Auvergne-Rhône-Alpes
What symptoms does the Centaur variant cause?
This sub-variant would have the same characteristics as the BA.2 and more generally the Omicron variant. It would therefore cause the same symptoms, namely:
- A significant tiredness
- cough
- Fever
- Headaches
- Muscle pain or aches
- Sore throat
- Runny nose
- Digestive symptoms: nausea, vomiting, diarrhea…
- Sometimes a loss of taste and smell
Is the Covid vaccine effective against the Centaur variant?
A priori yes, since the centaur variant has the same characteristics as the BA.2.
- HASafter two doses of vaccine, efficacy against symptomatic disease is 18% for BA.2
- After three doses efficacy against symptomatic disease is 74% for BA.2.
- Efficiency drops to almost 50% two and a half months after the 3rd dose for BA.2indicates a study of thebritish health agency published on February 25.
Sources: European Center for Disease Prevention and Control (ECDC) / Risk Analysis of Public Health France Variants / SARS-CoV-2 variants of concern and variants under investigation in England, UK Health Security Agency, 22 July 2022.