The lower severity of the Omicron variant, compared to its predecessors, has been confirmed by a British study. But in recent weeks, a sub-variant has been spreading in the country: the BA.2 sub-lineage.
- Since January 25, contamination has dropped by 77%.
- Compared to Delta, the Omicron variant is associated with lower risks of hospitalization and death.
- In Denmark, the BA.2 sublineage became dominant.
The fifth wave of Covid-19 is slowing down in France. Contaminations are fewer and new hospitalizations are falling. At the same time, the scientific community knows more about the Omicron variant, which has caused this rebound in cases since the end of 2021. According to a study published in the scientific journal The Lancetit is confirmed that it is less severe than the Delta variant.
A less severe variant
This research, carried out by researchers from Imperial College London and the University of Cambridge, is based on the analysis of data from more than 1.5 million people infected with the virus between November 22 and November 9. january. About a third of them were affected by the Delta variant, and the others had been contaminated by Omicron. The scientists observed hospitalization rates, and death rates, depending on the mutation studied.
According to their conclusions, the risk of hospitalization in the event of contamination by the Omicron variant is 2.4 times lower, compared to Delta. The risk of death is 3.2 times lower. In people aged 50 to 69, this reduction is the most significant: the risk of hospitalization is divided by 4 and that of dying by 6.25. For the authors of this study, the reduced risk of dying from Covid-19 in the event of infection by Omicron, “will make the goal of living with Covid-19 easier to achieve, in the absence of public health interventions disrupting socio-economic life“, with one condition: that future variants have a similar level of severity.
The BA.2 sub-lineage: a new source of concern?
But for a few weeks now, the scientific community has been observing a sub-variant of Omicron, the BA.2 sub-lineage. As of January 31, it accounted for 10.7% of infections, down from 4.5% the previous week. According to the last point of Public health Francehe “remains a minority but on the rise”. This could be linked to its level of transmissibility: according to a study, published in the journal Nature, it is higher than that of Omicron. But according to scientists,BA.2 is unlikely to trigger a wave of infections, hospitalizations and deaths after the one sparked by Omicron.” TO The Express, epidemiologist Yves Coppieters confirms that there is little risk that this sub-variant will cause a new wave. “The BA.2 sub-variant only prolongs the Omicron wave, he tempers. (…) The reason is simple: immunity seems quite effective.“The next few weeks will make it possible to better understand the impact of this sub-variant and its evolution. For infectious disease specialist Benjamin Davido, who also speaks in The Expresshowever, we must remain cautious:Herd immunity will be transient and we will end up with different variants.“
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