The ninth wave of Covid-19 is taking shape in France.
According to Public Health France (SPF), 68,382 new cases of Covid-19 were confirmed this Wednesday, November 30 (+39% over seven days).
An increase partly due to the emergence of the BQ.1.1 sub-variant.
It is more precisely a sub-lineage of BA.5, itself a sub-variant of Omicron that SPF qualifies as “
ubiquitous
”
.
BA.5 represents 93% of Omicron viruses in circulation in France.
Note that only the Omicron variant is currently circulating in the country.
The specialists interviewed for this article agree that this BQ.1.1 sub-variant is largely responsible for the "
resumption of circulation
" of Covid-19 observed by SPF.
Be careful however, these data must be taken with caution, because of the recent strike of biologists.
This may have caused a data catch-up.
Read alsoThe oversaving of the Covid era remains in the woolen stockings
So what do we know about BQ.1.1?
Le Figaro
takes stock of this sub-variant which began to gain momentum last October.
• Will it become dominant in France?
Certainly.
“
Within two weeks to a month, if another sub-variant does not emerge
”
,
wants to believe Yves Buisson, epidemiologist and president of the Covid cell of the National Academy of Medicine.
In its December 1 weekly epidemiological bulletin, SPF claims that BQ.1.1 accounted for 49% of BA.5's sublineages in the week of November 7-13, 2022, up 15 points over three weeks.
“
This evolution of subvariants follows the classic pattern of viruses that tend to mutate.
The variant that emerges is the one that has the most tendency to be transmitted
,” recalls Yves Buisson.
Clearly, a sub-variant has every interest in being more contagious than the other sub-variants if it wishes to impose itself.
BQ.1.1 is about 30% more transmissible than BA.5.
“
There are over 500 subvariants in the world.
Some are essential and this is the case for BQ.1.1
”, confirms Antoine Flahault, epidemiologist and director of the Institute of Global Health at the University of Geneva.
Read alsoChina has not been able to get out of “zero Covid” and is exposed to more than 1 million deaths
Also in question, a mutation which "
causes a decrease in the effectiveness of antibodies, whether induced by vaccination or by a previous infection
"
,
assures Gilles Pialoux, infectiologist and head of the infectious and tropical diseases department of the Tenon Hospital (AP-HP).
A reinfection with Covid-19 can therefore occur more quickly.
• Is it more dangerous?
It's still hard to say.
According to the first elements available to specialists, BQ.1.1 would not be more dangerous than its parent BA.5, the currently dominant variant.
“
It is still very difficult to compare BA.5
and
BQ.1.1 in terms of dangerousness.
We can consider that it is about the same level as the other Omicron sub-variants
,
”
assures epidemiologist Yves Buisson.
Nevertheless, BQ.1.1 could have an impact on the most vulnerable people.
This sub-variant is said to be resistant to monoclonal antibodies, a treatment used in particular with immunocompromised people and the elderly.
“
BA.5 had already defeated many monoclonal antibody treatments
,” recalls Mircea Sofonea, lecturer in epidemiology at the University of Montpellier.
There, it will become even more difficult
”
.
Read alsoPaxlovid, an antiviral against Covid still too little prescribed
Is excess mortality therefore to be expected among this type of public?
"
That's the whole question
," asks epidemiologist Antoine Flahault.
But it is not impossible in the most fragile people infected with BQ.1.1.
»
.
• Do the vaccines work against BQ.1.1.?
In terms of transmissibility, BQ.1.1 may elude vaccines more than BA.5, although experts interviewed agree that real-life data is still lacking.
The new so-called bivalent vaccines, effective both against the original strain of Covid-19 and against the sub-variants of Omicron BA.1, BA.4 and BA.5 and which integrated the vaccination campaign last September, “
Should experience a maintenance of activity against serious forms and deaths
[compared to the effectiveness of vaccines against BA.5, editor’s note]”, advances infectious disease specialist Gilles Pialoux.
SPF also indicated on November 16 that it had “
no indication that BQ.1.1 is associated with a different clinical presentation or severity from the other Omicron sublines
”.
Vaccine efficacy against severe forms of BQ.1.1 may therefore be the same as against other Omicron subvariants.
The Moderna laboratory nevertheless affirmed on November 14 that these bivalent vaccines had "
demonstrated robust neutralizing activity against BQ.1.1
"
,
during a study carried out on approximately 40 people.
Auspicious.