His name as he informally gave attributed Ryan Gregory, a biologist at a Canadian university, on social networks, it is also offa destructive monster from Norse mythology. Omicron’s subvariant, alias “Kraken” (officially referred to as XBB.1.5), circulated according to World Health Organization (WHO)in thirty-eight countries by mid-January 2023, especially in United Stateswhere it was the majority and represented more than 80% of the sequences performed.
This variant, which would have appeared at the end of October 2022, has already landed in Europe and is even developing quite quickly there: it represents 8.1% of the sequences in the UK and 2.2% in Denmark. In France, and according to data from Public Health Franceit has been circulating quietly for a few weeks and represents only about 2% of the pollution, while the peak of the ninth epidemic wave was reached and that a sharp decline had largely begun.
A Kraken in mythology looks like this. But the variant we’re talking about is actually a lot less scary. | Public domain via Wikimedia Commons
Should we worry about the Kraken’s arrival today? Yes, but without having any reason to fear it more than necessary. The occurrence of a new epidemic wave is never good news. We know today that it will be associated with a sad procession of new cases and long covidsbut also new admissions and new deaths among vulnerable people. No panic therefore, but no complacent fatalism either. We have been asked to “live with”, we would suggest that you try to “live better with” – that is, rather “without”, besides, you now know us.
X.BB.1.5 who are you?
Since we have become somewhat familiar with the large Omicron family, we allow ourselves to address the youngest of the siblings immediately – you will forgive us, it is that we have the impression of already knowing the offspring well. What do we know today about Kraken (XBB.1.5)?
First, let’s say that it is a subvariant of Omicron and, to be more precise, a descendant of the recombinant XBB subvariant of Omicron. In fact, in the naming convention for variants and subvariants of SARS-CoV-2, the prefix “X” denotes a lineage resulting from a recombination genetic of two subvariants. Thus, the XBB lineage most likely arose as a result of natural co-infection of a human host with two Omicron subvariants, namely BA.2.10.1 and BA.2.75. It was first identified by the public health authorities in India in the summer of 2022. And XBB.1.5 is the “fifth grandchild” of the parent XBB subvariant.
In fact, XBB.1.5 is part of the soup of more than 650 Omicron subvariants listed in the world to date. Many researchers consider it to be the most genetically mutation-rich and transmissible variant to date. These same scientists are to blame International Taxonomy Committee for Viruses by the WHO to have stopped for a year in naming the new variants of the Greek letter Omicron and to embellish its sub-variants with a series of letters and numbers incomprehensible to the general public. They therefore decided, as mavericks and quite unofficially, to give them nicknames.
Don’t panic: more transmissible does not mean more virulent
All these nicknames should be easier to remember, so it’s with good intentions. However, the choice of these nicknames still makes sense. Ryan Gregory did not offer names flowers or painters, but monsters destined to provoke fear. But if some like to get scared and fear the consequences of a crazy variant and to suggest disaster movie scenarios, we must be right.
Actually remember that RNA viruses is known to mutate frequently, and the coronavirus, whose circulation is planetary and massive, has accustomed us to see the emergence of many subvariants in three years. The variants that emerge and impose themselves, replacing their predecessors, are expected to win these tournaments precisely because they are more transferable.
We experience the classic evolutionary processes in the biological world at an admittedly accelerated, because planetary pace. So as long as SARS-CoV-2 is not eradicated or even contained, the increased transmissibility of one variant taking over from others, even highly circulating ones, is not a surprise.
We can almost say that any new variant that becomes dominant in the current context will be more transferable and will necessarily escape more immunity hybrid already very widespread in the population. There is therefore no reason today to believe that the series of epidemic waves that we have faced for three years, and which even accelerated in 2022, will soon end spontaneously.
Increased portability means a reproduction rate higher, where the latter is the number of secondary cases per infected person. But the level of transmissibility of a strain tells us nothing about its virulence. However, a disaster scenario, as we mentioned above, would consist of the emergence of a new variant that is both more transmissible and more virulent.
Obviously, the increased virulence of a new variant would worry us. However, there is currently no evidence that XBB.1.5 causes more complications and severe forms than its predecessors. Actually, when you look at it hospitalization curve for Covid in New York, where it is the majority, we can clearly see an increase in hospitalizations between the end of November 2022 and the beginning of January 2023 (with a curve of deaths that followed). But these levels thankfully remain very low compared to those reported during the waves of January 2021 and even January 2022 (due to the first BA.1 variant of Omicron).
Admissions are increasing, but are far from the level from the winters of 2022 and 2021. | Screenshot state of New Yorkfrom 23 January 2023.
These hospitalizations, a true reflection of the severe forms of Covid-19, worry, as we now know, the elderly if not very old and therefore particularly vulnerable to infection because of their age and immunosenescence as follows. But the peak of the New York wave linked to the Kraken seems to have been reached in the last few days: the curve for admissions is falling. In other words, let’s stop predicting a “destructive wave”. New York did not experience it, Western Europe has no reason to observe it.
And if we were inspired by the rich?
It is difficult to distinguish between the intrinsic increase in transmissibility and that associated with immune escape due to mutations in the strain. We recognize that there are still questions today about XBB.1.5’s ability to avoid vaccines and against monoclonal antibodies. The New York experience is also of great use to us here, because we have not seen young people who have been properly vaccinated flock to hospitals.
Vaccines continue to provide strong protection against severe forms of Covid-19. Unfortunately, one by one, monoclonal antibodies have lost their effectiveness in the face of these new variants and have become useless. Good news on the side of antivirals, including Paxlovid is the leader: there are no pharmacological reasons why their activity is altered by the mutations observed on the subvariants of Omicron. So to this day it is not legitimate to wave multiple red flags.
But make no mistake, the idea is in no way to say that we should sit on our hands. You know us well enough not to even suspect that we would insinuate it. We believe that those who constantly cry wolf run the risk of being counterproductive. A continuous dramatization could even end up mithridatizing us and evoking a kind of fatalism that would deprive us collectively and individually of our agency. The time may not be to stay in this kind of permanent emergency we have known, but rather to orient ourselves from now on to implement what we know how to do less good, that is, prevention and anticipation.
Whether XBB.1.5 threatens and takes advantage of the break in France to tumble loudly, in a few weeks or a few months, or whether it is the work of another more competitive variant, which is the result of the soup of the 650 candidates in spring, we know that we will not be powerless to respond proportionately when the time comes. The risk is always present, and as we said on January 16the pandemic is not over.
Instead of playing a dilatory way to scare us about the arrival of these new variants, let’s instead use our energy and our resources to try to do better in terms of prevention and risk reduction. No pollution is trivial, those who suffer from Covid for a long time, or who are hospitalized for serious complications know something about it. It is in all our interests to avoid getting infected again as far as possible.
The actions that should be taken today are those aimed at reducing the risks pollution in closed places. Look at what the rich do, those who think their importance prevents them from getting sick. On Davos World Economic Forumwhich took place from 16 to 20 January 2023, all participants wore masks and was tested, and those who were positive saw their badge instantly disabled and no longer had access to forum activities. The meetings took place in rooms equipped with air purifiers and many interior rooms were furnished with UV-C lampswith documented virucidal activity.
Yes, this is how you should behave in closed, crowded places where you spend time. Because of the cold, organizers could not ventilate all rooms effectively, so they resorted to risk reduction methods. Perhaps soon we will have epidemiological results from the PCR carried out in Davos and will be able to evaluate these different protective agents.
We repeat it again: Air quality is important
What the leaders of this world are asking for is exactly what each and every one of us needs today schoolshospitals, prisons, bars, restaurants, clubs, public transport and meeting rooms. Regardless of where we are in closed places, we would like to be able to benefit from air of acceptable microbiological quality, that is to say significantly reduce the risk of getting Covid, flurespiratory syncytial virus (RSV) or tuberculosis.
When the virus circulates strongly in society, we will also remind you of that the importance of wearing a mask in closed public places, including public transport. We will reiterate how important it is keep up to date with your vaccination reminders and how necessary it is for antiviral treatments to be prescribed for the most vulnerable people as quickly as possible after their infection. For this we must continue to test them at the slightest symptom. Finally, we will insist on the need to have quality surveillance of health in each country to enable the authorities to better anticipate the development of this pandemic.
Whether it is XBB.1.5 causing a tenth epidemic wave or another variant, whether they are called Kraken or Daisy, the question that should rather be asked is whether we do everything to be able to say, without boasting or complacency: “Me, not even scared!”