Reacción a "Reaction: three new recombinant SARS-CoV-2 variants detected"

At present there is no evidence that the recombinant forms described have any characteristics different from those already known for BA.1 or BA.2, especially in terms of severity or vaccine effectiveness. 

For one of them (XE) a possible increased transmissibility has been described in the UK, but the evidence is still weak. As we have learned earlier, we need to see the long-term behaviour to be able to estimate whether it will replace the dominant variant (BA.2). But above all we need to know the trajectory of this recombinant form in other countries where it is present. This comparative epidemiology will allow us to rule out local effects, as has happened in the past with other variants. None of these data (information on the long-term trajectory in the same country and the trajectory in other countries) are available. 

On the other hand, XE maintains the genetic make-up that BA.2 has in the spicule protein, so it is to be expected that vaccine protection will not be fundamentally different from what we see now. 

Finally, it is important to remember that the emergence of recombinant forms is not new, they have existed before and will continue to appear. They occur when two different variants infect the same individual at the same time, so it is to be expected that they will be more common in settings where the incidence is higher. This does not mean that it will have essentially different characteristics: it is just another way in which viruses generate variation. In fact, the WHO still classifies it as an omicron subvariant. 

As with other variants and subvariants, what is needed is continuous surveillance of variants, recombinant and non-recombinant, and integration with epidemiological and clinical data to quickly make decisions if necessary. In that sense, with omicron we had a pretty clear idea of its characteristics in less than a month. This is the way forward in order to be able to stay ahead of the virus, should the need arise. At the moment, this does not seem to be the case for the recently described recombinant forms (pending more complete results).