By our reporter/ A sub-variant of Omicron has been detected in 57 countries now, the World Health Organization has said.
According to the global health watchdog, in some countries, “BA.2” accounts for over half of sequenced Omicron cases.
Some studies have suggested it could be more infectious than the original Omicron variant.
The new subvariant of Omicron, however, doesn’t appear to be more severe than the original, according to WHO.
According to a study in Denmark, the first country where the subvariant overtook the original, It appears more transmissible than the original Omicron strain and more able to infect the vaccinated but there appears to be no difference in disease severity from this subvariant, based on data from Denmark, says the WHO’s, Dr. Boris Pavlin.
“Looking at other countries where BA.2 is now overtaking, we’re not seeing any higher bumps in hospitalisation than expected,” he says.
Scientists in the UK and abroad are also closely monitoring BA.2, a sub-variant of Omicron.
According to them, at the moment there is much that is not yet clear.
It appears to have a growth advantage compared to the version of Omicron, BA.1, that has swept the globe. Analysis by the UK Health Security Agency suggests it could be substantial, although there is a risk of over-estimating growth advantage in the early stages.
What we know is that it is certainly growing as a proportion of overall cases in the UK, they said, adding that because of a quirk in how it shows up in test results, we can see the numbers of suspected BA.2 doubled in the week up to 24 January.
But at that point, the sub-variant still appeared to account for less than one in 20 cases.
But that contrasts to Denmark where it has become dominant.
A preliminary assessment by UKHSA did not find a difference in vaccine effectiveness, although it said there was no data yet available on severity.
But it is worth noting that Denmark has seen similar trends in terms of hospital admissions and intensive care as the UK has, suggesting BA.2 does not mark a sea-change in severity.
And even if it does become the dominant version of Omicron, it may not actually alter the trajectory of the pandemic in countries that have seen a big wave of BA.1. That’s because there could be cross-immunity – an infection with BA.1 could offer some protection against BA.2.
What we know is that it is certainly growing as a proportion of overall cases in the UK.
Because of a quirk in how it shows up in test results, we can see the numbers of suspected BA.2 doubled in the week up to 24 January.
A couple of experts have also given their views on BA.2.
According to Prof John Edmunds, professor in the Centre for the Mathematical Modelling of Infectious Diseases at the London School of Hygiene and Tropical Medicine, the new strain could become dominant in the UK within the next few weeks.
This, he said may well extend this wave of infection, or even lead to another peak.
The good news, he says, is that at present there is no evidence to suggest BA.2 is more severe than the original Omicron variant and vaccines appear to be just as effective against it.
Prof Jonathan Ball, professor of molecular virology at the University of Nottingham, on his part, said, early indicators suggest the vaccines will provide similar levels of protection against BA.2 as seen with the original Omicron variant. Whether or not BA.2 causes more severe disease will become apparent as more data is collected.
He adds: “Of course, it is important to keep monitoring the situation and try to gain a better understanding of how this variant behaves, but so far there is nothing in these early analyses to worry us unduly.”
It is one for the scientists to watch, rather than for the public to be alarmed about at this stage, according to them.
With agency report
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