– Omikron is now divided into some subgroups. One subgroup, called BA.2., Has so far been uncommon in the world. But now, after the New Year, it has increased quite sharply, including in Denmark and parts of Sweden.
Karoline Bragstad tells Dagbladet. She is a senior researcher and section leader at the Section for Influenza and Other Airborne Infections at the Norwegian Institute of Public Health (NIPH).
The subgroup is referred to as “an even more mutated version of the omicron” in FHI’s latest weekly report. It has already been discovered in Norway, and seems to be “on the rise” especially in Denmark, according to Bragstad.
– A more contagious
Bragstad does not rule out that the explanation, in whole or in part, lies in the fact that Danes are simply better at sequencing samples than other countries – and that BA.2 in reality is more widespread in other countries that do not sequence as much.
– This variant is not picked up in perhaps the most used screening method for omicron in Europe if this is used alone for screening, Bragstad says.
Therefore, the subgroup can go undetected until the samples are sequenced – which often takes longer, the senior researcher explains.
– There are few cases worldwide, but more than half of the cases globally have been in Denmark recently – and it seems to increase even faster than the original omicron variant. This indicates that it is even more contagious than the omicron variant we are familiar with. It is perhaps the one we are most on guard for right now.
So far, the National Institute of Public Health is not directly concerned – but they are following closely, according to Bragstad.
– We wonder if it might have an even greater contagion advantage than omikron otherwise. So we are following it closely now, to see how this degenerates.
– We have it in Norway
So far, there is nothing to suggest that BA.2 causes more serious disease than omicron in general, Bragstad emphasizes.
– But there are still few cases, she says.
– To what extent do you see BA.2 here in Norway?
– We have a few cases here in Norway, and several that we are about to confirm now. So we have it in Norway, and we will follow very closely how it spreads in Norway.
Results of the confirmatory tests are expected during the week. Several of the cases are known import cases from Denmark.
– We also see an increasing trend in Scania, which is closely linked to Copenhagen. Otherwise also in India and the Philippines.
– Is it possible that this virus will eventually be classified as a completely new variant of concern – with the corresponding Greek letter?
– It is by definition already a variant of concern, since it is defined as an omicron. But we can not rule out that it will get a different nickname eventually. Whether it will be “omikron plus”, “omikron extra” or what, it is unclear.
– It is only when you see changed properties in relation to the original omikron -BA.1 – that it will probably be considered to give it its own “nickname”, she adds.
– Know very little
BA.2. has many similarities with the original omicron variant, which now goes by the name BA.1.
– BA.2. has a few more mutation changes, and some changes we do not know very well, and have not seen in so many variants before. It has become very widespread in Denmark, only since the New Year. It seems that more than 20 per cent of all sequenced omicron cases detected in Denmark recently are now BA.2., And not BA.1. It therefore increases faster.
The question is whether it will eventually turn out that the new subgroup to a greater extent leads to serious illness and the risk of hospitalization.
– We know very little about it so far, because it is so early. We hope that data from Denmark will be able to tell us more about this, and we at FHI will also investigate the first cases in more detail in the lab to become wiser.
– Even more mutated
In FHI’s weekly report for week 52, you can read the following about the new subgroup:
“BA.2 is still uncommon, but may appear to have an increasing trend, but is still at a very low level with only around 400 cases sequenced globally, but the majority of these are from Denmark recently.”
Now the number is even higher.
As of 10 January, 1361 BA.2 cases have been sequenced in Denmark. By far the most in the world so far, says Bragstad.
The subgroup is referred to as «an even more mutated version of omicron than BA.1», with «many of the same key mutations as BA. 1 », it is further stated – including 21 common mutations in the spike protein, which to a large extent are linked to the virus’ infectivity.
The omikron variant has in a short time become dominant in Norway.
– That dominance has increased greatly in recent times. There is very little delta virus left. We had a delta variant called AY.4.2 – a virus that has been circulating in Trøndelag. They had a concern about it in the UK, because it increased sharply in several regions just before the omicron came. But after taking omikron took over, it is of much less importance.
So far, both BA.1 and BA.2 are considered omicron, and the pandemic management and perception of the variant’s properties are currently unchanged, Bragstad emphasizes.
– But we must monitor what makes it more contagious if it also wants to spread in Norway.