New Omicron variant spreads faster but boosters remain effective

Just as Australia begins to see a stabilisation in Omicron cases, a new sub-variant could blow the lid open to a wave of infection.

As most Australian states and territories detect a “very low number” of the new Omicron variant, there are fears it could be more contagious than the original.

Dubbed the ‘son of Omicron’, health authorities in the US and UK believe the variant has the ability to spread more rapidly in households.

The UK Health Security Agency said on Friday the rate of transmission among household contacts was 13.4 per cent compared with 10.3 per cent for the original Omicron.

But despite the increased transmissibility, initial research indicates the booster doses are just as effective against the new sub-variant strain with vaccines blocking 13 per cent of cases — a rate that rose to 70 per cent two weeks after a booster, according to Bloomberg.

Cases of the new Omicron variant has been detected around the world. Picture: Ulet Ifansasti/Getty Images

“We now know that BA. 2 has an increased growth rate which can be seen in all regions in England,” Susan Hopkins, the UK Health Security Agency’s chief medical adviser, said in a statement.

Tom Peacock, a virologist at Imperial College, London, tweeted that the latest variant should not call into question the effectiveness of existing vaccines.

“Several countries are near, or even past the peak of BA. 1 waves. I would be very surprised if BA. 2 caused a second wave at this point,” he said. “Even with slightly higher transmissibility this absolutely is not a Delta-Omicron change and instead is likely to be slower and more subtle.”

The BA. 2 sub-variant has raised concerns over its contagiousness and has been detected in more than 40 countries, though currently it is most prevalent in Europe. It now accounts for almost half of all Covid-19 cases in Denmark, for example, where it has overtaken the original Omicron variant.

Initial research suggests the new variant may be more contagious. Picture: Stephane de Sakutin/AFP

In Australia, three cases have been detected in NSW and one case in Queensland. An ACT health spokesperson said it had also seen a “small number of cases” of sub-variant BA. 2 but the predominant type circulating in the community was still Omicron BA.1.

Germany’s Health Minister Karl Lauterbach fears the new sub-variant may delay the peak of the Omicron wave slightly.

Around the world, BA. 2 — the new Omicron variant — has been called “Omicron’s sister”, “Omicron’s brother” and “Omicron’s son”.

The ‘son of Omicron’ could delay the peak of cases in places such as Germany. Picture: Daniel Leal/AFP

“They call it the ‘son of Omicron’, but it’s more of a cousin – it’s a variant related to Omicron,” Melbourne University clinical epidemiologist Nancy Baxter told Today on Thursday.

“It is spreading. We are particularly seeing it in Denmark. We don’t know if it’s going to be a problem yet.”

BA. 2 has yet to be designated a variant of concern by the World Health Organisation but scientists are interested in understanding whether it is different to the original Omicron strain when it comes to contagiousness and severity.