Omicron sub-variant: what is BA.2 strain, where in UK has it been found - and should we be worried?

The BA.2 strain of the BA.1 Omicron strain has been found in Britain after it was first detected in Europe.

The cases of the new strain remain low, with only 53 discovered in the UK so far.

- Scientists have discovered a new sub-variant of the Omicron strain in the UK

- The variant, named BA.2, was found in Europe before it had been found in Britain

- There have currently only been 53 confirmed cases of the new strain in the country

- The UK Health Security Agency has said that the BA.2 has been classed as a variant under investigation.

- It comes as England prepares to remove all Omicron Plan B measures and revert back to a Plan A guidance approach

What is the BA.2 variant?

The BA.2 variant is a sub-strain of the BA.1 Omicron variant.

The BA.1 strain remains the most prevalent strain in the UK, however scientists have confirmed 53 incidences of the BA.2 strain have been found in the country.

Both BA.1 and BA.2 share similar characteristics - with a few different mutations - meaning they have both been classes as Omicron.

BA.2 was found to have a different S-gene mutation compared to that of BA.1.

When a PCR test is carried out, scientists are able to distinguish between the two because the BA.2 cases will show positive for the S-gene while the BA.1 case will not.

It was first designated as an Omicron variant on 6 December, with scientists confirming that cases of the strain had been discovered in the UK since 10 January.

How dangerous is the BA.2 Omicron strain?

As of yet, there is little known about the variant, although an initial study by Danish experts show the strain so far has no impact on rates of hospitalisation.

However, it is believed that it may be more transmissible than the BA.1 variant, although there is no conclusive evidence of this yet.

It is also not yet known whether the BA.2 variant causes a more severe symptoms of Covid -19.

The UK Health Security Agency (UKHSA) has confirmed the strain has been classed as a variant under investigation.

Dr Meera Chand, incident director of the UKHSA, said: “It is the nature of viruses to evolve and mutate, so it’s to be expected that we will continue to see new variants emerge.”

Tom Peacock, a virologist from the Imperial College of London, said: “BA.2 appears to be the major Omicron lineage in (part of) India and the Philippines and there is evidence it is growing compared to BA.1 in Denmark, the UK and Germany.

“Consistent growth across multiple countries is evidence BA.2 may be some degree more transmissible than BA.1. This is the main reason BA.2 is currently in the news.”

Although, Mr Peacock did say that he did not expect the BA.2 strain to have a “significant” impact on the current wave of Omicron cases.