Omicron sub-lineage variant under investigation by U.K.

LONDON/COPENHAGEN, Jan 21 (Reuters) - The UK Health Security Agency on Friday designated a sub-lineage of the dominant and highly transmissible Omicron coronavirus variant as a variant under investigation, saying it could have a growth advantage.

BA.2, which does not have the specific mutation seen with Omicron that can help to easily distinguish it from Delta, is being investigated but has not been designated a variant of concern.

"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," Dr Meera Chand, incident director at the UKHSA, said.

"Our continued genomic surveillance allows us to detect them and assess whether they are significant."

Britain has sequenced 426cases of the BA.2 sub-lineage, and the UKHSA said that while there was uncertainty around the significance of the changes to the viral genome, early analysis suggested an increased growth rate compared to the original Omicron lineage, BA.1.

UKHSA said that 40 countries had reported BA.2 sequences, with the most samples reported in Denmark, followed by India, Britain, Sweden and Singapore. ...