Omicron sub-variant BA.2 appears capable of causing severe illness, says new study

A recent lab study suggested that the BA.2 subvariant of the Omicron coronavirus variant may possess certain features that not only make it more transmissible, but also more capable of causing severe disease.
This comes at a time when several countries are lifting measures put in place to contain the Omicron variant as the recent wave of infections driven it appears to be waning.

The study, that is yet to be peer reviewed, was recently posted on the preprint repository BioRxiv.
Contrary to the findings of the study, the World Health Organisation on Thursday noted that while the BA.2 sub-variant is more transmissible than BA.1, there is no difference in severity. “Among all sub-variants, BA.2 is more transmissible than BA.1. However, there is no difference in terms of severity,” Maria Van Kerkhova, COVID-19 Technical Lead at WHO said in a video.

The BA.2 sub-variant of Omicron has spread rapidly in countries including Denmark, Philippines, South Africa and the United Kingdom in the past few weeks. While the sub-variant follows the initial spread of the BA.1 sub-variant of Omicron, it has now started outcompeting BA.1, suggesting more transmissibility, according to researchers.
The study, conducted a team of researchers at the University of Tokyo, found that similar to BA.1, BA.2 subvariant of Omicron appears to largely escape the immunity induced COVID-19 vaccines.

“Neutralisation experiments show that the vaccine-induced humoral immunity fails to function against BA.2 like BA.1,” the authors of the study said.
The study also said that even though BA.2 is considered an Omicron variant, its genomic sequence is much different from BA.1, suggesting that the virological characterics of BA.2 differ from that of BA.1
According to WHO, the BA.2 sub-variant now accounts for roughly one in five new Omicron cases recorded across the world.
(With PTI inputs)