‘Stealth Omicron’: All you need to know about the new sub-variant

A sub-variant of Omicron has been rapidly spreading in the US, parts of Europe and some parts of Asia.

Dubbed ‘stealth Omicron’ – because it is difficult to detect – expert say it might lead to a fourth wave of COVID-19 pandemic in the country.

The sub-variant – categorised as BA.2 for now – appears to be transmissible than BA.1, the World Health Organization has said, adding that even though there is a spike in sequences in the new sub-variant, global cases of all coronavirus variants have declined.

“BA.2 differs from BA.1 in its genetic sequence, including some amino acid differences in the spike protein and other proteins. Studies have shown that BA.2 has a growth advantage over BA.1. Studies are ongoing to understand the reasons for this growth advantage, but initial data suggest that BA.2 appears inherently more transmissible than BA.1, which currently remains the most common Omicron sub-lineage reported. This difference in transmissibility appears to be much smaller than, for example, the difference between BA.1 and Delta,” WHO said in a statement explaining the differences between Omicron and its sub-variant.

White House Chief Medical Advisor Dr Anthony Fauci has also said the sub-variant may account for around 30 per cent of all new infections in the US. It is currently the most dominant variant in the country as well.

Fauci told ABC news network that vaccines and booster shots will help prevent serious illness, adding that even if the virus is not as severe, it may cause a worrying uptick in cases in the US in the coming months.