What is 'Stealth Omicron', the Covid-19 sub-variant causing a surge in Asia and Europe

A sub-variant of the Omicron strain is driving a surge in the number of Covid-19 cases in Asian and European countries.

In South Korea, over 6 lakh cases were reported on Thursday while in China the sub-variant called ‘Stealth Omicron’ has led to the country’s worst Covid-19 outbreak in 2 years.

A UK based-study recently reported that ‘Stealth Omicron’ remains at a high level even as coronavirus infections decline across England.

According to the latest report of US Centres for Disease Control and Prevention, the sub-variant is responsible for one-fourth of the new Covid-19 infections in the country.

This particular sub-variant of Omicron has been dubbed ‘Stealth Omicron’ because it is difficult to detect. While presence of certain mutations in sub-variant BA.1 made it possible for the virus to the detected in RT-PCR tests, Stealth Omicron or BA.2 misses these mutations in its spike protein thus making it difficult to detect.

Though BA.2 shares over 30 mutations with that of BA.1, it also has 28 unique mutations

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The World Health Organisation has said that the sub-variant is as severe as its parent. Just like Omicron it affects only the upper respiratory tract and does not affect the lungs.

Dizziness, extreme fatigue, fever, coughing, sore throat and cold are some of most common symptoms of ‘Stealth Omicron’