Just as the global population was heaving a huge sigh of relief that the COVID-19 pandemic was in its last legs after having wreaked havoc on health and upended all sense of normalcy for two consecutive years – 2020 and 2021, the World Health Organisation (WHO) declared Omicron as another new variant of concern on November 26, 2021. Having been first detected in the African countries of South Africa and Botswana, omicron has since spread rapidly among people of all ages, in at least 180 different nations worldwide.

Also Read: Omicron: All You Need To Know About The New COVID-19 Variant
Stealth omicron Variant BA.2

Presently, in the period from January to March 2022, coronavirus cases are witnessing a spike in several countries in Asia and Europe such as China, South Korea, United Kingdom, Germany, France, Italy, Netherlands, owing to omicron. While this occurred initially due to the omicron sub-variant BA.1, the infections in the past few weeks are being triggered by yet another sub-variant being dubbed as the “stealth omicron variant” - BA.2. Furthermore, Israel has reported another novel variant that is a combination of the two omicron sub-strains – BA.1 and BA.2.

While COVID-19 cases in India are right now on a decline, with all stringent lockdown measures having been lifted across the country, the Ministry Of Health in the Central Government as well as chief healthcare organizations of the Indian Council Of Medical Research (ICMR) have nevertheless sounded the alarm bells and warned all regions to be cautious. States and union territories all over the Indian subcontinent have been advised to rigorously follow the five-fold strategy to halt the spread of infection. This comprises RT-PCR testing for COVID-19, tracking cases within localities, prompt medical treatment of positive cases, vaccinating every single individual of age 12 and above and adhering to COVID protocol of wearing face masks, using hand sanitisers and maintaining social distancing in public places.

Also Read: The RT-PCR Test: How This Assay Detects COVID-19 And Other Details Explained

In addition, due to the global rise in cases of COVID-19 currently, not only a wave of infections but a ripple of panic as well has been generated, with a lot of misinformation being passed about the sub-variants of omicron. It is hence of utmost importance to separate fact from fiction, reality from rumour in such scenarios and stay abreast of the true scientific information about COVID-19 variants.

What Are The Five Variants Of Concern?

The WHO has declared five variants of concern of COVID-19:

  • Alpha - B.1.1.7 - first identified in the United Kingdom (UK) in the last quarter of 2020
  • Beta - B.1.351 - emerged in South Africa in the final phase of 2020.
  • Gamma - P.1 - initially detected in Brazil towards the end of 2020.
  • Delta - B.1.617.2 - surfaced in India in late 2020 and then spread quickly to many countries around the world
  • Omicron - B.1.1.529 - begun in South Africa in November 2021 and rapidly transmitted to people across the globe

While infections from alpha, beta, gamma, delta have largely reduced globally thanks to rigorous lockdowns and COVID-19 vaccines, omicron is currently still inducing high positivity rates, possessing an elevated transmissibility and the ability to afflict even fully vaccinated persons i.e. breakthrough infections.

What Are The Two Sub-Variants Of Omicron?

Thus far, two sub-variants of omicron have been identified – BA.1 and BA.2. At first, omicron infections presented in the form of BA.1, but currently the resurgence of COVID-19 has been largely attributed to BA.2 – the stealth omicron variant.

While both BA.1 and BA.2 have many similarities in their structure, there are also differences in their genetic sequences arising from amino acid variations in the spike protein and other adjoining protein assemblies.

What Are The Symptoms Of The Stealth Omicron Variant?

The stealth omicron BA.2 does not showcase any new symptoms when compared to signs induced by previous variants of concern. However, the BA.2 sub-strain of omicron initially exhibits indications of dizziness and fatigue – an early sign of coronavirus infection due to omicron.

Other symptoms such as mild fever, scratchy throat, headaches, dry cough, body pain also arise from BA.2 omicron infection.

How Do The Two Sub-Variants Of Omicron Combine?

Israel has reported COVID-19 infections due to a new sub-type of omicron developing from the combination of BA.1 and BA.2. Experts at the WHO have clearly outlined the process of how two sub-variants combine to form a new strain of virus in the body. The mechanism is termed as antigenic drift.

Once the omicron sub-strains BA.1 and BA.2 enter the human body, they undergo a natural process wherein mutations occur during replication. Then, two or more different sub-variants of the virus – in this case BA.1 and BA.2 – combine to form a new sub-type of omicron. Essentially, these two viral sub-strains exchange a lot of genetic information and effectively form a new sub-variant of omicron in the end.

How Severe Is Infection From The Ba.2 Omicron Sub-Variant?

Based on patient analyses and research studies conducted up until now, it has been established that the omicron variant of concerns in both forms of the sub-strains – BA.1 and BA.2 does not seem to affect the lungs and hence, serious symptoms of loss of sense of smell, taste and breathing difficulties do not occur in many positive COVID-19 cases.

However, although Omicron sub-variants BA.1 and BA.2 induce only mild infections, the WHO has still warned all countries to be on the lookout as even already inoculated persons can contract COVID-19. The WHO has advised all nations to ramp up their vaccination drives and administer booster doses as well to fully vaccinated populations, communicating clearly that the pandemic was far from over and that COVID-19 vaccines and boosters would significantly help halt the spread of infection in future.