Omicron- a new variant

• IAS NEXT, Lucknow
• 30, Nov 2021

Reference News:

The new variant B 1.1. 529, which was designated as a 'Variant of Concern' by World Health Organisation has been assigned the name Omicron.

• Reported by public health officials of South Africa, the new variant has triggered a lot of concern worldwide over a probable resurgence of Covid infections.

How different it is from the original virus?

The B1.1.529 has more than 2 times the number of bad spike mutations than the Delta variant. The new variant has an extremely high 32 worrisome mutations in the spike protein, which is a real concern than the Delta variant.

The WHO currently lists 5 variants of concern:

1. Omicron (B.1.1.529), identified in southern Africa in November 2021.
2. Delta (B.1.617.2) which emerged in India in late 2020 and spread around the world.
3. Gamma (P.1), which emerged in Brazil in late 2020.
4. Beta (B.1.351), which emerged in South Africa in early 2020.
5. Alpha (B.1.1.7), which merged in Britain in late 2020.

VARIANTS OF INTEREST– There are currently two:

1. Mu (B.1.621), which emerged in Colombia in early 2021.
2. Lambda (C.37), which emerged in Peru in late 2020.

Variant of Interest (VOI) and Variant of Concern (VOC):

A SARS-CoV-2 VOI is a SARS-CoV-2 variant:

1. with genetic changes that are predicted or known to affect virus characteristics such as transmissibility, disease severity, immune escape, diagnostic or therapeutic escape; AND
2. that has been identified as causing significant community transmission or multiple COVID-19 clusters, in multiple countries with increasing relative prevalence alongside increasing number of cases over time, or other apparent epidemiological impacts to suggest an emerging risk to global public health.

 A SARS-CoV-2 VOC is a SARS-CoV-2 variant that meets the definition of a VOI and, through a comparative assessment, has been demonstrated to be associated with one or more of the following changes at a degree of global public health significance:

1. increase in transmissibility or detrimental change in COVID-19 epidemiology; OR
2. increase in virulence or change in clinical disease presentation; OR
3. decrease in effectiveness of public health and social measures or available diagnostics, vaccines, therapeutics.

How do variants of a virus emerge and why?

• Variants of a virus have one or more mutations that differentiate it from the other variants that are in circulation.
• Essentially, the goal of the virus is to reach a stage where it can cohabitate with humans because it needs a host to survive.
• Errors in the viral RNA are called mutations, and viruses with these mutations are called variants. Variants could differ by a single or many mutations.