Corona variant found in India to be called 'Delta' in new WHO system
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Science & Technology
3rd Jun, 2021
The World Health Organisation (WHO) has recommended a set of names to label emerging coronavirus variants that are deemed to be of global concern.
About the new system of labeling
- The variant which was first identified in India and technically known as B.1.617.2, can now be described as 'Delta'.
- A sublineage of the B.1.617 family is B.1.617.1 that was identified in India and now bears the popular label 'Kappa.'
- The 'UK variant' as 'Alpha'.
- The existing scientific nomenclature system will continue.
- Purpose: The new names would only be to aid public discussion using labels that were "non stigmatising" to the countries where they were first identified.
- So far, four Variants of Concern(VOC) have been identified by the WHO: B.1.1.7, B.1.351, P2 and B.1.617.2. and association of country’s name was stigmatising the pandemic.
About the B-1617 variant
- First in India: The B-1617 variant of coronavirus was identified in India.
- Dispersal: This variant is able to spread more easily than earlier forms of the virus.
- Mutation: It carries a mutation called L452R that affects the virus’s spike protein.
- The L452R mutation changes the part of the spike protein which directly interacts with ACE2.
- The ACE2 molecule is found on the surface of our cells that the virus binds with to get inside.
- It is estimated to be around 20% more transmissible than the earlier form of the coronavirus.
- Vaccine inefficiency: The vast majority of vaccines are based on targeting the spike protein.
- The protein is on the outer surface of the virus and its change makes every time hard for the immune system to detect it.
- Their public labels will be Alpha, Beta, Gamma and Delta respectively, after the first four letters of the Greek alphabet.
- It will be easier and more practical to discussed by non-scientific audiences.
Classification of Variants
In collaboration with a SARS-CoV-2 Interagency Group (SIG), the CDC established 3 classifications for the SARS-CoV-2 variants:
Variant of Interest (VOI)
- It is a variant with specific genetic markers that have been associated with changes to receptor binding, reduced neutralization by antibodies generated against previous infection or vaccination, reduced efficacy of treatments, potential diagnostic impact, or predicted increase in transmissibility or disease severity.
Variant of Concern (VOC)
- A variant for which there is evidence of an increase in transmissibility, more severe disease (e.g., increased hospitalizations or deaths), significant reduction in neutralization by antibodies generated during previous infection or vaccination, reduced effectiveness of treatments or vaccines, or diagnostic detection failures.
- These variants spread more easily and quickly than other variants, which leads to more cases of COVID-19.
Variant of High Consequence (VOHC)
- A variant of high consequence has clear evidence that prevention measures or medical countermeasures (MCMs) have significantly reduced effectiveness relative to previously circulating variants.