GLOBAL VARIANT OF CONCERN

GLOBAL VARIANT OF CONCERN

Subject : Science & tech

Context: Recently, the World Health Organization (WHO) has classified a coronavirus variant which was first identified in India as a “global variant of concern”.

Concept:

• The variant called B.1.617 was classified as a variant under investigation (VUI) by authorities in the UK.
• The Indian government said that this variant also called the “double mutant variant” could be linked to a surge in the cases of coronavirus seen in some states.
• The B.1.617 variant of SARS-CoV-2 carries two mutations, E484Q and L452R.
• The two mutations are found in the virus’s spike protein.
• The spike protein helps the virus to bind itself to the human cell’s receptors and gain entry into a host cell.
• The E484Q mutation is similar to E484K, a mutation found in the United Kingdom (lineage B.1.1.7) and South Africa (B.1.351) variants of the coronavirus.
• The L452R mutation has been found in fast spreading variants in California (B.1.427 and B.1.429).
• It can increase the binding power of spike proteins with ACE2 receptors on human cells, making it more transmissible.
• It has already spread to more than 17 countries and several countries have put travel restrictions for passengers coming from India as a result of the surge in cases here.

How does the WHO define a variant of concern?

• The WHO says that a variant of interest (VOI) becomes a variant of concern (VOC) if it has been demonstrated to be associated with increase in transmissibility or detrimental change in COVID-19 epidemiology.
• The increase in virulence or change in clinical disease presentation or a decrease in effectiveness of public health and social measures or available diagnostics, vaccines, therapeutics are also considered.
• A variant may be classified as a VOC by the WHO in consultation with the WHO SARS-CoV-2 Virus Evolution Working Group.