NEW DELHI: Even as the double-mutant Indian variant of SARS-CoV-2 virus is wreaking havoc across the country, genome experts have flagged another lineage of the coronavirus, named B.1.618, with major immune escape capacity. This variant is said to be driving the pandemic in West Bengal and spreading very fast.
Based on the sequences of B.1.618 submitted by Bengal-based National Institute of Biomedical Genomics (NIBMG ), the experts say it is characterised by a distinct set of genetic variants including E484K, a major immune-escape variant that can escape monoclonal antibodies and panels of convalescent plasma.
While initial sequences of the B.1.618 lineage have been found in West Bengal, the members of this lineage is also found in other parts of the world but do not have the full complement of the variants as found in India.
Genome sequencing shows that proportions of B.1.618 have been growing significantly in recent months in West Bengal, and along with B.1.617, it forms a major lineage of the deadly virus in the state.
On whether the lineage is more infectious, experts say there are many unknowns for this lineage at this moment, including its capability to cause re-infections as well as vaccine-breakthrough infections, and additional experimental data is required to assess the efficacy of vaccines against this variant.
The current surge in Covid-19 cases in the country is attributed to the double mutant version of the virus.
The double mutant (L452R + E484Q) was announced by the National Centre for Disease Control (NCDC) on March 25 after it was identified in samples of saliva taken from people in Maharashtra, Delhi, and Punjab.
The variant has a particularly increased prevalence in Maharashtra, where the strain has been present at a very low frequency since October 2020.
WATCH:
Genome study says...
Proportions of B.1.618 have been growing significantly in recent months in Bengal, and along with B.1.617, it forms a major lineage of the deadly virus in the state