With input from Dr Monica Vasudev

1567: UK identifies over 77 cases of B.1.617 variant first reported in India

It is suspected that the mutation of B.1.617 strain has made the variant spread faster and partially evade immunity.

It is believed that the current variant is mainly responsible for India’s current second Covid-19 wave, with an alarming rise on the infection rates and hospital admissions.

E484Q, L452R

The B.1.617 strain has two spike mutations, E484Q and L452R. These mutations are also reported in several other coronavirus variants, however the two have been reported together for the first time in India.

E484Q mutation

The E484Q mutation is similar to E484K, a mutation found in the British (lineage B.1.1.7) and South African (B.1.351) variants of the coronavirus.  

L452R mutation

The L452R mutation has been found in rapidly spreading variants in California (B.1.427 and B.1.429). It enhances the binding of the spike protein with ACE2 receptors on human cells, increasing its transmissibility. L452R can also increase viral replication.

When the two strains, E484Q and L452R are present together, they are more infectious, and can evade antibodies. While these two strains together, spread faster, are more infectious, they are also less virulent and doesn’t lead to dramatic hospital admissions.

Dr Sujeet Singh, director of the National Centre for Disease Control (NCDC) said, “the central government had reported in March that 15-20 per cent samples in Maharashtra had this variant; on the basis of the latest sequencing data we know that this number is now over 60 per cent.”

Dr KK Aggarwal

President CMAAO, HCFI and Past National President IMA