Emergence of newer variants of SARS-CoV-2 and what it means for India

The emerging SARS-CoV-2 variant, AY.1 or B.1.617.2.1 or commonly known as the Delta plus, harbors a non-synonymous mutation at 417th (K417N) amino acid position in the spike protein as previously observed in Beta and Gamma variant (these variants are characterized as being highly infectious and may reduce the potency of vaccines). The convergence of K417N mutation is believed to aid the virus to escape the existing approved treatment regimes. According to a database maintained by CSIR-IGIB, the mutation was associated with resistance to a newly developed monoclonal antibody treatment drug (Casirivimab and Imdevimab, for patients with moderate and severe disease, but at a high risk). So far, se

ven out of the 28,065 genomes sequenced in India belong to AY.1 variant. Globally, the number varies among different countries depending on the number of genomes sequenced. The reported country-wise figures for the AY.1 variant are; UK (45), Switzerland (23), Portugal (21) etc. It is depressing to see the lower numbers of genomes sequenced in India (28,065) as compared to 466,437 in UK and 549,164 in the US.

Due to the relatively limited evidence linking specifically AY.1 to large outbreaks and significant disease transmission, the variant hasn't still made up to the 'variants of concern' list of WHO. Early reports say that the AY.1 variant is diverging to two sub-lineages, one particular cluster has been found in California, and a larger cluster comprises of sequences from eight other countries including Nepal, India and UK. Needless to say, the current lower prevalence of the variant shouldn't be a reason to let our guards down as 31% of the total reported cases in India are caused by the Delta variant and, provided the fact that we still clearly don't know the underlying reasons for the drastic population dynamics of the variants, we have all the more reason to worry about an impending third wave.

On the flip side, we are now clearly seeing the insufficiency of genome sequencing analysis in India, as its the gold standard to know the evolutionary dynamics of the virus. Last but not the least, if India reported 7 cases of AY.1 variant out of 28,065 genomes sequenced so far, just imagine how many more would be there roughly if we could leverage more resources to sequence at the pace of US and UK.

A point to ponder!