A study by the scientists of Hyderabad-based CSIR-Centre for Cellular and Molecular Biology (CCMB) has said a few novel variants of coronavirus are spreading more in some states in the country and a closer surveillance is needed. It further stated that the mutants worrying many countries globally have been identified with only a low prevalence in India so far, but hastened to add it might be simply because not enough sequencing has been done.
The CCMB scientists have been at the forefront of sequencing and analyzing the genome of the coronavirus SARS- CoV-2in the country. A comprehensive analysis of coronavirus variants in the country and their evolution during the pandemic by the scientists presented in a recent publication suggested new types would keep emerging due to natural process of mutation and the best way to control the potential damage by their spread is through extensive genome surveillance, a release from CCMB said.
"We now have emerging evidence that N440K (variant) is spreading a lot more in southern states. Closer surveillance is needed to understand its spread properly, CCMB Director Rakesh Mishra said in the release. Accurate and timely detection of new variants that may show greater infectivity or worse clinical symptoms, including "immune escape", will be extremely important to pre-empt disastrous consequences, he said.
While vaccines are helpful, the "social vaccine" of masks, hand-hygiene and physical distance is the most effective weapon against the pandemic, the study said. The scientists presented their findings of analysis of over 5,000 coronavirus variants and how they have evolved over the course of the pandemic.
"The take home of this comprehensive work is that due to the natural process of mutation, variants will keep emerging.The best way to control the potential damage is to exercise extensive genome surveillance and take measures to prevent the spread of new variants as and when detected," it said.
The novel variants that are worrying many countries globally have been identified with only a low prevalence in India so far and they include the "variants with immune-escape E484K mutation and the N501Y mutation with higher transmission rate," Mishra said. "However, their apparent low prevalence might be simply because not enough sequencing has been done. More coronavirus genomes need to be sequenced across the country to accurately identify the emergence of these and other new variants, Mishra, the corresponding author of the study, said.
In the paper, the authors explain how different coronavirus variants gained prevalence in the country during the last one year. The release said the recently discovered variants in many countries have raised concerns because of their mutations in the spike protein that makes the coat of the virus and come in contact with the human cells.
The spike protein is required for binding to the receptors on human cells. Mutations in this protein can help the virus in some cases. It can increase the viral transmission rates by enhancing its affinity to human receptors, it said.
Some of these coronavirus variants can also be immune- escape and cause reinfection, it said, adding "Our immune systems cannot identify them from previous infections because of the changes in their protein structures." The paper documents the Spike mutation landscape of SARS-CoV-2, showcasing the ones that have emerged with high prevalence in the country and abroad, the release said.
(with inputs from PTI)