CHENNAI: THE coronavirus, SARS-CoV-2, is still actively evolving and new mutations can affect the vulnerable like people with comorbidities, even though they are fully vaccinated.
This was found by a study carried out by 28 health professionals and epidemiologists from Tamil Nadu, Malaysia, USA and Sweden. The lead author is Dr TS Selvavinayagam, director of Public Health and Preventive Medicine, Tamil Nadu. The study was published in virology journal Wiley.
A statewide investigation of the genomic surveillance of the Omicron B.1.1.529 and its sublineages was conducted between December 2021 and March 2023. The study was to elucidate mutational patterns and genetic interrelationship in the Indian population.
It identified several unique mutations at different time points and found that omicron is highly competent in its mutating potentials, and that it continues to evolve in the general population, likely escaping from natural as well as vaccine-induced immune responses.
“Our findings underscore the need to scale-up surveillance to assess the vaccine’s temporal and geographic effectiveness against precarious variants,” Selvavinayagam said. The message to public is control non-communicable diseases by lifestyle changes and report to health officials, if symptoms appear particularly, if you are vulnerable.
To understand the genomic heterogeneity, a total of 11,526 samples were sequenced and during the study, a total of 10,663 Omicron variants were reported. Researchers subjected 150 high-quality sequences to evolutionary analyses. “We found evidence for omicron evolution as we detected the emergence of sublineages from B.1.1.529. Phylogenetic analyses have revealed six omicron clusters actively circulating in South India,” the study said.
The unique mutations were consistently detected over a period of time in omicron variants leading to immune evasiveness. The study also has some pitfalls. Of the 1,688 variants sequenced, only 150 were taken-up for the evolutionary analysis. However, it concluded that SARA-CoV-2 continues to remain a health concern.
But, Dr Selvavinayagam said the mutated variants were milder.