The government on Wednesday said the UK variant – known to have higher transmissibility and potential to cause severe Covid disease – is declining in proportion across the country.
But while the incidence of the UK variant seemed to be declining, the double mutant variant B.1.617 – found in Maharashtra – could be a cause of the current surge seen over the last one and half months, said Sujeet Singh, director, National Centre for Disease Control (NCDC), the key agency steering surveillance and matching sequencing of samples of SARS-CoV2 and clinical evidence.
The double mutant Covid variant that was first detected in India, has spread to at least 17 countries, the World Health Organisation (WHO) has said.
“The B117 lineage of SARS-CoV2 (UK variant) because of which we saw increased number of cases in Maharashtra and Delhi, is declining…The B.1.617 lineage has been seen in Maharashtra and now being seen in many places. The current surge in cases over the last one and half months in some states show a co-relation with the rise in the B.1.617 lineage of SARS-CoV2,” Singh said.
Singh, however, said epidemiological or clinical co-relation of the B.1.617 variant is yet to be established completely. Renu Swarup, secretary, department of Biotechnology, said while sentinel genome surveillance and genome sequencing for SARs-CoV2 began in India in April 2020, variants of concern emerge only when co-relation between molecular surveillance and epidemiological incidence is established with substantial data.
She said the reports were regularly shared with the states in February and March when the variants were being studied.
“Genomic surveillance is important but genomic sequencing in isolation does not give us any indication unless and until it is co-related with clinical or epidemiological data and that whole cycle is completed for us to get that information on variant to know whether it is a variant of interest, variant of concern or just not important for us and it’s a routine mutation,” she said.
