COVID tracking data only from big cities, not all-inclusive, say experts

Pune: Over 90 per cent of the COVID-positive samples representing the circulating variants in India and currently taken up for genome sequencing are primarily only from the big city areas, experts attached to the sequencing and research laboratories in the country said.

Owing to the drastic decline in testing and COVID positivity rate over the last many months, genome sequencing of COVID-positive samples drawn from international travellers and the community (infected patients) to rule out the presence of newer variants, has remained largely focused on big cities despite the general agreement on the need for genomic research in diverse populations, experts TOI spoke to have underlined.

The experts are of the view that genomic research needs collaborative work across all urban and rural areas to rule out the community spread of extremely contagious variants.

“Stepping up the RT-PCR testing in small pockets and drawing a fine mix of positive samples from diverse (urban-rural) areas for tracking variants will only bolster the surveillance that the Centre has reintroduced in the wake of the sudden spurt in cases in countries such as Japan, the US, Korea, Brazil and China.

Small districts such as Amaravati and Akola in Maharashtra were the first to report the Delta variant of COVID in India in December 2020. The variant had eventually led to widespread COVID cases across the country during the second wave of the pandemic.

“The laboratories doing genomic sequencing in India under the INSACOG network would earlier get positive samples from the urban and rural parts, as COVID cases were seen across the demographics and geographics. The drastic decline in cases led to a sharp fall in genome sequencing work across the country. Genome sequencing is currently limited to a small chunk of samples, in which over 90per cent of samples are from some bigger cities,” a senior INSACOG scientist said on Friday.

A senior scientist from Pune-based ICMR-National Institute of Virology (NIV), one of the key research hubs in western India, said, “We have got only eight positive samples for genome sequencing so far this month (December). They were mainly from city areas."

When contacted, experts working on the project at AIIMS, Raipur (Chattisgarh), IGIMS, Patna (Bihar), and Government Medical College in Panjim (Goa) also corroborated the trend. India on Friday reported 185 new coronavirus infections, while the active cases declined to 3,402.