16 NBMCH Covid-19 samples identified 'variant of concern'

SANKHA GHOSH, SNS, SILIGUR1, 21 JULY 2022: Sixteen Covid samples that had tested positive for Covid-19 in the virus research and diagnostic laboratory (VRDL) of the North Bengal Medical College Hospital (NBMCH) in Siliguri have been identified as the variant of concern (VoC).The reports were based on 27 samples that had been sent to the National Institute of Biomedical Genomics (NIBG) at Kalyani for genome sequencing in June, sources said.

Sources at the NBMCH said that of the 27 samples, 16 were found to be VoC.

"According to the data, 16 samples were VoC, and six were found to be the BA.2-sub variant of omicron. Among the rest, three were BA.2.10, five were BA.2.38, and two were BA.2.73. The samples had been sent to the NIBG on 20 June. The variants are sublineages of omicron, the variant that had fueled India's third Covid- 19 wave during January this year. The other samples do not come under the VoC," a source said. According to experts, it was, however, unclear whether those variants were contributing to the current surge in daily infections. They said BA.2--an omicron sublineage—had dominated the coronavirus cases in the county by the second half of February, and BA.2.10, the sub-variant of omicron, was among the sub-variants that had triggered the spike in Covid cases in some places like Delhi and Telangana in April-May, the BA.2.38 has been re-classified and established that it leads to milder disease, just like its parent sub-variant BA1.Genome sequencing is carried out to ascertain what variant of the novel coronavirus has infected a person. The NIBG is the only institute in Bengal that conducts the genome sequencing of samples. Only samples of people who test positive for Covid- 19 are sent to the institute.

According to NBMCH superintendent Dr Sanjay Mallik, they had received the reports from the NIGB.

"We have received the reports of the Covid samples sent for genome sequencing in lune. We have sent 104 more samples to the NIBG on 14 July, and the reports are awaited," Dr Mallik said.

Virologists have stressed on sustained genome sequencing from recent infections to determine the strains. They said it was important to keep sending the samples for sequencing and look out for clusters of infections, intensive surveillance amid the abated epidemic and the resumption of economic and social activities.

Around 30 tests on an average are con ducted daily in the VRDL at the NBMCH. The laboratory generally caters to Darjeeling district.

"But sometimes, patients from the districts like North Dinajpur, Cooch Behar also undergo Covid tests here, when they meet doctors at the NBMCH," sources said.

Meanwhile, 13 patients were admitted in Covid block II at the NBMCH today. Seven persons who had tested Covid-positive have died at the N BM CI! this month. The

authorities there have said most of them had pre-existing diseases.