Nagpur: The recently published genomic surveillance report by the National Environmental Engineering Research Institute (Neeri) has found 12 new variants of Omicron lineage in samples from Vidarbha districts — including Nagpur — and Tamil Nadu.
Omicron sub-lineage XBB has been detected in four samples and XBB.1 in one sample. The study led by scientist Krishna Khairnar studied 88 samples submitted to the lab between September 12 and October 8 from the two regions.
Over 850 Covid-positive samples were processed for the study. However, 60 from Tamil Nadu and 28 from Vidarbha districts qualified for the 30th series of whole genome sequencing at Neeri.
Officials said though 12 new variants have surfaced, BA.2.75.2 continues to be dominant despite its falling percentage-wise share. The variant is now at 22.7%. The sub-lineage BA.2.75.2 had grown to 85% in September after starting to replace the BA.2 early this year. Among the newly identified variants, BM.1.1 has emerged as the dominant strain with 11 samples testing positive for it out of the 88. It has evoked similar interest among the surveillance authorities as XBB variant.
Among asymptomatic cases, BM.1.1 is at over 13%, which calls for a close monitoring of the variant. Officials said though Covid cases are at an all-time low and not causing much hospitalisation, the emergence of new variants must be taken seriously.
The XBB variant too is more infectious thus far and has been behind the surge in parts of South Asia, especially Singapore and Hong Kong.
The Neeri lab has completed genome study of 2,349 Covid-positive samples for January 1 to October 13.
Distribution of Omicron lineage
BL.1 | 1.1% (1/88)
BL.2 | 2.27% (2/88)
BL.3 | 1.1% (1/88)
BL.4 | 1.1% (1/88)
BM.1.1 | 12.5% (11/88)
BM.4.1.1 | 2.27% (2/88)
BN.1 | 2.27% (2/88)
BN.2 | 1.1% (1/88)
BR.1 | 1.1% (1/88)
BY.1 | 3.4% (3/88)
XBB | 4.5% (4/88)
XBB.1 | 1.1% (1/88)