As many as 9,672 Omicron samples were found in January in genome sequencing constituting 75 per cent of the total sequenced samples of COVID-19, a huge rise from the December figure of 1,292, the government said on Thursday.
Addressing a press conference, NCDC Director Dr S K Singh said sub-lineages of Omicron – BA.1 and BA.2 were found in sequenced samples while BA.3 has not been found yet.
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"We were getting more samples of BA.1 earlier mostly found in travellers but now we are seeing that BA.2 has become more prevalent in the community,” Singh said.
He further said that a huge rise from December has been seen in the number of Omicron samples in January.
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"In genome sequencing, a huge increase in Omicron samples was seen between December and January,” he said.
In December, only 1,292 omicron samples while 17,272 samples were of Delta variant and of AY series of COVID-19 in genomic sequencing.
In January, 9,672 omicron samples were found which was about 75 per cent of total sequenced samples and AY lineage was found in 3,201 samples and Delta was found in 1,578 samples, he said.
He further said that Delta variant has been found predominantly in Odisha, West Bengal and Maharashtra.
"It is not that everywhere we are finding only Omicron cases, we are also seeing Delta variant cases which shows that Delta variant impact has not completely ended. In severity and hospitalisation, we can also find delta so it is important we don’t look at hospitalised cases unilaterally that it is omicron so it would be mild,” he said.
Earlier this week, the Indian SARS-COV-2 Genomics Consortia INSACOG said that Omicron is in community transmission stage in India and has become dominant in multiple metros, where new cases have been rising exponentially, with BA.2 lineage, an infectious sub-variant of Omicron, found in a substantial fraction in the country.