Omicron variant found in NCR, likely to have caused spike in Covid cases

BA.2.12.1 is a variant of the virus's Omicron strain and was found in 60% of total samples tested in Delhi

A new mutant variant of the Sars-CoV-2 virus, which causes Covid-19, has been detected in the National Capital Region (NCR), according to official sources. BA.2.12.1 was found in 60 per cent of the total samples tested in Delhi.

The Union Health Ministry did not confirm the development on Thursday. Majority of the samples sequenced from Delhi in the first two weeks of April have shown presence of BA.2.12 variant, an Omicron sub-lineage. An Indian Sars-CoV-2 Genomics Consortium (INSACOG) source claimed that BA.2.12.1 has been found in some of the samples that were sequenced in Delhi.

Sources also claimed that the variant may be behind the recent surge in cases in the NCR, as this is considered to be highly transmissive and capable of causing re-infections.

"New sub-variants BA.2.12 (52 percent samples) and BA.2.10 (11 percent samples) are showing high transmission and have been found in over 60 per cent of the total samples from Delhi sequenced recently," said an official source.

"The BA.2.12 variant appears to have a growth advantage of about 30 percent to 90 percent per week over BA.2 (Omicron)," the source said.

Over 300 samples have been genome sequenced in Delhi in the first fortnight. The official said the same sub-variants more or less have been found in samples sequenced in neighbouring districts in Uttar Pradesh and Haryana.

Media reports said that Sujeet Kumar Singh, director of National Centre for Disease Control (NCDC), has confirmed the detection of the variant in Delhi. Despite several attempts, Singh could not be reached for a comment.

NCDC leads the INSACOG project.

Recently, this sub-lineage, BA.2.12.1 was identified by the US Centers for Disease Control (CDC) along with BA.2.12 (the sub-variant of Omicron’s BA.2).

Cases have been rising in India. According to Union Health Ministry data as of April 21, 2380 fresh Covid19 cases were reported in the last 24-hours.

A Business Standard analysis showed that between April 16 and April 19, 233 districts across India (out of total 727 districts) reported a rise in positivity rate.

The Brihanmumbai Municipal Corporation (BMC) is also writing to a Central institute seeking clarity on the lineage of the sample which the civic body had concluded to be of the XE variant. On April 6, the BMC had said that one sample, of a woman from South Africa, had been found to be infected with the XE variant. Hours later the Union Health Ministry dismissed the claim.

Later, the BMC sent the sequencing data to the National Institute of Biomedical Genomics (NIBMG), and now an analysis shows that the above-mentioned variant is a combination of BA.1 and BA.2. BMC is thus planning to seek advice on the lineage.

Another man from Gujarat, allegedly tested positive for XE, had travelled to Mumbai. None of his contacts have tested positive for XE, though. XE is considered to be more transmissive than the Omicron variant of the Sars-CoV-2 virus.

The Union Health secretary, in a letter to the governments of Maharashtra, Mizoram, Delhi, Haryana and Uttar Pradesh on April 19, said positivity rates is rising. The Union Health Ministry has urged these states to monitor the spread of infection and take prompt actions wherever required.