Delhi labs detect new Omicron sub-variant, government yet to confirm

Genome sequencing laboratories in Delhi have detected a variant of the Omicron sub-variant BA.2—whose emergence was first announced the New York health department—which has a 23-27 per cent growth advantage over the original sub-variant.
The samples that tested positive for the new sub-variant (BA.2.12.1) have been sent to the country’s apex Covid-19 genome sequencing consortium, INSACOG, for confirmation, according to officials from Delhi’s health department.
“We have not detected the sub-variant yet. We have known of this sub-variant only for a couple of weeks and it will take some time before we can say whether it is more transmissible or whether it causes different symptoms,” said a senior official from INSACOG.

Another expert, on the condition of anonymity, said that the new variant was unlikely to lead to an increase in hospital admissions. “Even if it spreads faster, it is similar to the Omicron variant that drove the third wave in India. A huge proportion of the people have already been exposed to it. This variant is unlikely to lead to an increase in severe disease and hospitalisations,” the expert said. The expert also pointed to the good vaccination coverage.
Meanwhile in Delhi, the health department is reviewing the metadata of the samples found to have the BA.2.12.1 to see whether the infections were clustered or found in samples from across the city, indicating a wider spread.
The new variant was found after Delhi started sequencing all positive samples with a CT value of 25 or less from April 9 onwards. The CT value is the number of cycles a sample has to be amplified before the virus is detected. The lower the viral load, the higher the CT value. Samples with a CT value of more than 25 cannot be sequenced well.
Delhi was sequencing all such positive samples towards the end of 2021, when there was a lull in cases between the second and the third waves of the pandemic. This was discontinued when the cases started rising in December-end and the beginning of January.