Mumbai: Omicron detected in 89 per cent samples in new genome sequencing report

A woman gets a dose of vaccine at Nair hospital. Of the 280 patients tested, 174 had taken both doses. Pic/Ashish Raje

Amid speculation over which variant is raging in Mumbai currently, it is now clear that Omicron has taken over the Delta variant, as per the reports of the latest genome sequencing batch. Of the 280 samples which were studied, the genome sequencing lab in Mumbai found that 89 per cent of samples were infected with Omicron. In the previous batch of samples sent for genome sequencing, around 55 per cent was Omicron.

According to BMC's Public Health Department, 373 samples were tested at the Kasturba lab, of which 280 were from Mumbai. Of these 280 samples, 248 or 89 per cent samples were found to be infected with Omicron while 21 or 8 per cent were of Delta derivatives and the remaining 11 or 3 per cent were other subtypes. Of these 11 samples, two were sub-type Delta variants.

All the 13 samples collected from children aged below 18 years were found infected with the Omicron variant. Of the 13 samples, two are in the age group of 0 to 5 years, four are in the age group of 6 to 12 years and seven were in the age group of 13 to 18 years.

"All of these specimens were found to be infected with Omicron. However, these patients did not show any serious symptoms," said an official from the BMC.

Vaccination analysis

Of all 280 patients whose samples were collected, 99 had not taken any dose of vaccine and 76 of them had to be hospitalised. Twelve patients needed oxygen and five patients had to be admitted to the intensive care unit. In terms of single vaccination, there were seven patients of whom six had to be hospitalised.

Out of 174 patients who took both doses of vaccine, 89 had to be hospitalised. Of these, two patients needed oxygen, while 15 patients had to be admitted to the intensive care unit.

Genome sequencing has been carried out regularly since August 2021. The result of the previous round on 31 December, 2021 showed that 55 per cent samples were infected with the new variant. Of the 282 samples, 156 or 55 per cent were Omicron, 89 patients or 32 per cent were Delta derivatives and the remaining 37 or 13 per cent were Delta variants.

How Omicron replaced Delta

. August 2021: 68 per cent samples were Delta, 13 per cent Kappa
. September 2021: 81 per cent Delta
. October 2021: 88 per cent Delta variants and derivatives
. November 2021: 99 per cent Delta variant and derivatives
. December 2021: 99 per cent delta variants and derivatives
. December 15, 2021: 97 per cent Delta variants and derivatives, 2 per cent Omicron
. December 31, 2021: 55 per cent Omicron, 45 per cent Delta derivatives and variants
. January 2022: 89 per cent Omicron, 8 per cent Delta derivatives

Age group analysis of 280 samples

. 8 per cent or 22 patients are in the age group of 0 to 20 years
. 34 per cent or 96 patients are in the age group of 21 to 40 years
. 28 per cent or 79 patients in the age group of 41 to 60 years
. 25 per cent or 69 patients are in the age group of 61 to 80 years
. 5 per cent or 14 patients are in the age group of 81 to 100 years