A study conducted by the Institute of Liver and Biliary Sciences has noted the community spread of Omicron in Delhi and a definite shift from the predominance of Delta to the new variant in the capital.
The study also observed that young adults and males were infected more in comparison to children and the elderly which could be due to more socialising and close connections than other groups, according to the IANS which reported the study’s findings on Saturday.
The study is based on epidemiological, clinical and genome sequence analysis of 264 cases since the day Omicron was designated as Variant of Concern (VoC) by the WHO. Respiratory specimens from all RT-PCR confirmed positive cases between November 25 to December 23 were collected from five districts of Delhi and were subjected to whole-genome sequencing. Complete demographic and clinical details were recorded.
In India, it is the first study that provides evidence of Omicron community transmission with significantly increased breakthrough infections, decreased hospitalisation and symptomatic infection rate among individuals with high seropositivity against SARS CoV-2 infections.
Of the 264 cases included during the study period, 68.9 per cent were identified as Delta and its sub-lineages while 31.06 per cent were Omicron with BA.1 as the predominant sub-lineage (73.1 per cent).
Most Omicron cases were asymptomatic (nP,61 per cent) and did not require any hospitalisations. A total of 72 (87.8 per cent) cases were fully vaccinated.
At least 39.1 per cent had a history of travel or contact with Omicron patients while 60.9 per cent showed community transmission. A steep increase in the daily progression of Omicron cases with its preponderance in the community was observed from 1.8 per cent to 54 per cent, the study highlighted.
The results also suggest a large reduction in protection against the Omicron variant as 87.8 per cent population got reinfected after full primary vaccination thus implying increased breakthrough infections. The results suggest a large decrease in protection from the vaccine or natural immunity against COVID infections caused by the Omicron variant.