The less severe Omicron strain replaced the lethal Delta, variant of coronavirus, in Mumbai which had created havoc in the second wave in the country. Experts cautioned that dropping Covid prevention practices could help the surge of Delta again.

On Thursday, all 237 samples tested positive with Omicron variant as was evident from the city’s tenth genome sequencing result. The sixth genome sequencing had been done in the first week of December and found Omicron’s presence in only 2% of samples. This concluded that in around 90 days, the fast-transmissible Omicron variant with better immune escape properties completely replaced Delta.

Dr Jayanthi Shastri, head of BMC’s genomics laboratory at Kasturba Hospital said that Delta had been wiped off in Mumbai. Gene sequencing since December 2021 showed that the proportion of Omicron in the samples increased from 8% in Dec to 100% in March. Dr Vineeta Bal, an immunologist with the Indian Institute of Science Education and Research, Pune said that the displacement was known as Omicron was highly transmissible. But it was not wiped off from the country.

Also, most of the samples that were tested in the tenth genome sequencing survey had Omicron’s sublineage BA2 which was hyper transmissible and worrisome than BA1. Indian doctors said that though the BA2 sub-type has led to a larger wave and more hospitalizations in the UK, in India both BA1 and BA2 infections showed the same symptoms and level of severity.

Dr Samiran Panda of the ICMR said that in the future emergence of Delta wave or a Delta-like wave was unlikely. Though predicting the evolution of viruses was difficult, In India, most of the population had been exposed to the SAR-S2virus and over 90% vaccinated, which had led to enough hybrid immunity and could prevent any huge wave at the moment.

Source: The Times of India