Omicron has high immune escape potential: INSACOG

New Delhi: Citing global data, Indian SARS-COV-2 Genomics Consortia INSACOG has said there is now clear experimental and clinical data supporting the very high immune escape potential of Omicron, which appears to be the major component of its growth advantage over the Delta variant. With Omicron cases going up 11 per cent globally in the last week, the World Health Organisation on Wednesday warned the new Covid-19 variant still poses “very high” risk and could overwhelm healthcare systems.

Paul Kattuman, professor at the Judge Business School at the University of Cambridge, which has developed a Covid-19 India tracker, has said in an email that “it is likely India will see a period of explosive growth in daily cases and that the intense growth phase will be relatively short”.  He said the “new infections will begin to rise in a few days, possibly within this week”, and went on to add it was hard to predict how high the daily cases could go.

Prof. Kattuman and his research team, developers of the India Covid tracker, expect a sharp rise in infection rates across India. The tracker spotlighted six states as a “significant concern” in a December 24 note, with an adjusted growth rate of new cases exceeding five per cent. This expanded to 11 Indian states by December 26, according to the tracker, which corrects for “day of the week effects” and other variations.

The Union health ministry data released at 8 am Wednesday said India saw 9,195 Covid-19 cases in the past 24 hours – the highest single-day jump in daily cases in three weeks -- pushing the total confirmed tally to 34.8 million infections. The data showed the total number of fatalities due to the disease at 480,592.

The country is also gearing up to prevent another massive outbreak even though only 810 cases of the highly-mutated Omicron were identified in 21 states and Union territories so far. Delhi has so far logged the highest number of Omicron cases at 238, followed by Maharashtra at 167 and Gujarat at 97.

Election-bound Punjab also reported its first Omicron case with a 36-year-old man, who came from Spain earlier this month, testing positive for the new variant. The man, who arrived in India on December 4, visited his relatives in Nawanshahr in Punjab. He had tested negative for coronavirus upon his arrival. Later, he tested positive on December 12.

In the last 24 hours, Delhi reported 923 Covid-19 cases -- an 86 per cent jump in cases from Tuesday and the highest since May 30. Delhi’s positivity rate also jumped up to 1.29 per cent. The national capital’s data suggests that the average daily rise of Covid-19 this time is about 20 per cent faster than during the second wave in March-April 2021.

Maharashtra reported 3,900 Covid-19 cases and 20 deaths in the last 24 hours. Of these cases, Mumbai logged 2,510 -- up from 1,377 cases on Tuesday and the highest daily addition since May 8. Among other cities, Bengaluru had 400 cases, Kolkata 540 and Chennai 294 cases.

While Gujarat reported 548 fresh Covid-19 cases, crossing the 500-mark for the first time after more than six-and-a-half months, Karnataka had 566, Telangana 235, Goa 112 and Rajasthan 100-plus cases.

INSACOG, meanwhile, said there is now clear experimental and clinical data supporting the very high immune escape potential of Omicron, but initial estimates show the severity of illness being lower than what was seen in previous outbreaks. In India, appropriate public health measures and investigations are being conducted for surveillance of Omicron, the genomic consortium said, while noting that globally there appears to be significantly reduced ability of vaccines or prior infection to protect against symptomatic infection by the new variant.

In its latest bulletin, INSACOG said: “While Delta continues to be the most prevalent VOC globally, the Omicron variant has completely displaced it in southern Africa and is on track to become the dominant variant in UK and elsewhere.”

The genomic consortium said: “Initial estimates of severity of illness have, however, been lower than seen in previous outbreaks. Whether these initial observations are generalisable to older non-immune subjects is not clear and the threat level is still considered high.”

WHO highlighted that “consistent evidence shows the Omicron variant has a growth advantage over Delta, with a doubling time of two to three days.” It added: “The overall risk related to the new variant of concern Omicron remains very high.”