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Apart from Delhi (57 cases) and Maharashtra (54 cases), the fast-spreading Omicron strain has seen a rise in Telangana (24), Karnataka (19), Rajasthan (18), Kerala (15) and Gujarat (14).
Three cases have been reported in Jammu and Kashmir and two each in Odisha and Uttar Pradesh. Andhra Pradesh, Chandigarh, Ladakh, Tamil Nadu and West Bengal have reported one case each.
Amid signs of rise in Omicron infections, the Centre, in an advisory, has asked the states to activate "war rooms" and bring back curbs, including night curfews to contain it. It also listed a series of prevention and containment measures that included extensive testing and regulation of gatherings.
The letter from the health ministry called for "greater foresight, data analysis, dynamic decision making and strict and prompt containment action", as it directed the states/union territories to be "prompt and focused and take containment measures and restrictions even before these thresholds are reached".
Besides Omicron, the Delta variant is "still present" in different parts of the country, the letter read.
India's coronavirus tally reached 3,47,58,481 today after the country reported 6,317 new infections, which is a jump of 18 per cent from yesterday's 5,326 cases. The active cases have declined to 78,190, the lowest in 575 days.
With 318 deaths over the past 24 hours, the total death count in the pandemic has climbed to 4.78 lakhs.
The Omicron strain of Covid, known to be highly transmissible, has set off alarm bells and stoked grim memories of the devastating second wave of the pandemic that had brought the country's health infrastructure on its knees.
In US, the new variant accounts for 73 per cent of all sequenced Covid cases, surging from around 3 per cent last week, according to the latest federal estimates.
The World Health Organization has said the Omicron variant is spreading faster than the Delta variant and is causing infections in people already vaccinated or who have recovered from Covid.
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