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Vaccines and masks are important, the government said in a cautionary note Friday. "WHO is warning against the decline in mask usage. The global scene of Omicron is disturbing... We are now operating at a risky level," said Dr VK Paul, who heads the centre's Covid task force.
In Maharashtra, a three-year-old was among seven new patients confirmed by the state government on Friday; Mumbai has banned large gatherings for two days amid scare. All fresh cases in the state are either asymptomatic or have mild symptoms. A majority of cases in India are also mild.
More than 90 international passengers who returned to India since December 1 tested positive for Covid. At least 80 of them returned from "at-risk countries".
The second Omicron patient in Delhi had also visited South Africa, one of the "at-risk" nations. At the national capital's LNJP hospital, samples of 27 passengers have been sent for genome sequencing so far.
Fifty-nine countries have logged Omicron cases so far, the centre said on Friday, adding that five states in India have seen patients affected by the new variant.
The UK, Denmark, and South Africa are the top three countries with the highest number of Omicron cases, the government warned.
Top US scientist Anthony Fauci earlier this week clarified that Omicron was not worse than prior strains, and was possibly milder.
The new variant is "clearly highly transmissible," very likely more so than Delta, the current dominant global strain, Dr Fauci said, adding that "there is some suggestion that it might even be less severe".
Urging countries for quick yet measured action, the World Health Organization earlier this week said the new variant may change the course of the pandemic. "We can prevent omicron becoming a global crisis. We can prevent omicron from becoming a global crisis."
The new variant has also sparked a fresh debate about booster doses. Pfizer and BioNTech SE said initial lab studies show a third dose of their Covid-19 vaccine may be needed.
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