New Jersey, Maryland, Missouri, Nebraska, Pennsylvania and Utah all reported omicron cases, while in New York City, officials reached out to a man who tested positive for the variant and had attended an anime conference at a Manhattan convention center last month along with more than 50,000 people.
Five other attendees have also been infected with the coronavirus, though officials were unsure about which variant they had.
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Dr. Rochelle Walensky, the director of the Centers for Disease Control and Prevention, told “NBC Nightly News” there were about 90,000 new cases a day in the U.S. and “right now, 99.9 percent of them still are the delta variant.”
But she said a number of omicron cases had arrived in the country, and it was possible that more could follow.
Although not the case at the moment, Walensky said “it may very well be that omicron is able to out-compete delta,” although the CDC had yet to see “any symptoms that are unique to omicron” and it was “too early to tell in terms of increased severity.”
Omicron cases have now been detected in 38 different countries since it was first discovered in southern Africa late last month, the World Health Organization said Friday. No deaths have been attributed to the new variant, it added.
In Australia, some states have tightened their domestic border controls after a cluster of omicron cases in Sydney grew to 13 and an infection was suspected in the state of Queensland.
Meanwhile, South Korea reported 5,352 new infections and 70 deaths Saturday, its highest number of new daily cases so far. It has also confirmed nine total cases of the omicron variant, according to health authorities.
India also reported its third omicron case, as its total number of Covid-19 infections grew close to 35 million.
There are also fears of an omicron outbreak in Israel, where seven new cases and 27 suspected cases of the new variant were reported Friday.
In Brazil, the mayor of Rio de Janeiro canceled New Year’s Eve celebrations after the country confirmed the first known cases of the variant in South America’s biggest country.
In Africa, Zambia also detected its first cases in three people, the country’s health ministry said Saturday.
Maria Van Kerkhove, the WHO’s technical lead on Covid-19, called on countries to reassess their vaccination programs to ensure their most vulnerable people are becoming vaccinated against the coronavirus to get ahead of the spread of omicron.
“We don’t know how it will unfold. What we are asking countries to do now is to critically assess their situation,” she said during a question-and-answer session livestream on the WHO’s Facebook page Friday.
She added that countries needed to be “aggressive” against early cases to stem the spread of the new variant.
Associated Press and Reuters contributed.