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Omicron accounts for 3 percent of US COVID cases

Residents wait in line at a COVID-19 mobile testing site in the Times Square neighborhood of New York, on Dec. 5.Jeenah Moon/Bloomberg

The omicron variant now makes up 3% of all sequenced Covid-19 cases in the U.S., rising from less than 0.1% in early December, health officials said, a sign of the rapid spread of the new coronavirus version.

The highly mutated variant has now been detected in 33 U.S. states, the Centers for Disease Control and Prevention said in an email. While the delta variant remains the dominant strain in the country, accounting for 96% of sequenced cases, omicron’s proportion is expected to increase, agency spokesperson Jasmine Reed said.

Countries around the world are working to respond to the spread of omicron, a variant that appears to have mutations that may allow it to evade the effects of some vaccines. South African researchers said Tuesday that standard courses of vaccines from Pfizer Inc. and BioNTech SE or Johnson & Johnson prevent as much as 70% of Covid hospitalizations and deaths.


Omicron was first identified in South Africa and classified by the World Health Organization as a variant of concern last month. The CDC is working closely with state and local health officials to monitor its spread, Reed said.

“Every day we learn more about the omicron variant, including about how effective our vaccines and treatments will be against omicron and how easily it spreads compared to delta,” Reed said.

Meanwhile, U.S health officials are encouraging all adults to get booster doses as the winter holidays approach. Earlier this month, President Joe Biden called on care providers to expand the availability of Covid vaccines and boosters in a bid to hold off omicron and combat a winter surge of infections.

About 27%, or 54 million, of fully vaccinated adults had received a booster as of Monday, according to the CDC.