Omicron Becomes Dominant COVID Variant In The US, Accounting For 73% Of New Infections

The highly transmissible Omicron variant is now dominant in the United States, according to new data released by the CDC on Monday. The variant now makes up more than 73% of new infections, a nearly six-fold increase compared to the week before. 

Omicron makes up the highest share of new cases in the South, Central Midwest, Pacific Northwest, and the New York area. 

The steep rise of the Omicron variant comes as cases surge across the country, particularly in New York, which is reporting one in 10 new cases nationally. On Monday, the state reported its highest number of daily infections for the fourth consecutive day, and New York City is now averaging more daily infections since the pandemic began. But hospitalizations both in the city and statewide have yet to near pandemic records. 

The surge of new Omicron cases mirrors trends seen in other countries, including South Africa, Denmark, and the United Kingdom.

According to data from the U.K., the risk of household transmission after an initial Omicron case is nearly three times higher than it is for Delta, and preliminary research indicates it has a higher rate of reinfection as well. In the U.S., Houston Methodist Hospital found that after less than three weeks, Omicron cases accounted for 82% of new symptomatic COVID patients. It took the Delta variant three months to reach that point. 

Recent data released by vaccine manufacturers has confirmed initial fears that mutations to the variant's spike protein could allow it to more easily evade immunity among individuals who are fully vaccinated, but booster doses have been shown to significantly increase antibody levels. Moderna said Monday that a booster dose of its vaccine resulted in a 37-fold increase in antibody levels. 

President Joe Biden is slated to address the country's recent surge and present his administration's plans to mitigate the impact of the Omicron variant in a speech Tuesday. 

First published on December 20, 2021 / 6:59 PM

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