The Omicron coronavirus variant has become the most dominant strain in the United States, comprising 73% of new infections over the past week according to data released by the US Centers for Disease Control and Prevention (CDC).
The new estimates, accounting for cases for week ending December 18, underscore how rapidly the new variant has spread across the US after being detected in just 12.6% of positive COVID-19 cases as of December 11.
According to the CDC, Omicron infections are even more prevalent in some parts of the U.S., including the Pacific Northwest, the Great Lakes, the Southeast, several states centered on Texas, and New England, where it makes up 90% of samples.
US President Joe Biden is scheduled to deliver a speech on the COVID-19 situation, though White House press secretary Jen Psaki has already said there are no plans to lock down the country in response to the Omicron surge.
Top US pandemic advisor Anthony Fauci has meanwhile warned of a difficult holiday season as the Omicron variant ushers in a new wave of global infections.
Early reports nevertheless suggest that this newest strain is no more severe than the Delta variant, despite being more infectious and possibly more resistant to vaccines.
Still, hospitals across the US are ramping up operations amid cancellations of sports and entertainment events.