The omicron variant now makes up a majority of COVID-19 cases in the United States, at 73.2 percent, the Centers for Disease Control and Prevention said in updated figures released on Monday.
The statistics are for the week ending Dec. 18 and show the rapid spread of the variant in the U.S. That spike is a significant increase from just 12.6 percent of cases one week earlier.
The omicron variant is highly transmissible, and officials are bracing for a large wave of infections in the coming weeks. However, people who are vaccinated, and especially those with booster shots, are well protected against severe disease from the variant, experts say, meaning the greatest risk is for the unvaccinated.
President Biden will give a speech on Tuesday to update the nation on his plans for fighting the variant.
The White House has emphasized that given the widespread availability of vaccines and booster shots there is no need to have business closures and lockdowns like there were last year.