TOPSHOT - US President Joe Biden speaks about the status of the country's fight against Covid-19 and the Omicron variant, in the State Dining Room of the White House in Washington, DC, on December 21, 2021. - Biden on Tuesday sought to reassure Americans about the country's ability to battle the rapidly spreading Omicron variant, now the dominant coronavirus strain in the United States, saying the nation was "prepared." (Photo by Brendan SMIALOWSKI / AFP)