1/ U.S. Covid-19 cases hit their highest level of the pandemic. The U.S. reported 441,278 new Covid-19 cases Tuesday – the highest single-day total – and surpassing the previous daily record by nearly 150,000. The seven-day average of U.S. cases topped 267,000 – more than double the rate in early December – exceeding the previous high mark of about 252,000 average daily cases set on Jan. 11, 2021. Hospitalizations and deaths, meanwhile, have been rising, but remain far below peak levels. The CDC reported that Omicron accounted for 58.6% of all Covid-19 cases in the U.S., while the Delta variant accounted for 41.1% of cases. (Politico / New York Times / NBC News / CNBC / Bloomberg)

2/ The CDC defended its decision to shorten the recommended isolation from 10 to five days for asymptomatic individuals who test positive for Covid-19, saying “we must adapt” as the coronavirus has also “proven its ability to adapt quickly.” The agency said the change in guidance was “motivated by science demonstrating that the majority of SARS-CoV-2 transmission occurs early in the course of illness.” CDC Director Rochelle Walensky, however, acknowledged that minimizing disruptions to the economy in part motivated the decision, saying it “really had a lot to do with what we thought people would be able to tolerate […] that people were willing to adhere to.” As part of the updated guidance, the CDC did not recommend that people test negative for Covid-19 before reentering society, which public health experts and union leaders have criticized as reckless because it relies on people’s self-judgment to assess their transmission risk – which could lead to more spread and more Covid-19 cases. Instead, the CDC recommended that those ending their isolation can go back to their regular activities as long as they wear a mask for an additional five days. (Politico / NBC News / New York Times / Washington Post / Associated Press / NPR / NBC News)

3/ Biden conceded that his efforts to expand Covid-19 testing capacity is “not enough. It’s clearly not enough,” adding that the long testing lines over the Christmas weekend “shows that we have more work to do.” The Biden administration, however, announced plans to order 500 million at-home test kits, which officials expect the free tests to be available as early as January. During a meeting between state leaders and members of his Covid-19 response team, Biden added: “I wish I had thought about ordering a half a billion [tests] two months ago,” before the recent surge. The FDA, meanwhile, said preliminary research shows some rapid antigen tests may be less ...