The shift reflects the spread of the omicron variant.
As the COVID-19 pandemic has swept the globe, more than 5.3 million people have died from the disease worldwide, including over 816,000 Americans, according to real-time data compiled by Johns Hopkins University's Center for Systems Science and Engineering.
About 61.7% of the population in the United States is fully vaccinated against COVID-19, according to data from the Centers for Disease Control and Prevention.
The University of Virginia is pulling out of the Wasabi Fenway Bowl at Boston's Fenway Park due to "the number of COVID cases impacting its roster," the Wasabi Fenway Bowl said.
The game was set to take place on Wednesday between UVA and Southern Methodist University. Tickets will be refunded.
Israeli Prime Minister Naftali Bennett is isolating at home after his daughter tested positive for COVID-19, his office said.
Bennett tested negative via an antigen test Sunday morning as he headed into his cabinet meeting, his office said. When he learned about his daughter, Bennett left the meeting.
Bennett will take a PCR test and stay isolated at home, away from his daughter, until he gets his results, his office said.
Bennett, 49, and his wife have four children.
New South Wales recorded a record 6,394 new coronavirus cases in Christmas Day, according to health officials.
“We would expect that pretty well everybody in New South Wales at some point will get omicron,” Brad Hazzard, state health minister, said during a press conference on Sunday.
Australia's most populous state reported 32,728 new cases in the last week, marking a 172% increase from the 12,013 reported the week prior, according to public health data.
"We're all going to get omicron," Hazzard said. "If we're all going to get omicron, the best way to face it is when we all have full vaccination, including our booster."
Hazzard said he expects everyone in Australia to get omicron, but said health officials have seen "far milder" symptoms with omicron than with other COVID-19 variants.
"Please just think carefully before you, one, call an ambulance, or, two, ask to go to a hospital, or, three, go to hospital, because it may not be necessary," Hazzard said.
Four of the five major U.S. airlines are reporting impacts from omicron.
American Airlines said Saturday that it canceled some Christmas Day flights due to "a number of COVID-related sick calls."
Delta said Friday that omicron and weather contributed to cancellations. Up to 200 of 3,004 Christmas Day flights may be canceled, Delta said.
JetBlue also reported "a number of" canceled flights due to sick calls from omicron.
"Additional flight cancellations and other delays remain a possibility as we see more Omicron community spread," JetBlue said.
United also said some flights were canceled because of omicron.
-ABC News' Mina Kaji
