The senator says she's experiencing "mild symptoms."
As the COVID-19 pandemic has swept the globe, more than 5.3 million people have died from the disease worldwide, including over 806,000 Americans, according to real-time data compiled by Johns Hopkins University's Center for Systems Science and Engineering.
About 61.4% of the population in the United States is fully vaccinated against COVID-19, according to data from the Centers for Disease Control and Prevention.
George Washington University is joining Princeton, Cornell and NYU by canceling all events and moving exams online.
George Washington officials said there's "a significant increase" in cases, and while people are not severely sick, "it is critical that we act to limit the further spread."
-ABC News' Michelle Stoddart
Boston's historic baseball stadium Fenway Park, which transformed into a mass vaccination site last winter, is expected to reopen its doors as a booster shot location in January, Red Sox officials told ABC News.
The Red Sox are working with the city and the governor's office to finalize the plans, Red Sox spokeswoman Zineb Curran said.
-ABC News' Arielle Mitropoulos
Asked how worried Americans should be about omicron and a post-holiday surge, Dr. Anthony Fauci said that if we didn't have vaccines, boosters and masks he'd "really be worried."
"But we have tools. So get vaccinated, get boosted," Fauci said at Wednesday's White House COVID-19 briefing.
CDC Director Rochelle Walensky said the agency expects to see omicron continue to grow.
"What does this mean for individuals and families as we head into the winter months? A time when families may be gathering with one another over the holidays? It means that it is vital for everyone to get vaccinated and boosted if they are eligible," Walensky said.
White House COVID-19 response coordinator Jeff Zients added, "We're not going to shut down our economy in any way. We're going to keep our schools and our businesses open."
-ABC News' Cheyenne Haslett
The United Kingdom confirmed 78,610 COVID-19 cases in the last 24 hours -- the highest daily number since the start of the pandemic, officials said Wednesday.
Prime Minister Boris Johnson encouraged everyone to continue to get vaccinated and boosted. He said 650,000 boosters were administered Tuesday and now 45% of all adults have received a booster.
-ABC News' Joe Simonetti
