COVID-19 updates: Elizabeth Warren tests positive

The senator says she's experiencing "mild symptoms."

Last Updated: December 20, 2021, 12:51 AM EST

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.

Latest headlines:

Here's how the news is developing. All times Eastern.
Dec 17, 2021, 11:57 AM EST

UK reports highest daily cases ever

The United Kingdom reported 93,045 new cases in the last 24 hours, breaking a daily record for the third day in a row.

A large eletronic board at Waterloo station urging people to get boosted as the government accelerates it's Covid-19 booster program to get all adults vaccinated before the end of the year to stop the rapid rise in cases in London, Dec. 17, 2021.
Amer Ghazzal/Shutterstock

PHOTO: A steady stream of patients arrives at The Royal London Hospital in Whitechapel, London, Dec. 16, 2021.
A steady stream of patients arrives at The Royal London Hospital in Whitechapel, London, Dec. 16, 2021. The Omnicron variant has seen the largest number of infections in a single day on December 15th. The number has risen again on December 16th to the highest ever since the pandemic started.
Mark Thomas/Shutterstock

The total number of cases over the last week now stands at 477,229, a 38.6% increase from the previous week.

-ABC News' Guy Davies

Dec 17, 2021, 11:39 AM EST

Rockettes canceled due to breakthrough cases

Friday's four Radio City Rockettes shows have been canceled due to breakthrough COVID-19 cases in the New York City production.

Radio City Rockettes perform at the 89th Annual Rockefeller Center Christmas Tree Lighting Pre-Tape at Rockefeller Center on Nov. 30, 2021 in New York City.
James Devaney/GC Images

Plans for future shows haven't been determined. 

-ABC News' Aaron Katersky

Dec 17, 2021, 11:35 AM EST

CDC studies find schools can test kids rather than quarantine 

The Centers for Disease Control and Prevention on Friday endorsed a practice in schools called “test-to-stay,” which allows unvaccinated kids and staff to test instead of quarantine after being exposed to COVID-19.

The CDC says the practice can be employed in addition to other mitigation measures, such as vaccination and at least 3-feet of physical distance among students wearing masks.

The new guidance follows two studies out of Los Angeles County, California, and Lake County, Illinois. Both studies found no significant transmission in school when test-to-stay was used.

The studies were conducted before the omicron variant was detected in the U.S.

-ABC News' Anne Flaherty

Dec 17, 2021, 11:01 AM EST

Hospitals stretched thin in Wisconsin, Michigan

In Wisconsin, only 4% of ICU beds are available.

"This is getting really scary," Dr. Jamie Hess, an emergency physician at the University of Wisconsin, told ABC News.

"We're really reaching a crisis point where we have more patients to take care of then we have beds in the hospital or staff to care for them," Hess said.

Michigan has been struggling through a similar surge for nearly three months, with the state reporting more than 6,500 new cases each day. On average, more than 500 patients are being admitted to hospitals each day.

"Where we are right now feels a lot like the first surge back in March of 2020," Erin Dicks, a nurse manager at MICU Henry Ford Hospital, told ABC News. "We don't have enough beds to be able to manage this."

Dicks said so many patients are young.

"I think one of the biggest frustrating pieces for my staff is that they look at this as, this is preventable -- people don't have to die here," Dicks said.

-ABC News' Arielle Mitropoulos