Coronavirus updates: 1st vaccines now on the way to all 50 US states

Navajo Nation begins a three-week emergency lockdown on Monday, during which residents are required to remain at home 24 hours a day, seven days a week.

Essential businesses, including grocery stores, gas stations, laundromats, hay vendors and restaurants providing drive-thru or curbside service, may remain open on weekdays between 7 a.m. and 7 p.m. Off-reservation travel is not permitted and on weekends, a full lockdown will be in place.

"The Navajo Nation’s health care system is in a state of major crisis," Myron Lizer, vice president of Navajo Nation, said in a statement. "We cannot be careless and we have to stay the course."

The rules include exceptions for essential workers and emergency situations. Residents are permitted to leave their homes for essential food, medicine and supplies, as well as outside exercise within the vicinity of their homes and wood gathering.

The lockdown rules will be in effect until Dec. 28.

On Monday, Dr. Anthony Fauci painted a grim future for the United States if Americans don't adhere to public health measures during the holidays. "Without substantial mitigation, the middle of January can be a really dark time for us," Fauci said during a news conference held by New York Gov. Andrew Cuomo.

Americans need to keep social distancing until 75% to 80% of the population can get the COVID-19 vaccine, which would provide an umbrella of community-level protection, Fauci explained. "By the time you get to the beginning of April, you’ll start getting people who have no high priority, just the normal man and woman, New Yorker in the street who's well, has no underlying conditions [getting the vaccine]," he added.

As of Monday, New York State's testing positivity rate was 4.7%, according to Cuomo. The governor estimated that more than 70% of infections spreading in the state were connected to small gatherings.

-ABC News' Rachel Katz contributed to this report.

For the first time since the start of the coronavirus pandemic, the United States is reporting an average of nearly 2,200 deaths from the disease per day, according to an ABC News analysis of data collected and published by The COVID Tracking Project.

The national seven-day average of COVID-19 deaths per day day is currently 2,171. That figure has increased by 139% in the past month.

Last week, there were nearly 15,000 fatalities from the disease recorded nationwide, including five days where the daily death toll surpassed the 2,000 mark. That's roughly equivalent to 88 COVID-19 deaths reported each hour.

Meanwhile, the U.S. has reported over 100,000 new cases of COVID-19 every day for more than a month straight, including three consecutive days where the daily count topped 200,000.

Just in the last month, the national seven-day average of daily new cases has doubled, now averaging 191,736 -- the highest it has been since the beginning of the pandemic.

There were 1,018,657 cases recorded nationwide in the first five days of December. To put that in perspective, it took nearly 100 days from the first recorded COVID-19 case in the U.S. for the country to surpass 1 million confirmed cases.

Hospitalizations continue to surge to unprecedented levels, with over 101,000 patients currently hopitalized with COVID-19 across the country -- a new national record.

In the past two months, current hospitalizations have more than tripled, increasing by 223%.

ABC News' Benjamin Bell, Brian Hartman, Kim Soorin and Arielle Mitropoulos contributed to this report.

South African Health Minister Zweli Mkhize has called on final-year students who attended end-of-year parties to immediately self-quarantine for 10 days to prevent spreading the novel coronavirus.

Mkhize made the plea to students and parents on Sunday, after numerous people who recently attended "Rage" parties in Ballito and Jeffrey's Bay tested positive for COVID-19. The events are hosted every year in South Africa as thousands of students celebrate the end of matriculation.

"We confirm that we have now identified a number of COVID-19 confirmed cases arising from these super-spreader events," Mkhize said in a statement. "This therefore means that if you attended any of these Rage events, you are now regarded as a contact."

In addition to quarantining, Mkhize also urged attendees to get tested as soon as possible.

South Africa has the highest tally of COVID-19 infections in all of Africa, with more than 814,000 confirmed cases including over 22,000 deaths.