More than 1 million new COVID-19 cases were reported in the United States on Monday, according to Johns Hopkins University.

The 1,082,549 new infections were about double last week's record daily cases, according to the university's data. This is likely due to a reporting backlog of cases from holiday testing.

The US recorded 1,688 deaths related to COVID-19 on Monday, below the record high of 4,442, set on Jan. 20, 2021, according to the university's data.

A record 325,000 children tested positive for COVID-19 last week amid the nation's most significant COVID-19 infection surge yet, according to the American Academy of Pediatrics and the Children’s Hospital Association.

Children accounted for about 17.4% of last week's reported COVID-19 cases, down from previous weeks, when children accounted for more than a quarter of all new cases.

A total of nearly 7.9 million children have tested positive for the virus, since the onset of the pandemic.

ABC News' Arielle Mitropoulos

New York's hospitals will be required to report a breakdown of how many COVID-19 patients were admitted due to the coronavirus and how many were admitted for other needs and only discovered they were infected during their stays.

During a COVID-19 briefing on Monday, Gov. Kathy Hochul cited anecdotal reports of as many as 50% of patients at some hospitals testing positive for the virus who were actually admitted for other reasons, such as car accidents.

"I just want to always be honest with New Yorkers about how bad this is," Hochul said. "Yes, the sheer number of people infected are high, but I want to see whether or not the hospitalizations correlate with that."

She continued, "And I'm anticipating to see that at least a certain percentage overall are not being treated for COVID."

Hospitals will begin reporting their breakdowns Tuesday, but it's unclear how soon the data will be publicly available.

-ABC News' Joshua Hoyos and Will McDuffie

U.S. Surgeon General Dr. Vivek Murthy warned that COVID-19 cases and hospitalizations will continue to increase as the omicron variant rapidly spreads across the country.

"The next few weeks are going to be tough for us," he told ABC's "The View" on Monday. "We’re already seeing record levels of cases, and we're seeing hospitalizations starting to tick up. We're seeing some of our hospital systems getting strained at this point."

Information from South Africa and the United Kingdom indicates omicron could be less severe than previous COVID-19 variants, Murthy said.

"We’re still going to see a lot of people get sick and a lot of hospitalizations, but the overall severity may end up being significantly lower," he said.

Murthy said both South Africa and the U.K. "had a very rapid rise, but then they had a very steep fall" in cases

"I'm hoping that that’s what happens here too," he added.

-ABC News' Joanne Rosa

President Joe Biden announced Tuesday afternoon that he was doubling the federal government's purchases of Pfizer's COVID-19 antiviral pill, from 10 million to 20 million treatment courses.

"They’re a gamechanger and have the potential to dramatically alter the impact of COVID-19, the impact it's had on this country and our people,” Biden said.

He also warned that those who remain unvaccinated "will die" during the ongoing omicron surge.

“So there's no excuse, no excuse, for anyone being unvaccinated,” Biden said.

-ABC News' Ben Gittleson