A report published on Friday by the U.K. Health Security Agency found that people who were infected with the omicron variant had a reduced risk of requiring hospitalization, as compared to people who were infected with the delta variant.

The risk of hospital admissions among those with omicron was about half of that for delta, researchers found.

Individuals who had a booster dose were also found to have a "substantial reduction" in the risk of hospitalization, compared to those who are unvaccinated.

Researchers noted that these lower risks do not necessarily correlate to a reduced hospital burden during a COVID-19 surge, particularly given the higher growth rate and immune evasion seen with omicron.

Preliminary analyses also estimated a lower risk of hospitalization among omicron cases in school-aged children 5 to 17 years old, compared to delta cases in the same age group.

-ABC News' Arielle Mitropoulos

Rep. Ayanna Pressley, D-Mass., is the latest lawmaker to test positive for COVID-19. Pressley announced the news Friday afternoon, saying she was experiencing "relatively mild " symptoms and isolating.

She also took the opportunity to say she was vaccinated and boosted and advocate for others to do the same.

"Vaccines save lives," she said in a statement. "With this unprecedented pandemic continuing to rage, I am deeply grateful for the scientists, researchers, and frontline healthcare workers who have worked tirelessly to develop vaccines that are safe and effective, and ensure that our communities are protected."

Pressley, who has garnered national attention as a member of "The Squad" alongside Reps. Alexandria Ocasio-Cortez, Rashida Tlaib and Ilhan Omar, is one of more than a dozen members of Congress to test positive in the past two weeks. Illinois Rep. Chuy Garcia announced Thursday that he had also tested positive for a breakthrough case and was experiencing mild symptoms.

The total number of confirmed COVID-19 cases continues to surge in New York. The state is reporting more than 76,000 positive cases over the last 24 hours, marking another single-day record for the state.

"We're breaking records every day," Gov. Kathy Hochul said Friday at a COVID-19 briefing.

Meanwhile, nearly 8,000 New Yorkers were in the hospital with the virus on Thursday, an increase of more than 500 from the previous day.

Hochul announced that students in the State University of New York and City University of New York systems will need to receive their booster shot by Jan. 15, or whenever they are eligible for the extra shot. The requirement affects roughly 2.3 million students across the state.

The governor also said she is extending the mandate that businesses require either masks or vaccines, by two weeks, to Feb. 1.

Hochul pushed the importance of vaccines, especially for 5 to 11-year-olds, only 28% of whom have received their first dose, according to Hochul.

"We are not going to leave any stone unturned in terms of finding out how we can get parents to do the right thing for their children," she said.

In a piece of encouraging news, the number of hospitals in the state with less than 10% capacity has dropped from 35 to 21, according to Hochul, who signed an executive order in November that required hospitals with such limited capacity to pause non-essential surgeries.

-ABC News' Will McDuffie

Texas Gov. Greg Abbott has requested resources for federally-supported COVID-19 testing locations, medical personnel, as well as additional federal allocations of monoclonal antibodies.

"Detecting COVID-19 and preventing COVID-related hospitalizations are critical to our fight against this virus," Abbott said in a press release Friday.

Texas has seen more than 104,000 confirmed COVID cases in the past week, with a 22.30% testing positivity rate, according to Johns Hopkins University's Coronaivrus Research Center. The center also reports that the state has a 58.45% vaccination rate.

Dr. Anthony Fauci strongly recommended against large New Year's Eve parties at Wednesday's White House briefing.

"Should you change or cancel your plans? If your plans are to go to a 40-50 person New Year's Eve party with all the bells and whistles and everybody hugging and kissing and wishing each other a happy new year, I would strongly recommend that this year, we do not do that," Fauci said.

Fauci said "all indications point to a lesser severity of omicron versus delta." But he warned, "we should not become complacent since our hospital system could still be stressed in certain areas."

White House COVID-19 coordinator Jeff Zients said, "We have directly helped more than 30 states and territories by deploying over 2,100 federal personnel and thousands of ambulances, ventilators and other critical supplies."

Supplies include gloves, masks, respirators and face shields, he said.

He added, "More than 13,000 National Guard members have been activated in 48 states to support the COVID response, from vaccinations, to testing, to clinical care."

At the briefing, CDC Director Rochelle Walensky defended the agency's shortened isolation guidelines.

"We do know the vast majority of viral transmission happens in those first five days, somewhere in the 85 to 90% range. So if a person can isolate for the first five days they absolutely should," she said. "We also don't know that antigen tests give a good indication of transmissibility at this stage of infection. On the other hand, we know that after five days people are much less likely to transmit the virus and that masking further reduces that risk. And this is why people need to mask for five days after the five days of isolation."

After five days, asymptomatic people with COVID-19 can leave isolation, but must wear masks around others, according to the new guidelines.

-ABC News' Cheyenne Haslett