The White House's chief medical adviser, Dr. Anthony Fauci, recommended Monday that Americans cancel their plans to go out for New Year's Eve because of the risk that the Omicron coronavirus variant will spread at parties.

"I would stay away from that," Fauci told CNN's "New Day" when asked about the year-end parties many people will attend.

He stated that small gatherings with vaccinated family members or close friends would be safe, but larger, mixed gatherings with people you may not know could pose a risk.

"I have been telling people consistently that if you're vaccinated and boosted and you have a family setting, in the home with family and relatives," it's OK to gather, Fauci explained. "But when you're talking about a New Year's Eve party, we have 30, 40, 50 people celebrating, you do not know the status of their vaccination, I would recommend strongly stay away from that this year."

Dr. Anthony Fauci says he recommends that people "stay away" from large New Year\u2019s Eve gatherings where they don\u2019t know the vaccination status of guests.\n\n"There will be other years to do that, but not this year," he says.\nhttps://cnn.it/3pviwmP\u00a0pic.twitter.com/5eaEpVfWhd

— New Day (@New Day) 1640613078

Fauci's comments come as states with some of the strictest restrictions to reduce the spread of COVID-19 are seeing daily cases spike to levels higher than last winter's pandemic peak.

The New York Times reported that Delaware, Hawaii, Massachusetts, New Jersey, New York, and Puerto Rico are among the areas that have reported more coronavirus cases in the past week than in any other seven-day period. On Friday, the seven-day national average of new daily cases surpassed 197,000, a 65% increase over the last two weeks, data shows.

Hospitalizations and deaths have increased as well, but not nearly as much as positive virus cases. There were about 71,000 COVID-19 hospitalizations reported Friday, an increase of about 8% over previous weeks but substantially below previous peaks. Deaths increased by 3% over the past 14 days, to a seven-day average of 1,345 nationally.

Fauci predicted that the U.S. will continue to see cases surge because of the Omicron variant but suggested they may soon fall as they did in South Africa.

“We're certainly going to continue to see a surge for a while, Kaitlan. I fully expect that it will turn around. I hope it turns around as sharply as what we've seen in South Africa,” Fauci told CNN's Kaitlan Collins.

He acknowledged that the Omicron variant appears to cause less severe disease, but warned that high cases can still put a strain on health care infrastructure.

“It looks like the degree of severity of the disease is considerably less than they experienced with Delta. We’re seeing inklings of that now in the United States. The U.K. is also seeing that. So I do hope that we do have the net effect is a diminution in the degree of severity,” Fauci said.

“But the sheer volume of cases that we're seeing now — yesterday we had 214,000 cases. Even with a diminution in severity, we still could have a surge on hospitals, particularly among the unvaccinated, which we’re really worried about," he continued, adding it's "possible" but unlikely that the U.S. could see 500,000 new cases in a single day.

He emphasized the importance of vaccination and booster shots to protect against severe illness.

“There are so many things that we can do to mitigate against that. The thing we keep talking about is that, you know, if you're not vaccinated, get vaccinated. But importantly, boosters are really looming as something very, very important,” Fauci said.

“Boosters are always good for any variant, but particularly for Omicron. If you are vaccinated and not yet boosted and your time comes for getting boosted, please get boosted. It's going to make all the difference to prevent you from getting severe disease," he added.