• Dr. Anthony Fauci predicted that the latest wave of the coronavirus pandemic may hit its peak in the U.S. by the end of January.
• "It's tough to say," said Fauci, President Joe Biden's top medical advisor, when asked on CNBC's "Closing Bell" when the surge in infections fueled by omicron variant will start to recede.
• "I would imagine, given the size of our country and the diversity of vaccination versus not vaccination, that it likely will be more than a couple of weeks, probably by the end of January, I would think," Fauci said.

Dr. Anthony Fauci on Wednesday predicted that the latest wave of the coronavirus pandemic may hit its peak in the U.S. by the end of January.

"It's tough to say," said Fauci, President Joe Biden's top medical advisor, when asked on CNBC's "Closing Bell" at what point the current surge in infections, fueled by the omicron variant, will start to recede.

"It certainly peaked pretty quickly in South Africa," where the highly transmissible new variant was identified last month, Fauci said. "It went up almost vertically and turned around very quickly."

"I would imagine, given the size of our country and the diversity of vaccination versus not vaccination, that it likely will be more than a couple of weeks, probably by the end of January, I would think," Fauci said.

Fauci also said it is technically possible that omicron could hasten the end of the pandemic, if it proves true that that variant, with its high degree of transmissibility, replaces other strains of the virus that cause more severe infections.

"I would hope that's the case," Fauci said when asked about that possibility, but "there's no guarantee that that would happen."

But "if you have a very transmissible virus that replaces another virus, and [the replacement virus] has less of a degree of severity, that would be a positive outcome," he said.

"But you can never guarantee," he stressed. "This virus has fooled us before. Remember we thought with the vaccines everything was going to be fine, and along came delta, which threw a monkey wrench into everything."

Then came omicron, Fauci noted, which has fueled a massive spike in cases around the world — including in the U.S., where a record-high number of Covid infections have been reported this week.

Still, experts have been "pleased to see" that recent data from numerous countries show omicron infections are less severe than those from delta, Fauci said.

"What you say is possible, that that would happen, but there's no guarantee that that would mean the end of a serious outbreak," Fauci said.

"I hope that's what's being foreshown now, right? That we're going to be seeing that," he added. "Hope so, but can't guarantee it."