WATCH: Biden says we might get back to normal by next Christmas

"Y'know all the experts, all the committee that I have put together, the leading researchers in the world, in the United States on this committee of mine, headed up by Dr. Fauci and others, they tell me be careful not to predict things that you don't know for certain what's gonna happen because then you'll be held accountable," Biden responded.

"I get that. I think based on all that I've learned and all that I've studied and all that I think that I know, it's fairly, it's a high probability, that the vaccinations that are available today and the new one, Johnson & Johnson, God willing, will prove to be useful. That with those vaccinations, the ability to continue to spread the disease is gonna diminish considerably because of what they call 'herd immunity.'

"And now they're saying somewhere around 70 percent of the people need to, some people say around 50, so a significant number have to be in a position where they are, they have been vaccinated, and or they've been through it—"

"Antibodies," Cooper interrupted, filling in Biden's thought.

"Have antibodies. And so if that works that way, as my mother would say with the grade of God and the good will of the neighbors, that by next Christmas I think we'll be in a very different circumstance, God willing, than we are today.

"I think a year from now, when it's 22 below zero here. A year from now I think there'll be significantly fewer people having to be socially distanced, have to wear mask, etcetera, we don't know.

"So I don't want to over promise anything here. I told you when I ran, and when I got elected, I would always level with you," he said.

He said "we don't know for certain but it is highly unlikely that by the beginning of next year's traditional school year in September we are not significantly better off than we are today."

Then he told everyone to wear masks, socially distance, and wash your hands with warm water.