The US just hit a record average of daily new Covid-19 cases

The US hit a seven-day average of 265,427 new Covid-19 cases on Tuesday, blowing past the country's previous record of about 252,000 daily cases, reported nearly a year ago on January 11.

The new peak, according to Johns Hopkins University data, comes amid a rapid acceleration of infections in the United States -- and across the world -- since last month.

And experts predict the Omicron variant -- the most contagious strain of coronavirus yet -- is going to make the start of 2022 very difficult.

"January is going to be a really, really hard month. And people should just brace themselves for a month where lots of people are going to get infected," said Dr. Ashish Jha, dean of the Brown University School of Public Health.

And the US could "see half a million cases a day -- easy -- sometime over the next week to 10 days," CNN medical analyst Dr. Jonathan Reiner said Sunday.

Most people who are vaccinated and boosted won't get severe illness, but that won't be true for the unvaccinated, Jha said.