The Omicron surge of coronavirus cases had not yet peaked in the US and the country is expected to see an increase in hospitalisations and deaths in the next few weeks, Surgeon General Dr. Vivek Murthy has warned.
In an interview on CNN's "State of the Union," Dr Murthy noted the "good news" of the plateaus and drops in known cases in the Northeast, especially in New York City and New Jersey.
But "the challenge is that the entire country is not moving at the same pace", he said, adding "we shouldn't expect a national peak in the coming days".
"The next few weeks will be tough," he said.
The highly contagious Omicron variant has fueled an explosive surge of known cases, with an average of more than 800,000 new cases a day reported on Saturday, according to a New York Times database.
The next several weeks would overwhelm hospitals and staff, Dr. Ashish Jha, dean of the Brown University School of Public Health, was quoted as saying.
"Right now we're at about 150,000 people in the hospital with Covid," he said on "Fox News Sunday." "That's more than we've ever had. I expect those numbers to get substantially higher."
In Kansas City, Omicron has overwhelmed hospitals since the holiday season, the city's mayor, Quentin Lucas, said in an interview on CBS's "Face the Nation."
"We have seen incredible challenges in our health care network, even getting employees that are working in our EMS services, fire department and in public safety,a Lucas said. "It is a substantial concern."