The CDC said the US had "entered a phase of high-level transmission" of the virus.
On Friday the US recorded over 2,500 deaths and nearly 225,000 new cases.
It has confirmed 14.3 million cases and more than 278,000 deaths.
Mr Biden - who is due to take office on 20 January - also said he expected his inauguration to be a scaled-back event without large crowds because of coronavirus concerns.
"My guess is there'll still be a platform ceremony but I don't know how it's all going to work out," he said.
More about: US Biden coronavirus
