Anthony Fauci, America's top infectious diseases expert, has warned that the US might witness a "surge upon a surge" of new coronavirus cases cases in the weeks after Thanksgiving due to cold weather and travel.

"We don't want to frighten people, but that's just the reality," Xinhua news agency quoted Fauci, Director of the National Institute of Allergy and Infectious Diseases, as saying on Sunday night in an ABC News interview. "Having said that, we have to be careful now because there almost certainly is going to be an uptick because of what has happened with the travel.