people recovering from covid. it now says five days of isolation is enough, as long as a person has no symptoms and continues to wear a mask for the next five days. the top infectious disease expert in the u.s., dr. anthony fauci, says he expects covid cases will continue to surge, but he's dismissing the need for a vaccine mandate for air travel, at least for now. >> right now, i don't think people should expect that we're going to have a requirement in domestic flights for people to be vaccinated. when i was asked that question, i gave an honest answer. it's on the table and we consider it, but that doesn't mean it's going to happen. i doubt if we're going to see something like that in the reasonably foreseeable future. >> well, more than 2,800 flights worldwide were canceled monday, according to tracking websight flightaware. and with covid cases surging, the travel chaos is threatening to extend through the new year. cnn's richard quest has the latest.