U.S. passengers on board the Diamond Princess cruise ship, who have chosen to leave, are transported by shuttle bus in Yokohama to Haneda airport to fly back to the United States via chartered evacuation aircraft, in Japan February 17, 2020. Hundreds of passengers were preparing to be evacuated from a cruise ship on Sunday after spending two weeks under quarantine off Japan over the coronavirus, with Americans flying home on chartered evacuation planes early Monday morning. Courtesy of Philip and Gay Courter/via REUTERS

A bus believed to carry the U.S. passengers of the cruise ship Diamond Princess, where dozens of passengers were tested positive for coronavirus, arrives next to an airplane at Haneda airport in Tokyo, Japan, February 17, 2020. Seventy more people were confirmed with the virus on board the Diamond Princess on Sunday, bringing the number of cases from the ship to 355, the most anywhere outside China. REUTERS/Issei Kato

A chartered evacuation aircraft operated by Kalitta Air waits for U.S. passengers who have chosen to leave the Diamond Princess cruise ship, to fly back to the United States, at Haneda airport in Japan February 17, 2020. Two charter flights operated by Kalitta Air carrying a few hundred American passengers from the ship departed from Haneda Airport on Monday morning. Courtesy of Philip and Gay Courter/via REUTERS

A U.S. health official in a protective suit standing in front of a portable bio-containment unit speaks to U.S. passengers who have chosen to leave the Diamond Princess cruise ship, on a chartered evacuation aircraft to fly back to the United States, at Haneda airport in Japan February 17, 2020. Hundreds of passengers were preparing to be evacuated from a cruise ship on Sunday after spending two weeks under quarantine off Japan over the coronavirus, with Americans flying home on chartered evacuation planes early Monday morning. Courtesy of Philip and Gay Courter/via REUTERS

Phil Courter, a U.S. passenger on board the Diamond Princess cruise ship, wears a face mask on a chartered evacuation aircraft to fly back to the United States, at Haneda airport in Japan February 17, 2020. Seventy more people were confirmed with the virus on board the Diamond Princess on Sunday, bringing the number of cases from the ship to 355, the most anywhere outside China. Courtesy of Philip and Gay Courter/via REUTERS

U.S. passengers on board the Diamond Princess cruise ship, who have chosen to leave, are seen in a chartered evacuation aircraft to fly back to the United States, at Haneda airport in Japan February 17, 2020. Two charter flights operated by Kalitta Air carrying a few hundred American passengers from the ship departed from Haneda Airport on Monday morning. Courtesy of Philip and Gay Courter/via REUTERS