Anthony Fauci, director of the US' National Institute of Allergy and Infectious Diseases said that over a dozen of passengers have contracted the dangerous infection.
"Forty of them have gotten infected. They are not going to go anywhere. They're going to be in hospitals in Japan", Fauci said, cited by CBS News.
He added that people with symptoms would also not be able to get on the evacuation plane. Others, he went on, are set to be evacuated "starting imminently" to Air Force bases in the US.
If any of the evacuees starts developing symptoms on board the plane, they will be segregated, according to the health official. All the evacuees will be placed under 14-day quarantine upon the arrival in the US.
According to the US embassy in Japan, the US government has chartered flights that were expected to depart from Yokohama to the United States on Sunday.
"These charter flights are the only opportunity for eligible passengers to fly to the United States until March 4, 2020, at the earliest. This date is 14 days after the remaining passengers are expected to depart the ship on February 19," the statement said.
The cruise liner Diamond Princess got quarantined after a passenger tested positive for the new coronavirus. Over 3,700 passengers and crew members, including some 400 US nationals, have been placed under mandatory quarantine until 19 February. Several countries now aim to evacuate their nationals as the number of those infected on board keeps rising. According to the latest data, 355 people got infected on board the ship.