Crew aboard the coronavirus-hit Diamond Princess cruise ship had continued contact with infected passengers even following the government request on Feb. 5 that passengers self-quarantine in their rooms, a Japanese crew member told Kyodo News in a recent phone interview.

"Crew members did not limit their movements and interacted with passengers who had tested positive for the virus. Other than wearing protective face masks, infection prevention measures were left to the crew," said a crew member who asked to remain anonymous, in the first detailed testimony by a personnel of the ship where nearly 700 people became infected.

Although some believe that the virus likely spread via crew members, the health ministry has insisted that there were no problems with the government's handling of the situation.

(Supplied photo shows the inside of the Diamond Princess.)

"We will investigate whether protective measures were sufficient moving forward," one senior ministry official said.

The crew member had stayed in a facility in Saitama Prefecture following their disembarkation from the ship at the end of February, and has not complained of feeling unwell.

The crew member, who requested their age and gender not be revealed, said they were in charge of providing guidance to sick passengers visiting the medical room, and to infected passengers disembarking from the U.S.-operated, British-flagged Diamond Princess.

Other crew members distributed medicine and served meals to passengers in their rooms, and were involved in 24 hour patrols, they said.

Although the ship's operating company instructed all staff to wear masks and wash their hands properly, "without detailed guidance from the (Japanese) government, we had to judge for ourselves how to keep our distance from infected persons and whether it was okay to enter private rooms," they said.

There was no clear distinction between infected and infection-free zones in most areas aboard the ship, with routes taken by infected passengers also used by crew and other passengers.

While the entrance to the restaurant had pieces of paper with the words "contaminated route" and "uncontaminated route" written on them, and part of its passageway was partitioned with a rope, it led to the same place, they said.

(Supplied photo shows the entrace of a restaurant on the Diamond Princess. A notice reads "clean route.")

Health minister Katsunobu Kato, in charge of Japan's quarantine efforts, told a press conference last month that a special team for infection control provided guidance to medical officers and crew and that places with high risk of infection and those without were separated.

But the crew member questioned on what basis the government was claiming that zoning was enforced inside the ship. They also criticized how quarantine officers and others took over from the crew, saying their response was insufficient.

"There were times when they were late attending to people who had fevers or carrying out virus tests," they said, adding that the elderly and those with pre-existing illnesses such as diabetes "should have been able to (disembark) earlier."

The two-week quarantine at Yokohama Port, south of Tokyo, began Feb. 5 after a passenger who disembarked in Hong Kong on Jan. 25 was found to be infected with the new coronavirus, which originated in the Chinese city of Wuhan.

Over half of the roughly 1,000 crew members slept in twin rooms. Although the ship tried to isolate those exhibiting symptoms, there were not enough rooms available to strictly enforce isolations, they said.

Most of the crew had not been tested by around Feb. 14, and some who had high fevers were even left unattended for a few days, they said.