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A port security officer at the Diamond Princess in Yokohama, Japan’s port. Passengers who tested negative for the coronavirus began to leave the cruise ship today.

Eugene Hoshiko/AP

Scientist decries ‘completely chaotic’ conditions on cruise ship Japan quarantined after viral outbreak

A Japanese infectious disease specialist has harshly criticized the way Japan’s government has handled the COVID-19 crisis aboard a luxury cruise ship docked in Yokohama. Conditions on board the Diamond Princess were “violating all infection control principles” and “completely chaotic,” the scientist, Kentaro Iwata of Kobe University, said in a YouTube video posted on Tuesday evening.

His claims are inflaming an already intense debate over Japan’s handling of the crisis. Scientists have also faulted the slow release of epidemiological data about the ship that could help control efforts elsewhere.

Iwata released the 12-minute video (below), along with a version in Japanese, just hours before the official end to a quarantine that has kept some 3700 passengers and crew confined on the ship since 5 February in an effort to limit the entry of the virus into Japan.

In his video, Iwata painted a disturbing picture of conditions on the Diamond Princess. “The cruise ship was completely inadequate in terms of infection control,” he said. There was no distinction between infection-free “green zones” and potentially contaminated “red zones,” Iwata said, and people were coming and going between the zones with and without personal protection equipment, eating lunch and handling smartphones with their protective gloves on. The lack of zone separation extended to the ship’s medical center and even to the medical officer. “She was saying that she was already infected; she was giving up protecting herself.”

Speaking from a Yokohama hotel room where he has confined himself to avoid exposing his family to the virus, Iwata told Science today that he hopes his outspoken video will lead to changes in Japan’s bureaucratic approach to infection prevention. He also said Japan has missed a chance to answer important epidemiological questions about the new virus and the illness it causes. For instance, a rigorous investigation that tested all passengers at the start of the quarantine and followed them through to the end could have provided information on when infections occurred and answered questions about transmission, the course of the illness, and the behavior of the virus. In the absence of such studies, “There is no way to tell [for sure] if secondary infections occurred after the start of the quarantine,” Iwata says.

The crisis began on 2 February when Japanese authorities learned that a man who left the ship in Hong Kong had later fallen ill and tested positive for the virus that causes COVID-19. The government decided to quarantine the ship in hopes of limiting Japan’s exposure. Governmental investigators started to test passengers with symptoms and their close contacts. Those who tested positive were taken off the ship for isolation and care. The number of infections increased steadily, however, eventually rising to 621 today, making the outbreak on the Diamond Princess the largest outside of mainland China.

In a press conference on Monday, Japanese public health expert Shigeru Omi, head of the Japan Community Health Care Organization, defended the strategy. “Japan’s decision, at that time, to quarantine the passengers was appropriate and justified,” Omi said. He presented data suggesting most passengers were infected before the start of the quarantine, although crew members and those sharing cabins may have contracted the virus on the ship itself, said Omi, who previously headed the western Pacific regional office of the World Health Organization. But the data he presented only covered the first 168 passengers and crew who became ill or their close contacts who tested positive. (Omi was not involved in setting the quarantine policy, but is now advising the government on dealing with the broader COVID-19 challenge.)

Many others say there is no doubt that the ship has become a floating hot zone. “The quarantine process failed,” Anthony Fauci, director of the U.S. National Institute of Allergy and Infectious Diseases, bluntly said in a 17 February interview with USA Today. “There were people getting infected on that ship,” he said. “So something went awry.”

The cruise ship was completely inadequate in terms of infection control.

Kentaro Iwata, Kobe University

Concerned about the growing numbers of cases, Iwata talked his way around numerous bureaucratic roadblocks before finally joining a disaster management medical team that boarded the ship yesterday, he explains in his video. Appalled by what he found, Iwata says he started to make suggestions on how emergency team members and others coming aboard could protect themselves to minimize the chance of carrying the virus ashore. But he was ordered to leave after only 2 to 3 hours, he says. He posted his video later yesterday evening. While fighting back tears, he explained why he went public: “I can’t bear” the thought that conditions aboard the ship could lead to more infections, he said.

Scientists say Japan faced a difficult choice, however. It might have been better to house the Diamond Princess passengers and crew on land nearby during the 14-day quarantine period, Simon Clarke, a microbiologist at the University of Reading, said in a statement today. But finding accommodations for 3700 people for 2 weeks, plus medical staff to look after them, “would have presented a significant obstacle,” he said. Moreover, if the virus spread to the local population, “that would have caused serious logistical and political problems for local health authorities.”

Epidemiologists could learn a lot from what happened aboard the ship, but that information has been slow to come out. A governmental research team has collected data that are now being analyzed and will be published “soon,” Takaji Wakita, director-general of the National Institute of Infectious Diseases (NIID) said at Monday’s press briefing. But neither Wakita nor an official at Japan’s ministry of health could say who oversees this scientific effort. The delay could hamper worldwide efforts to understand the illness, says Hitoshi Oshitani, a virologist and public health specialist at Tohoku University. “I’ve been telling [health ministry officials] they need to share this data with the international community as soon as possible,” Oshitani says.

Japan lacks an agency like the U.S. Centers for Disease Control and Prevention, charged with applying research to public health, Oshitani says: “NIID is focused on basic research.”

As for the Diamond Princess, Oshitani says, quarantining a ship “is a 19th century strategy.” Those now leaving the Diamond Princess probably agree. The 300-plus Americans who left the ship Sunday night and flew to the United States in a chartered flight arranged by the U.S. government face another 2 weeks in quarantine on military bases in California or Texas. Repatriated nationals of other countries face similar quarantines. But Japan began to release the first remaining passengers today after they tested negative for the virus. They are now free to travel within Japan. Testing and releasing all remaining people on board is expected to take several days.

In his video, Iwata said he spent time in Africa to aid the fight against Ebola, was in China during the 2003 severe acute respiratory syndrome crisis, and has helped out in many countries during cholera outbreaks. “I never feared getting an infection myself,” he said, because he knows “how infection control should be done.” But aboard the Diamond Princess, “I was so scared of getting COVID-19,” he said.