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A bus carries U.S. citizens who had been aboard the Diamond Princess cruise ship to a Tokyo airport on 17 February.

Kyodo via AP Images

First deaths of cruise ship passengers fuel debate over Japan’s handling of quarantine

­­Two Japanese passengers on the cruise ship Diamond Princess have died from their COVID-19 infections, officials reported today, as the debate continued over a video alleging “chaotic conditions” on the ship. The infectious disease expert who posted the video, Kentaro Iwata of Kobe University, took it down early Thursday morning Japan time, saying it had served its purpose, including the release of additional epidemiological data about the ship.

Iwata had posted his alarming video on Tuesday night after spending a few hours on the cruise liner, which is docked in the port in Yokohama, Japan. He alleged there was “no professional infection control person” aboard the ship and said, “Bureaucrats were in charge of everything.”

During a press conference this morning from the Yokohama hotel room where he has quarantined himself, Iwata said he stands by his observations. But, he said, a trusted source told him significant improvements have been made to the separation of infection-free and potentially contaminated zones aboard the ship. In addition, Japan’s National Institute of Infectious Diseases (NIID) has posted epidemiological details on 531 passengers and crew confirmed positive for the COVID-19 virus, which Iwata thinks happened in response to the video. (Although he did not mention the lack of data in his video, Iwata said he urged the health ministry to release data 1 week ago.) “I thought the role of the YouTube post was over,” Iwata said. An NIID spokesperson directed questions about the data to Japan’s health ministry, where an official did not immediately respond to a request for comment.

At the start of the press conference, Iwata emphasized that he was presenting his personal views and did not represent Kobe University—something he did not do in the YouTube video. He insisted he had not been pressured to remove the video, but had been “asked” to do so by Yoshihiro Takayama, a member of the disaster medical assistance team he had met on the ship. Iwata said he had exchanged phone calls and text messages with Takayama, mostly on technical issues, after the video appeared. “But I never felt any pressure from him,” Iwata said.

Even before the video was taken down, Takayama posted his own point-by-point response in Japanese on Facebook. Takayama, who, according to his Facebook profile, works at Okinawa Chubu Hospital, confirmed some details of Iwata’s video but sharply disagreed with several of his conclusions. Iwata was wrong to say there were no infection control professionals on the ship, Takayama writes. “Every day, doctors who specialize in infectious diseases and public health are on board and giving guidance.” Takayama also defended the zoning efforts as being “well done, though not perfect.” 

 Iwata has been both supported and attacked on social media and even in Japan’s legislature. Iwata had warned that lax infection control on the ship would lead to more infections during the quarantine. His critics seized on the newly released NIID data, which suggest the quarantine did reduce transmission among passengers. But Iwata’s fears appeared to be confirmed by press reports that at least two government officials who visited the ship during the quarantine have become infected.

The patients who died tested positive for the virus and were taken to a hospital on 11 and 12 February, respectively. Both were in their 80s and had underlying health conditions, NHK, the national broadcaster, reported.