About 3,600 passengers and crewmembers are still being quarantined on the Diamond Princess. Health minister Katsunobu Kato said on Wednesday that the new cases include a teenage girl and ten Japanese nationals.
The infected health ministry official was on board from February 3rd to 4th, collecting questionnaires and taking temperatures. He developed a fever on the 9th.
The four patients in serious condition are all males in their 60s or 70s. Two are being treated at intensive care units. Three are Japanese nationals.
Conditions on the ship
Professor Mitsuo Kaku is an infectious disease expert at Tohoku Medical and Pharmaceutical University. He says a cruise ship is the perfect setting for a virus to spread, as passengers have to hold handrails to move around while at sea.
To learn more about the conditions on the ship, the Japanese Society for Infection Prevention and Control sent a team of infectious disease experts on board on Tuesday. The group includes doctors and nurses with experience handling disease control at evacuation centers in the aftermath of natural disasters. It will stay on board until Wednesday.
The group is also evaluating preventive measures taken by crewmembers. The crew is believed to be at particular risk of infection and transmission, as they share cabins and move through the ship more frequently than passengers.
The Society says it will give the ship operator and health ministry officials recommendations on preventive measures. It says there is little doubt that mass infection is currently taking place on board but that the team will do its best to prevent further transmission.
Health ministry officials have been transporting infection passengers and crewmembers to medical institutions in Tokyo and four neighboring prefectures. But as the number of cases grows, they say they are looking at more hospitals across the country.
The health ministry recently floated the possibility of testing everyone still on board. But it is unclear whether testing more than 3,000 people at once is logistically feasible. The quarantine is currently scheduled to last until the 19th, but extending the scope of the testing could see this period extended, an outcome unlikely to please anyone still on the ship.