Feb. 10 (UPI) -- More passengers aboard the quarantined Diamond Princess cruise ship in Yokohama, Japan, have tested positive for the deadly coronavirus since last week, raising questions about whether Japanese authorities are doing enough for the people on board.
Infections may be spreading quickly among elderly passengers; nearly 80 percent of coronavirus patients aboard the ship are in their 60s or older, Japanese television network NHK reported.
Japan ordered the quarantine last week, after a guest from Hong Kong tested positive for coronavirus on Feb. 1. A few days later, 10 passengers on the Diamond Princess were diagnosed with 2019-nCoV. As of Tuesday, 135 people have tested positive, according to reports.
Japan's health authorities have responded in part by evacuating 91 patients from the ship on Tuesday, after initially enforcing a two-week isolation period, effective until Feb. 19, to contain the virus on a ship that includes more than 3,600 passengers and crew.
Health authorities in Japan have been slow to respond to the needs of the passengers stranded on the ship. In the past week, only 439 out of the more than 3,600 people on board have received 2019-nCoV tests, South Korean network JTBC's Tokyo correspondent reported Tuesday.
The government's decision to run tests exclusively at state-run public health labs is creating bottlenecks at a time of a global health crisis, according to the report. Japan is currently reporting the highest number of infections after China, the origin of the outbreak.
On Monday, as Japan's health ministry confirmed another 65 coronavirus patients, frustration is growing among local experts.
Masahiro Kami, head of the Medical Governance Research Institute, a Japanese nonprofit, said the quarantine may be posing grave problems for uninfected passengers on the ship.
"Since the infections began in an enclosed space, if this continues, [the number of patients] will steadily increase," Kami said. "One minor error and I think a person [on board] can become infected."
A total of 25 Americans on the ship are confirmed for the virus, according to Japan's health ministry.
Kyodo News reported Tuesday elderly passengers on the ship suffer from chronic health problems.
A passenger who spoke to the Japanese news agency said full medical care is not reaching the ship though there are "many people whose health is deteriorating."