Japan’s Hokkaido May Have 940 Infected, Researcher Says

(Bloomberg) -- The number of people infected with coronavirus in Japan’s northern island of Hokkaido may have reached 940 last month, more than 10 times the official figure, according to one scientist.

The estimate for infections as of Feb. 25 was compiled by Hiroshi Nishiura, a professor who specializes in statistical modeling of infectious diseases at Hokkaido University’s medical school. It was based on the number of foreign and domestic travelers who had been infected on the island, as well as passenger volume.

“The difference from the reported cases is about 10-fold, so it’s likely there are people who only have minor symptoms or have not developed any,” Nishiura told reporters on Monday. “My guess is that many of them are younger people.”

Hokkaido, a popular tourist spot that draws millions of visitors from around the world every year, has been a hotbed of infections in Japan. With about 77 confirmed cases, the island accounts for more than a quarter of the total in the country, excluding those related to the Diamond Princess cruise ship. Hokkaido declared a state of emergency last week, set to be in place until March 19.

Japan’s efforts to contain the spread of the coronavirus have come under increased scrutiny, as people questioned the scale of the testing and the handling of the cruise ship’s quarantine. The country also has more at stake as it’s preparing to host the Summer Olympics. Prime Minister Shinzo Abe has since attempted to tackle the problem by asking all schools to close for a month and promising to expand testing.

Japan’s health minister Katsunobu Kato acknowledged last week that Japan was conducting only a fraction of the number of tests as its peers, meaning the cases confirmed so far may only be the tip of the iceberg. Kato said Tuesday he is aware of Nishiura’s projected figures in Hokkaido and would tackle the situation accordingly.

Clusters have emerged across Hokkaido, home to more than 5 million people. Tracking the path of some cases hasn’t been possible because some of those infected haven’t shown the typical symptoms, governor Naomichi Suzuki has said.

The Health Ministry has sent personnel to the northern island to help tackle the cluster of infections.

--With assistance from Isabel Reynolds.

To contact the reporter on this story: Lisa Du in Tokyo at ldu31@bloomberg.net

To contact the editors responsible for this story: Rachel Chang at wchang98@bloomberg.net, Kana Nishizawa, Kazunori Takada

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