A Japanese doctor treating COVID-19 patients in New York — a hotspot of infections — has issued a strong warning over the virus situation in Tokyo, saying that Japan's capital now "looks like" New York two to three weeks ago.

The number of people confirmed daily as infected with the virus in Tokyo exceeded 100 for the first time on Saturday, and continues to rise. The same situation was seen about three weeks ago in New York state, on March 12.

"News from Japan show people gathering," said Yuichi Shimada, a doctor at the cardiovascular medicine department at the Columbia University Irving Medical Center, in his message Saturday.

"People in Japan do not seem serious enough about the situation," the 37-year-old doctor observed. "In New York three weeks ago, people weren't taking basic infection prevention measures, such as wearing face masks, washing hands and avoiding closed, crowded places involving close contact," he added.

The cumulative number of people found to have been infected in New York state has exceeded 113,000, with the death toll surpassing 3,500.

In New York, ambulances are seen ferrying COVID-19 patients to hospitals all the time, Shimada said. "Ambulances are mobilized with the same frequency as that in the aftermath of" the Sept. 11, 2001, terrorist attacks on the United States, he said.

The emergency departments at New York hospitals are flooded with COVID-19 patients, he noted.

The first case in the U.S. state of infection with the new coronavirus that causes COVID-19 was reported on March 1. The infected person was a woman who returned from Iran, and the infection route for the woman was identified.

For the next case, though, the source of infection was unknown.

"In Tokyo as well, infection routes have not been identified for many infected people," Shimada said, warning that the virus may already be spreading widely in the Japanese capital.

"New York is one of only few U.S. cities where people can commute by public transportation systems, and it has many restaurants and bars where people can gather," Shimada said.

"The virus can spread easily in such major cities,” he added, “and this has actually happened. The situation in Tokyo is very similar to that of New York."

"I think the virus could spread explosively (in Tokyo) if people remain optimistic about the situation," Shimada stressed, adding, "I really hope Tokyo will not make the same mistake as New York."

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