A preschooler in Saitama and two brothers in Hokkaido have been confirmed infected with the new coronavirus, prefectural officials announced Friday.

The preschooler was confirmed to have the virus Friday by the Saitama Prefectural Government. The boy returned with his father from Wuhan, China, on a Japan-chartered flight on Jan. 30. His infection is said to be light and not life-threatening. His dad tested positive on Feb. 10.

The two in Hokkaido are students at an elementary school in the town of Nakafurano, according to prefectural officials. One is under 10 years old.

It is the first time someone under 10 has caught COVID-19 in Japan.

The younger Hokkaido boy visited a medical institution after developing a fever Saturday. He was hospitalized on Wednesday and is now recovering. His brother developed a fever on Tuesday. He was admitted to a hospital on Wednesday and is also recovering.

The brothers have no history of travel abroad and the prefectural government is investigating how they became infected.

Prefectural officials also said a female quarantine officer in her 40s who lives in Chitose has been infected.

The cases came as the health ministry said Friday that it will encourage more companies to promote telecommuting and staggered working hours as part of efforts to prevent the virus from spreading further.

The ministry will make the request through Keidanren (the Japan Business Federation) and other lobbies. It will also ask firms to let employees with fevers or other symptoms of illness to take time off at ease.

“We need the understanding of companies to keep the virus from spreading,” Health, Labor and Welfare Minister Katsunobu Kato said at a news conference.

Confirmed infections in Japan had exceeded 730 as of Friday. The outbreak, which began in China, has infected more than 76,000 people globally.

Also on Friday, the third and final group of around 450 passengers form the Diamond Princess who tested negative for the virus finally disembarked. The ship was quarantined for two weeks at Yokohama port.

About 720 passengers have left the ship over the past two days. The quarantine ended on Wednesday.

The ship arrived with some 3,700 passengers and crew. Two Japanese who were subsequently taken to medical facilities died after being infected with the virus.

The ministry said over 100 passengers who had close contact with those infected by sharing rooms will also disembark and move to a government-provided facility, scrapping the original plan to make them stay another 14 days.

The government will keep foreign passengers awaiting charter flights to their home countries on board.

Foreign Minister Toshimitsu Motegi said at a news conference that 759 people have been evacuated by the U.S., South Korea, Australia, Hong Kong, Israel and Canada.

Britain, Italy and Taiwan had plans to send planes for their citizens as early as Friday night, Motegi said, adding, “We will do everything we can to support foreign nationals.” Indonesia and the Philippines also plan to send planes, he said.

The departures have come amid mounting criticism of the government’s handling of the outbreak. The virus, which originated in China’s Hubei Province, appeared to spread on the ship during its two-week quarantine.

The quarantine, intended to prevent the virus from spreading in Japan, has been criticized for potentially worsening the outbreak on the ship.

RELATED PHOTOS Hokkaido Gov. Naomichi Suzuki speaks about new COVID-19 cases in his prefecture at a news conference Friday. | KYODO