The first U.S. case of a new coronavirus strain that has killed at least nine people in China has been reported in Washington state, the Centers for Disease Control and Prevention said Tuesday.

The deadly virus, which Chinese health officials have said can spread by human-to-human contact, has sickened hundreds of people, according to the mayor of China’s central city of Wuhan, where an outbreak is underway. Exported cases of the illness also have been confirmed in Thailand, Japan and the Republic of Korea.

China said that as of midnight on Tuesday, 440 people had been infected in the country. Officials said nine people had died, all in Hubei province where the virus was first reported.

The male U.S. patient is a resident of Snohomish County, Washington. He was hospitalized last week in Everett with pneumonia after returning from a trip to Wuhan, health officials said at a news conference.

Darley Shen / Reuters Medical staff carry a box as they walk at China's Jinyintan hospital, where patients with pneumonia caused by the new strain of coronavirus are being treated, in Wuhan, Hubei province.

“We believe the risk to the public is low,” Washington state Secretary of Health John Wiesman said. Wiesman credited the patient’s decision to seek immediate medical help for helping prevent the virus from spreading.

The patient was described as being in good condition on Tuesday. He remained hospitalized for short-term monitoring out of an abundance of caution, said Chris Spitters, health officer for the Snohomish Health District.

The CDC on Monday said it has been actively screening incoming travelers from Wuhan City in Hubei Province.

Darley Shen / Reuters Medical staff transfer a patient at the Jinyintan hospital, where the patients with pneumonia caused by the new strain of coronavirus are being treated, in Wuhan, Hubei province, China.

The World Health Organization has said it will convene on Wednesday to determine whether the virus outbreak warrants being declared a global health crisis.

The patient in Washington returned to the U.S. on Jan. 15. This was before he began experiencing symptoms and before health screenings for incoming travelers at airports were put in place on Jan. 17.

Because the man had been following the news about the virus in China, he thought to contact health officials when he became ill, health officials said.

The man said he didn’t know of anyone in Wuhan who was ill with the virus while he was overseas, and didn’t go to a seafood and poultry market in Wuhan that has been implicated in the outbreak.