The first U.S. case of a deadly new strain of virus that has killed six people in China was confirmed in Snohomish County on Tuesday. Gov. Jay Inslee along with federal, state and local health officials stressed that there is a low risk to the public from the bug, which is known as the “2019 novel coronavirus.”

A Snohomish County resident in his 30s who had recently traveled through Wuhan, China, the region identified as the epicenter for the new virus, began presenting symptoms Thursday, Jan. 16, one day after he got back from a trip to visit family.

He immediately called his health care provider and went to a clinic on Jan. 19. After samples were taken, the CDC confirmed on Monday that he had the new virus, and he was hospitalized. The man is in good condition and is in an isolation unit as a matter of precaution at the Providence Regional Medical Center in Everett. He will be there for at least two more days, hospital officials said.

The novel coronavirus outbreak was initially linked to seafood and animal markets in Wuhan in December. The U.S. is the fifth country to report seeing the illness, following China, Thailand, Japan and South Korea. So far, 300 cases of the new virus have been identified, the majority of which are in Wuhan.

In China, there are 51 severe cases and 12 cases of critically ill patients, according to the World Health Organization. Six people have died from the virus, although others have been discharged with milder symptoms.

State and county health officials are working to identify who could have come into contact with the Snohomish County man and to ask those individuals to monitor themselves for at least two weeks. The CDC has a three-person team working with health officials in Washington state.

The novel coronavirus has respiratory symptoms similar to the common cold and the flu, including fever, cough and trouble breathing. Not all cases are severe, and many patients in China have had only mild illness and been discharged.

The man, who is helping health investigators identify all possible contacts he had since he has returned, is not considered a threat to medical staff or the public, although he is still hospitalized “out of an abundance of caution,” county health officials said.

“At this point, the individual has reported that he didn’t visit any of those implicated markets or know anyone who was ill. He was just traveling in that area,” said Dr. Chris Spitters, health officer in Snohomish County Health District.

Officials said the patient had no symptoms when he arrived at the Seattle-Tacoma airport on Jan. 15. Health officials had not confirmed his flight plans to trace his travel back to the U.S., as of Tuesday. Spitters said health and hospital officials are using very strict isolation protocols since this is the first identified case in the U.S., and health care workers who potentially worked with the patient have been identified and will be monitored.

“We’re very comfortable that this patient is isolated and poses very little risk to the staff and the general public,” Spitters said.

Local and federal health officials began the contact investigation Tuesday to see exactly who could have been affected or exposed to the virus by the Snohomish County man.

“That’s our priority: to determine who is at risk and what it means to be at risk,” Scott Lindquist, Washington state epidemiologist, said.

Part of the challenge for health officials is that little is known about the new virus, including how long a person is contagious or when they actually become contagious.

This new coronavirus has been commonly circulated by animals and passed on to humans, but some cases, including a case confirmed by China’s health ministry on Monday, can be transmitted person-to-person as well.

“There does need to be some limited human-to-human transmission based on the data we have today,” Dr. Satish Pillai of the CDC said at a news conference in Shoreline on Tuesday.

Those experiencing symptoms who have traveled to or been in the Wuhan area should contact their health care providers, health officials said, but stressed that just experiencing cold or flu-like symptoms without having traveled at this point is not a good indication of the virus.

Federal agencies and health officials are rerouting travelers with flights that originated in Wuhan to five U.S. airports, CDC officials said Tuesday, in New York City, San Francisco, Los Angeles, Chicago and Atlanta. These airports will be actively screening passengers for the virus.

The CDC is testing samples for the virus in Atlanta currently, but in the coming weeks, testing will be shared nationally with state health departments. The Washington State Department of Health expects to have updated information on Wednesday about the virus.