Updated at 5:45 p.m.

The new coronavirus that has infected about 300 people in China and killed at least six has reached the United States with a man in Snohomish County, Washington, identified Tuesday as the first confirmed case here.

The man, in his 30s, began experiencing symptoms after returning from a recent trip to China and was described as “quite ill,” state and federal officials said. As of Tuesday morning, he was at a hospital in Everett, Washington.

The U.S. Centers for Disease Control and Prevention said in a statement that it “is working closely with the state of Washington and local partners. A CDC team has been deployed to support the ongoing investigation in the state of Washington, including potentially tracing close contacts to determine if anyone else has become ill.”

The Oregon Health Authority is paying close attention to the outbreak, though the current level of concern is “moderate,” said public health physician Paul Cieslak.

“It’s really hard to know right now" how bad it will get in Oregon, Cieslak said.

But the state has asked hospitals to take several steps in case an infected person does make it to Oregon. The health authority requested that all health care providers get detailed travel history from any patients that come in with a fever and acute respiratory illness. If the patients say they’ve been to Wuhan in the prior two weeks or have had close contact with someone being investigated in the outbreak, doctors should report the case to health authorities.

The agency hasn’t asked doctors to ask patients if they’ve been to Snohomish County, Cieslak said. The victim there was sequestered quickly, he said, so he expects the likelihood of any secondary infections spreading to Oregon from that person to be low.

The U.S. Centers for Disease Control and Prevention says that people can reduce the risk of an infection by washing their hands often with soap and water for at least 20 seconds, avoiding touching their eyes, nose and mouth with unwashed hands and avoiding contact with sick people. To protect others, the CDC says sick people should stay home, avoid close contact with others, cover their mouth with a tissue when sneezing or coughing – then dispose of that tissue and wash their hands – and disinfect the things and surfaces they touch.

Symptoms of this coronavirus include fever, cough and trouble breathing. While some patients have had severe symptoms and some have died, others had a mild illness, the CDC said.

Overall, it appears it’s not time to panic.

The risk “to the American public at large remains low at this time,” the federal agency said.

The international outbreak, believed to have started last month at a poultry-and-seafood market in the Chinese city of Wuhan, has already prompted federal officials to begin taking steps to protect the U.S. public. Three major airports – in New York, San Francisco and Los Angeles – have begun screening passengers traveling from or connecting through Wuhan. Screenings also are being added at airports in Atlanta and Chicago.

There are now seven know coronaviruses that can infect people, four of them causing mild symptoms like a common cold. In addition to the type currently infecting people in China, two others – SARS and MERS – have killed people.

In the early 2000s, SARS, or severe acute respiratory syndrome, infected about 8,100 people and killed about 800 worldwide, according to the CDC. Medical experts have likened the current coronavirus to SARS, which also started in China.

The CDC has a website with the latest information about the outbreak.

Fedor Zarkhin contributed to this report.

-- Douglas Perry

@douglasmperry

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