The 2019 novel coronavirus has landed in the state of Washington, but experts say it may pose a less significant health threat than the flu for people in the United States.

One person in Western Washington is confirmed to have the viral infection, another eight people are being tested, the Washington state Department of Health reported Monday evening.

Another 63 people are considered “close contacts” because they were potentially exposed to the virus by being within 6 feet of an infected person.

A challenge of the novel coronavirus is that, because it’s new, experts are still uncertain how contagious the disease is and what the mortality rate is for those infected, said Guy Palmer, regents professor of pathology and infectious diseases and senior director of Global Health for Washington State University.

Early data suggests the percentage of novel coronavirus infections that result in death is around 3% and that the virus does not pose a significant danger to the general public in the United States, he said.

“Early on in cases like this, the case fatality rates are really high because we first detect these in hospitals, so we detect it in people who are sick,” Palmer said. “You’re not picking up those people who, yes, they have a cough, they stay home, and four or five days later they feel better.”

Some people with already-compromised immune systems may also be at greater risk, but the chances of being infected in the first place are fairly low. The median age for infected patients outside of China is 45 years old, according to the World Health Organization.

The disease is thought to have originated in a fish market in Wuhan, China. So far the outbreak has reached 16 countries outside China, with about 3,000 confirmed cases worldwide, according to the Wednesday update by the World Health Organization. Most of those cases are in the Chinese province in which the disease originated. The death toll is more than 80. The virus is from the same family of respiratory viruses as SARS, which killed 774 people in 2002-03, according to the CDC.

The new virus is believed to spread between people through droplets in the air and close personal contact, so standard precautions to avoid illness, such as frequent hand washing, disinfecting and covering coughs and sneezes, are advised.

A Snohomish County resident in his 30s developed symptoms on Jan. 16 and was diagnosed with the virus, but the risk of infection is low even for those who traveled through the Sea-Tac Airport at the same time as the patient, who arrived on a Jan. 15 flight, according to Public Health Seattle and King County.

The patient remains in satisfactory condition at Providence Regional Medical Center in Everett.

“If you look at something like our seasonal flu, it’s actually on a population basis much more impactful,” Palmer said.

The Centers for Disease Control and Prevention estimates that this season alone there have been approximately 140,000 hospitalizations and 8,200 deaths from flu. So far in the U.S., there are five confirmed cases of coronavirus.

The only uncertainty, Palmer said, is that while many people have been vaccinated or already contracted the flu before, the population at large does not have immunity against novel coronavirus.

“If you think of seasonal flu,” Palmer said, “there’s actually a kind of mosaic of immunity that’s in the population that changes that spreading dynamic. Whereas with a new virus, with this novel coronavirus, there’s really no immunity in the population.”

According to a statement by Public Health Seattle and King County, two University of Washington students who returned from Wuhan in December are being tested for the virus as a precautionary measure. A third student tested negative.

“None of the students were hospitalized and all are doing very well,” according to the statement. “Testing criteria developed by the Centers for Disease Control and Prevention (CDC) are designed to cast a wide net, and most people who have symptoms listed in the criteria will not have the disease.”

A University of Washington medical laboratory is working on a diagnostic test based on the latest genomic information, according to a news release by UW Medicine.

As of Monday, the CDC upped its travel warning for China to level 3, recommending people avoid all nonessential travel to the country.

People who get a fever, develop a cough or have difficulty breathing within 14 days of visiting China are advised to avoid contact with others and contact a doctor or other medical provider.