A new virus gaining traction in China has begun a global spread, and the world is taking notice.

China has reported more than 500 cases of the virus since December, most of them in the city of Wuhan. At least 17 deaths are blamed on the outbreak. The virus is spreading across China, and beyond: One case has been confirmed in Japan, two in Thailand, one in South Korea and one in the U.S.

A Washington state native contracted the virus, the Centers for Disease Control and Prevention confirmed Tuesday. The man, in his 30s, had recently visited Wuhan and was in good condition at a local hospital, the CDC said.

Coronavirus death toll rises to 17: experts consider public health emergency

Many of the initial cases were linked to a seafood market in Wuhan, but Chinese health officials said this week that human-to-human transmission has been confirmed.

The Lunar New Year is Saturday, and officials are concerned that millions of holiday travelers across Asia will fuel spread of the disease.

"From a public health perspective, vigilance is necessary now," said Ogbonnaya Omenka, an assistant professor and public health specialist at Butler University's College of Pharmacy and Health Sciences. "Community-led surveillance systems can be very effective in detecting – and nipping in the bud – infectious diseases."

WHO has published a range of interim guidance for all countries on how they can prepare for the virus, including how to monitor for sick people, test samples, treat patients and communicate risks to the public.

The disease is drawing intense attention because of its similarities to severe acute respiratory syndrome, a coronavirus that killed more than 600 people across mainland China and Hong Kong along with more than 100 other people around the world in 2002-2003.

Coronavirus outbreak:First US case of coronavirus reported in Washington state

Here's what to know about coronavirus:

What is coronavirus? What are the symptoms?

Coronaviruses are a large family of viruses that cause illness ranging from the common cold to more severe diseases such as pneumonia to Middle East respiratory syndrome, known as MERS, and severe acute respiratory syndrome, or SARS. Common signs of infection include fever, cough, shortness of breath and breathing difficulties. In more severe cases, infection can cause pneumonia, severe acute respiratory syndrome, kidney failure and death.

What is the world doing about it?

The World Health Organization has established an emergency committee to advise Director-General Tedros Adhanom Ghebreyesus on whether the outbreak constitutes a public health emergency of international concern, or a PHEIC.

Declaring a PHEIC gives the WHO director-general powers to issue recommendations to other countries, such as urging them not to close borders or restrict trade with a country in the throes of an outbreak.

How is coronavirus similar to Ebola, MERS and SARS?

Coronaviruses, Ebola and SARS are zoonotic, meaning they are transmitted between animals and people. Ebola was carried by fruit bats, which spread it to other animals. SARS was transmitted from civet cats to humans and MERS from camels to humans.

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Should Americans be afraid of coronavirus?

The Washington man who contracted the virus flew indirectly from Wuhan to Seattle-Tacoma International Airport, CDC said Tuesday. He arrived in Washington on Wednesday, passing through the airport before the CDC and Customs and Border Protection began enhanced health screenings at several airports to detect travelers sickened by coronavirus coming into the United States from Wuhan.

Those screenings began Friday at airports in San Francisco, New York and Los Angeles. Screenings were also expected to begin in Chicago and Atlanta, and all flights from Wuhan were being redirected to these five airports, the CDC said Tuesday.

"With global travel, the spread of any infectious disease is literally a plane ride away," says Robert Glatter, an emergency physician at New York's Lenox Hill Hospital.

Glatter, however, said perspective is important.

"It’s more likely that you would encounter the flu compared to the coronavirus," Glatter said. "It’s the flu and measles which pose a greater threat to the global community at this time."

Is coronavirus contagious? How is transmitted?

The virus can be spread from animals to people. But it also can be spread by coughing, sneezing and through close contact with an infected person or an object carrying the virus.

Is there a coronavirus vaccine? What does treatment look like?

There is no vaccine yet. Nine studies are examining coronavirus vaccine development.

"Development of vaccine is a complex process, and it's not going to be available tomorrow," said Nancy Messonnier, director of the National Center for Immunization and Respiratory Diseases.

While there is no particular treatment for the coronavirus, recommended measures are similar to those for cold, such as rest and drinking a lot of fluid.

Contributing: Grace Hauck, USA TODAY