Before the Wuhan virus reached the US, it had already started to spread across Asia.
South Korea, Japan, and Taiwan each have one confirmed case, and two cases have been recorded in Thailand.
On Tuesday, the Centers for Disease Control (CDC) announced that a man in his 30s who lives in Snohomish County, north of Seattle, Washington, had contracted the virus. The man had recently returned from a trip to China and is now in good health.
"I think it's laudable that the Chinese authorities have identified this quickly," Hyzler said. "There seems to be a good sharing of information."
Passengers traveling to the US from Wuhan will be rerouted to one of five airports.
The CDC announced Tuesday that five US airports — New York's John F. Kennedy International Airport, San Francisco International Airport, Los Angeles International Airport, Hartsfield-Jackson Atlanta International Airport, and Chicago O'Hare International Airport — will begin screening passengers for the virus.
Airports in Hong Kong, Singapore, Thailand, and South Korea are also screening passengers for fever.
"Screening is a very imperfect tool, but it's the only tool we have to try and prevent the importation of a disease," Eric Toner, a senior scientist at Johns Hopkins University, told Business Insider.
Travelers should avoid close contact with people who are sick — particularly those with cold symptoms.
Some people who contracted the Wuhan virus reported symptoms including a fever, chills, headaches, and a sore throat. A few said they had difficulty breathing.
Travelers should try to avoid contact with people that display symptoms similar to those of pneumonia or the common cold, such as coughing or runny noses.
"What we don't know is to what extent this disease can be transmitted by people who are only mildly ill," Toner said. "That's one of the things that we're trying to figure out right now."
Wearing a mask isn't particularly helpful, Toner said.
Many people in China have lined up to purchase face masks, which have reportedly started to sell out at some stores. But Toner doesn't think a mask will do much to protect anyone's health.
"There's little harm in it," he said. "But wearing masks, except in the situation of a healthcare provider, has never been shown to be a very effective way to protect yourself from infectious diseases."
The CDC warns travelers not to touching their eyes, nose, or mouth with unwashed hands.
Travelers should wash their hands frequently with soap and water, making sure to scrub for at least 20 seconds, the CDC says. There are no vaccines to protect humans from contracting a coronavirus.
"There is no cure for this virus," Hyzler said. "If there is a vaccine, it'll take years."
If you're traveling to China, steer clear of live animals.
Although scientists have traced the Wuhan virus to a local seafood market with live animals, they're not yet sure which animal spread the virus to people.
Recent research suggests the SARS virus in China may have spread to humans from horseshoe bats.
"Ever since SARS, there have been calls for improving or closing down the live animal markets in China," Toner said. "There's an awful lot we don't yet know, but it is fair to say that live animal markets are a threat not just to the people who work in them, but to public health more generally."
If you do become ill after traveling to China, report your symptoms to a health authority right away.
Toner said people who are ill and have visited China recently should tell a doctor about their travel history.
But restricting travel in areas that already have cases of the virus isn't likely to be effective, he added.
"I think they're doing the right things," he said of the Chinese government's response. "They are screening for patients or passengers that are coming in. They are trying to educate them to make sure they get care. They're trying to isolate them as soon as they start getting sick. These are the things that prevent a transmission."
- Read more about the Wuhan virus:
- What you need to know about China's Wuhan coronavirus and how it could affect you
- Everything we know about the mysterious, deadly Wuhan virus sweeping across China
- A mysterious virus in China is a reminder that the world isn't ready for a pandemic. Bill Gates says we should prepare for a deadly outbreak as we do for war.
- The spread of China's mysterious fatal Wuhan virus is poised to get infinitely worse as the Chinese New Year travel rush begins
- A video of medics in hazmat suits scanning plane passengers for China's mysterious Wuhan virus is stoking fears of a global epidemic
