HOUSTON — Three more cases of the Wuhan coronavirus have been confirmed in the United States, bringing the total number of cases to 11.

Major travel restrictions are also in place at airports across the country.

Any U.S. citizen who has been to China over the past two weeks is being diverted to one of 11 airports to be checked and possibly quarantined for 14 days.

The Centers for Disease Control and Prevention is calling the spread of the virus “explosive,” with more than 17,000 cases reported globally.

Health officials said researchers around the world are trying to figure out exactly how the new virus is spreading and how to treat it.

Here’s what they know so far about the novel coronavirus.

The CDC said patients with the virus show signs of fever, cough and shortness of breath.

Cases have ranged from mild to severe. Some patients have needed oxygen.

The serious cases have been elderly patients or people with underlying health conditions.

So far, coronavirus has not been fatal in the United States.

At least 360 people have died in China.

There’s been one death reported in the Philippines.

That puts the death rate for the virus at about 2%.

Health officials hope that number will go down as more people with mild symptoms get tested.

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