A top U.S. health official said Sunday that more than 40 Americans aboard a quarantined cruise ship in Japan have tested positive for the coronavirus.
 
"Forty of them have gotten infected," Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases at the National Institutes of Health, said on "Face the Nation," referring to passengers aboard the Diamond Princess cruise ship. "They are not going to go anywhere. They're going to be in hospitals in Japan."
 
The Diamond Princess has been in the port city of Yokohama for more than a week with passengers aboard the ship under mandatory quarantine. The quarantine is scheduled to end February 19, but the U.S. will begin evacuating some Americans earlier.

Fauci said that American passengers will undergo a health screening before boarding a plane to return to the U.S. Those who exhibit symptoms will not be permitted to return and instead will stay at hospitals in Japan. Others "are going to be evacuated starting imminently" to Air Force bases in the U.S.

If passengers on the plane develop symptoms, they will be segregated. Once the Americans from the Diamond Princess arrive back in the U.S., they will be subject to another 14-day quarantine.

"The reason for that is the degree of transmissibility on that cruise ship is essentially akin to being in a hot spot," he said. "A lot of transmissibility on that cruise ship."

There have been more than 350 confirmed cases of the coronavirus on board the cruise ship, which makes it the site of the largest outbreak outside of mainland China. 

Tens of thousands of people worldwide have been infected by the coronavirus, with the majority of cases in mainland China. More than 1,600 people have died from the virus, which has spread to more than 24 countries.

Some of the confirmed cases are on their second or third transmission, Fauci said, adding that while the coronavirus isn't technically a global pandemic, it is trending that way.

"The [World Health Organization] wouldn't be calling this a global pandemic," he said. "But it certainly is on the verge of that happening reasonably soon unless containment is more successful than it is right now."

In the U.S., there are 15 confirmed cases, but none of the patients are said to be suffering serious symptoms.

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