US health officials are reporting the first case of person-to-person spread of the new coronavirus from China. The news comes as the World Health Organization on Thursday declared the virus a public health emergency.

The latest US victim is married to a Chicago woman who got sick from the virus after she returned from a trip to Wuhan, China, which is ground zero for the outbreak. This brings the number of confirmed cases in the United States to six.

That's barely a fraction of the 8,000 cases worldwide. All but 120 of those cases are in China, as have been all coronavirus-related deaths.

The fast-moving virus is prompting governments worldwide to take decisive measures out of an abundance of caution. For example, 6,000 passengers were held on a cruise ship off Italy Thursday while doctors checked two Hong Kong tourists who were running a fever.

In addition, several countries are racing to help citizens escape the contagion by flying them out of China, especially those in Wuhan, the disease epicenter.

A chartered flight with some 200 Americans touched down at a California military base on Wednesday. Patrick Stockstill and his family were among passengers in face masks and officials in hazmat suits.

"When we first stepped on board, my jaw dropped," Stockstill said. "I've never seen a plane set up like that before. Cargo plane with passenger seats. Honestly, it felt like something out of a movie."

But it's all too real. Those passengers will remain quarantined for three days, longer if they show any symptoms.

Efforts to keep the outbreak in check have grown to screening checkpoints at 20 airports across the country.

"Americans should know this is a potentially very serious public health threat, but at this point, Americans should not worry about their own safety," said Secretary of Health and Human Services Alex Azar.

Airlines around the world have announced the complete suspension of flights to China until further notice. The White House has reportedly considered banning all flights from the US to China but hasn't taken that step yet.

Watch the video below from the World Health Organization for more information on the Coronavirus: