Unknowns of the new virus make global quarantines a struggle

Health authorities are scrambling to halt the spread of a new virus that has killed hundreds in China. But with important details about the illness and how it spreads still unknown, officials and medical personnel are struggling.

Governments have rushed to get their citizens out of China while also restricting visitors from the country, which is orchestrating history's largest anti-viral campaign by blocking 50 million people from leaving Wuhan, the center of the outbreak, and nearby areas.

A growing number of Chinese cities are discouraging people from even leaving their apartments. Villages have blocked entry points with piles of dirt and rubble, while businesses and offices remain closed indefinitely.

As Beijing's authoritarian leadership faces questions over having kept its citizens in the dark for weeks before infections started to explode, other countries are trying to set up effective quarantines to stop a possible pandemic.

Those efforts have not always been smooth, with violent protests near quarantine centers, banishment to remote islands, the confinement of thousands on a cruise ship, and some citizens allowed to leave quarantine early.

A look at the world's sometimes-wobbly efforts to stop the crisis: ___