The U.S. State Department issued a new travel advisory Thursday telling its citizens not to travel to China due to the novel coronavirus.

Level 4 – Do Not Travel is the most severe travel advisory, which came after the World Health Organization declared the deadly outbreak an emergency of international concern.

“Travelers should be prepared for travel restrictions to be put into effect with little or no advance notice,” the department said in a release. “Commercial carriers have reduced or suspended routes to and from China.”

The statement asked U.S. citizens in China to consider leaving the country using

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