The U.S. State Department warned Americans in China about an outbreak of pneumonia in the central city of Wuhan believed to be caused by a new strain of coronavirus, and which has killed one person.
Wednesday's notice referred to an alert by the U.S. Centers for Disease Control and Prevention urging citizens in China traveling to Wuhan to avoid contact with animals, animal markets or animal products, among other precautions.
It also asked citizens those who had visited Wuhan and feel sick to seek medical care.
Chinese health authorities have reported 41 cases caused by the new virus strain.
On Tuesday, the World Health Organization warned a wider outbreak was possible, though China has not reported any new cases since.