Medical workers with a patient in Wuhan, China, on  January 26, 2020 (Photo: Associated Press)

Hubei provincial governor Wang Xiaodong said conditions in Huanggang, which had reported 573 infections and 12 deaths, are particularly severe. He urged every effort to keep the city from becoming a second Wuhan.

The German government has sent a military plane to the Chinese city of Wuhan to evacuate over 100 of its citizens from the virus-hit region. The outbound flight also delivered 10,000 protective suits to China.

The World Health Organization (WHO) said on Friday that borders should be kept open and people and trade flowing in the face of the coronavirus outbreak, although countries have a sovereign right to take measures to try to protect their citizens.

The WHO, which declared the accelerating outbreak a global emergency on Thursday, voiced fresh concern that the virus could spread undetected in a country with a weak health system.