Wuhan, a Chinese city of nearly nine million people, is to temporarily shut public transport as it tries to halt the outbreak of a new strain of the virus.
Those living in the city have been advised not to leave, in a week when millions of Chinese are travelling for the upcoming Lunar New Year holiday.
The respiratory illness has spread to other parts of China, with some cases in other countries including the United States.
There are more than 500 confirmed cases and 17 people have died.
Known for now as 2019-nCoV, the virus is understood to be a new strain of coronavirus not previously identified in humans.
The Sars (severe acute respiratory syndrome) virus that killed nearly 800 people globally in the early 2000s was also a coronavirus, as is the common cold.
Meanwhile, after a day of discussions in Geneva, Switzerland, the World Health Organization’s (WHO) emergency committee has announced it would not yet declare a “global emergency” over the new virus.
The Director-General of WHO, Dr. Tedros Ghebreyesus, said more information was needed about the spread of the infection.
The committee of health experts will meet again on Thursday.
A global emergency is the highest level of alarm the WHO can sound and has previously been used in response to swine flu, Zika virus, and Ebola. (BBC)