An unknown type of pneumonia, later identified as a new type of coronavirus, originated in the Chinese city of Wuhan, and since then, it has spread to several countries, including Japan.
A second case of Wuhan coronavirus has been confirmed in Japan, the health ministry said on Thursday.
The so-called Wuhan coronavirus was first registered in Wuhan, Hubei province, in late December, and identified as a new strain of the coronavirus. Those infected with the new virus showed symptoms of pneumonia and other acute respiratory diseases.
The World Health Organisation (WHO) labelled the Wuhan virus as 2019-nCoV or Novel Coronavirus.
The Chinese authorities confirmed the virus can be transmitted from human to human through coughing and sneezing. The virus has already been detected in Hong Kong, Macau, Taiwan, Thailand, South Korea, Japan, and the United States.
At least 17 people have died, and over 600 have been infected so far, according to the Chinese health authorities.