What is the virus?
The virus itself is a new coronavirus, a family that normally affects animals.
One human variant causes the common cold, but another, SARS, killed hundreds in a major outbreak in 2003.
This new virus causes severe acute respiratory infection.
Symptoms seem to start with a fever, followed by a dry cough and then, after a week, leads to shortness of breath and some patients needing hospital treatment.
There is no specific cure or vaccine.