Coronavirus has flu-like symptoms, which can develop into severe respiratory problems. The current outbreak is understood to be a new strain of coronavirus, not previously found in humans.
The virus can be transmitted between humans and animals, making it harder to contain. Other strains of coronavirus are not as dangerous – the common cold is one. Authorities have said that the current strain of the virus originated at a seafood market in Wuhan, in the Hubei province of China, which has seen the most severe outbreak of coronavirus.
It is thought that the market was engaged in illegal wildlife sales, and has now been shut down.