Since last Wednesday, all passengers arriving from China are being screened at Addis Ababa's Bole International Airport to check for infections.

At a press conference in Addis Ababa, Health Minister Dr Lia Tadesse and other officials said all four of the suspected cases were Ethiopian nationals.

Three of them were students who had travelled back from various universities near Wuhan city, the epicentre of the outbreak.

Health officials say blood samples are to being sent to South Africa for further investigation.

To date Ethiopian Airlines has screened more than 22,000 passengers for symptoms of the deadly virus.

More than 100 people have now died in China, with confirmed infections surging to more than 4,500.

The virus causes severe acute respiratory infection and symptoms seem to start with a fever, followed by a dry cough. After a week, some people can experience shortness of breath and need hospital treatment.

The virus itself is a new, or "novel" coronavirus - a family that normally affects animals.

Dr Lia Tadesse (right) at the press conference