Nigeria's health minister says the country's first coronavirus case was not detected when the infected passenger arrived at the airport.

Osagie Ehanire said the Italian man travelled through the commercial capital, Lagos, before he became ill.

Officials say he is stable, with no serious symptoms.

He arrived in the country on Monday.

Mr Ehanire said all people on the flight would be contacted and observed.

He said efforts were underway to beef up preparedness, with the main focus on Nigeria's international airports.

He said there are four laboratories in the country that can perform tests for the virus.

This is the first confirmed coronavirus case in sub-Saharan Afric