By Kieran Guilbert

West Africa is most at risk of fatal haemorrhagic fever epidemics, including Ebola, researchers said on Wednesday, calling for greater preparedness to save lives.

A study in The Lancet medical journal assessed the likelihood of four viruses - Ebola, Lassa, Marburg and Crimean-Congo - spreading on the continent, charting progress from a first human case through to a potential pandemic.