Director, London School of Hygiene and Tropical Medicine - Professor Peter Piot

The warnings about Ebola have been apocalyptic - Liberia's defence minister says it threatens his country's existence, while the US president says it threatens 'global security'. Three thousand people have already died from the disease and the World Health Organisation warns the number of cases is likely to exceed 20,000 within weeks - and it is spreading. America has diagnosed the first case outside Africa. Hardtalk speaks to professor Peter Piot, the man who first identified the disease back in the 70s. Forty years on we still do not have a cure. So, what should be done to stop it?