With the Zika epidemic in Brazil being declared an international health emergency just months after the recent Ebola epidemic in West Africa, Jim Al-Khalili talks to Professor Peter Piot about a lifetime spent trying to stop the spread of deadly viruses.

Peter came across a strange new virus in 1976 when he was working in a small lab in his home town, Antwerp. Weeks later he was in Zaire meeting patients and trying to understand the transmission routes of this terrifying new virus which, together with colleagues, he named Ebola. Thousands of miles from home and surrounded by people dying, he says he felt very much alive. His career path was set.

He was heavily involved in the recent Ebola epidemic but most of Peter's career has been devoted to stopping the transmission of another deadly virus, HIV. He spent most of the eighties trying to convince the world that HIV/AIDS was a heterosexual disease and much of the nineties trying to mobilise the World Health Organisation and other UN agencies to take the threat posed to the world by HIV more seriously. It wasn't easy.

Today he is Director of the London School of Hygiene and Tropical Medicine in London.

Producer: Anna Buckley.