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'Sinister family tree' of an Ebola outbreak

As part of the BBC's A Richer World season, renowned Swedish statistician Hans Rosling explains how West Africa has managed to contain the Ebola virus.

Exactly one year ago, on 23 March 2014, the World Health Organisation officially declared an Ebola outbreak in West Africa. The Ebola crisis swept through the region, particularly Sierra Leone, Liberia and Guinea.

But Prof Hans Rosling, a professor of global health at the Karolinska Institutet, argues that West Africa's handling of the crisis demonstrates how far the continent has come in terms of dealing with such risks.

In this clip, from a talk given at the BBC, he shows how almost all of the new Liberian cases in 2015 came from one woman.

Click here to watch Prof Rosling's full 15-minute talk

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