How to beat the next epidemic

The effort to develop an Ebola vaccine has made progress recently, but too late to save those who died during last year's epidemic. Scientists are now racing to find a vaccine against the zika virus. Andrew Ward, FT pharmaceuticals correspondent, asks Charlie Weller of the Wellcome Trust why scientists are so often behind the curve. Music by David Sappa Read more on vaccines in an FT Special Report at ft.com/vaccines