During the twentieth century, the world lived through a golden era in public health: vaccines were discovered, diseases were cured, and the average life expectancy rose by many years. In recent decades, however, this stunning progress has declined dramatically. Although life expectancy remains high in developed nations, in many countries of the developing world it has actually fallen.

We take medicines and basic hygiene for granted, but only in the past two centuries have we had vaccines and even something as basic as clean drinking water. That, coupled to effective sewerage, has been a major factor in improved public health, life expectancy and the growth in the world’s population.

Narrated by film star Brad Pitt, who with his partner Angelina Jolie has funded many public health projects, this new six-part series traces pioneering moments in the history of health.