Compared to smallpox or typhoid, malaria is proving one of the most challenging human diseases to eradicate – and so remains a real and constant danger to nearly half the world’s population. Twenty years ago, two million people died each year on average from malaria, according to the World Health Organization (WHO). Despite numerous advances in treatment, 212 million cases were reported in 2015 alone and an estimated 429,000 people died from the disease.