Many of these diseases cause tremendous suffering and death -- yet there's still a lack of effective tools to diagnose, treat, and prevent them.
Among the health conditions that might have faced a setback is leishmaniasis, a parasitic disease associated with poverty. It can cause devastating lifestyle changes, disability, and even death.
There's a big market for new treatments for TB, malaria and other ailments. But most of these diseases afflict low-income people unable to pay for medicine.
Each year 50 000 people from 89 countries, in every continent except Antarctica, die from leishmaniasis, an ancient neglected disease.
A team of medievalists and scientists look back to history – including a 1,000-year-old eyesalve recipe – for clues to new antibiotics.
Emerging diseases on which the experts are keeping a close eye.