From Scientific American:
In the north of Burkina Faso, not far to the east of one of the best-known backpacker destinations in West Africa, the Bandiagara Escarpment in Mali, lies the town of Koumbri. It was one of the places where the Burkina Ministry of Health began a mass campaign five years ago to treat parasitic worms. One of the beneficiaries, Aboubacar, then an eight-year-old boy, told health workers he felt perpetually tired and ill and had noticed blood in his urine. After taking a few pills, he felt better, started to play soccer again, and began focusing on his schoolwork and doing better academically. The Burkina Faso program, which treated more than two million children, was both a success story and an emblem of the tragedy of disease in the developing world. For want of very simple treatments, a billion people in the world wake up every day of their lives feeling sick. As a result they cannot learn in school or work effectively.
Most people in richer countries equate tropical disease with the big three—HIV/AIDS, tuberculosis and malaria—and funding agencies allocate aid accordingly. Yet a group of conditions known collectively as neglected tropical diseases (NTDs) has an even more widespread impact. They may not often kill, but they debilitate by causing severe anemia, malnutrition, delays in intellectual and cognitive development, and blindness. They can lead to horrific limb and genital disfigurement and skin deformities and increase the risk of acquiring HIV/AIDS and suffering complications during pregnancy. They not only result from poverty but also help to perpetuate it. Children cannot develop to their full potential, and adult workers are not as productive as they could be.