Guinea worm is an ancient affliction. An Egyptian medical text from the 15th century B.C. mentions it, and scientists found a calcified worm in the mummy of a thirteen-year-old girl who lived in Egypt around 1000 B.C. A Sanskrit poem from the 14th century B.C. includes the plea, "Let not the sinuous worm strike me nor wound my foot."

The disease was once present in many parts of the world, including the Americas. But it slowly disappeared as drinking water supplies were improved, showing that Guinea worm is one of the most easily preventable of all parasitic diseases. By 2001, it had become a disease of the world's forgotten people, the poorest of the poor, in thirteen African countries.

The economic impact of Guinea worm is huge. The disease coincides with harvest and planting seasons, when the demand for labor is highest and workers need to consume large amounts of water, leading to re-infection. One study in southeastern Nigeria showed that rice farmers lost the equivalent of $20 million per year because they couldn't work. The same study put the school absenteeism rate over 60 percent, either because the children suffered from Guinea worm or had to labor for family members who did.

Learn about the symptoms of Guinea worm disease >>