More food and money, less disease: Senegal's surprising eco-experiment

In the dry, dusty Sahel region of Senegal, just south of the Sahara Desert, a team of researchers is trying to solve three big problems at once with one simple solution: fish. They are adding hundreds of fish—African bony tongue fish and tilapia—into rice paddies. The goal is to simultaneously fight a debilitating parasitic disease, boost rice production, and reduce poverty among farmers. NPR Global Health Reporter Jonathan Lambert traveled to Senegal to witness the early stages of this ambitious experiment, which is now scaling up across 60 rice fields.

The unintended consequence of dams

The story begins with a series of dams built along the Senegal River in the 1980s. Before the dams, there wasn't enough water to support rice farming during the dry season. After they were built, rice farming flourished. But the dams had a major unintended consequence: a surge in schistosomiasis, a disease caused by a parasitic worm that spends part of its life inside freshwater snails. The dams created more water, and thus more habitat for the snails. But they also cut off the migration route of a key predator: prawns. These large, fierce snail-eaters had kept snail numbers in check. With fewer prawns, more snails meant more of the parasite, which burrows through the skin of farmers wading in the water. The region now has among the highest burdens of schistosomiasis anywhere. Farmers li