River prawns can be an effective weapon in the fight against the deadly parasitic disease, schistosomiasis. Stanford University researchers say that is because the 30-centimeter long crustaceans prey on parasite-infected snails, but do not transmit the disease themselves.
Schistosomiasis infects about 230 million people, mostly in Africa. They pick up the parasite when they go into a river to bathe or do laundry. The only treatment is a costly drug that is not widely available.
An international research team stocked a river in Senegal with prawns, which, in addition to eating the parasite-infected snails, provide a source of marketable protein-rich food. After 18 months, the researchers found 80 percent fewer infected snails and the burden of disease in a nearby village lower by half.
In reporting their study in the Proceedings of the National Academy of Sciences, the researchers say this approach has four major benefits: controlling disease, restoring biodiversity, alleviating poverty and improving nutrition.