Schistosomiasis is a disease transmitted by snails, responsible for chronic illness of many millions of the world's poorest people, mainly in Africa. This project tests the efficacy of RNAi, a targeted genetic weapon, to kill the snails and thus curtail the spread of the disease. RNAi acts only on specific gene sequences, making it environmentally benign and preventing the evolution of resistance in snail populations. Importantly, this snail-killing material would be very cheap to produce.