All trematodes which cause infections and diseases in humans (zoonoses) require snails for their first intermediate host. Some have additional intermediate hosts such as crustaceans, fishes and frogs.

In this paper I have discussed the use of various procedures for controlling snail populations thereby reducing the population of trematodes whose cercariae penetrate the skin of man, or which are acquired by eating raw aquatic vegetation such as watercress, or which cause pathology in fish. Biological, chemical, and physical snail control techniques are discussed. The most promising molluscucides are copper compounds, Bayluscide, biocidal rubber and molluscicidal bait.