[A soap to fight schistosomiasis: a field intervention worth considering?]

An experiment was carried out in 1985-87 against schistosomiasis using products neutralizing the intermediate stages of schistosomes. In the laboratory, it had been shown that lauryl betaines, amphoteric substances, used for children's shampoos, quickly immobilized miracidiums and cercariae. Studies in Niger in field conditions with water laden with organic matter gave similar results. This surfactant can be incorporated into ordinary soaps at a dose of 5% without changing their characteristics. Betaine soaps were put on sale in ordinary commercial channels in Niger then in Côte d'Ivoire, in hyperendemic villages for Schistosoma haematobium. Betaines diffused without external intervention into the water used by populations for washing. The soaps were well accepted by these populations. However, after one year, the results in tested villages compared to control ones were unclear on the dynamics of urinary schistosomiasis in terms of prevalence and oviuria. Anti-schistosome treatment seems necessary at the start of the procedure. The use of soap by populations needed to be measured. In conclusion, this promising laboratory action deserves to be evaluated again in the field, in addition to health education and systematic treatment actions.