Exposure of Caged <i>Biomphalaria glabrata</i> (Say) to Investigate Dispersion of Miracidia of <i>Schistosoma mansoni</i> Sambon in Outdoor Habitats in St. Lucia

Abstract

1. Laboratory studies showed two types of cages to be suitable for exposing uninfected B. glabrata in field habitats as a means of locating S. mansoni miracidial infestations. 2. Tests conducted in tanks under simulated field conditions showed that miracidia moved away from the point of inoculation in non-random fashion and congregated at the margins of the tanks. 3. In a natural habitat, miracidia located and infected caged snails at distances of 33 cm vertically and 106·7 cm horizontally. 4. The pattern of infection was similar in the simulated field and field experiments, but field infection rates were lower. 5. For transmission studies in field habitats, caged laboratorybred snails should be placed at the margin of the habitat to ensure the maximum snail-miracidium interaction.