| seasonal population densities of snails transmitting urinary and intestinal schistosomiasis in lusaka, zambia. | the two molluscan intermediate hosts of s. haematobium schistosomiasis: bulinus africanus and bulinus globosus, were found most commonly in habitats that retained water for a substantial part of the year rather than in temporary rain-filled pools. biomphalaria pfeifferi which transmits s. mansoni were found principally in streams and impoundments like dams but scarce in rivers. in a permanent habitat, the peak density of snails was between the warm, dry months of august and september while in a ... | 1975 | 1169833 |