is schistosoma mansoni replacing schistosoma haematobium in the fayoum? | schistosoma mansoni is progressively replacing s. haematobium along the nile river in egypt. this change has occurred in the past 15-20 years following construction of the aswan high dam in the 1960s. the cause is a shift in relative abundance of the snail vectors biomphalaria alexandrina and bulinus truncatus. biomphalaria is increasing while the latter has disappeared from a village in the fayoum where formerly only schistosomiasis haematobia was endemic. a cross-sectional household survey in ... | 1993 | 8279637 |