Mating interactions between Schistosoma haematobium and S-mansoni

Schistosoma haematobium and S. mansoni are two medically important schistos omes, commonly occurring sympatrically in Africa and so potentially able to infect the same human host. Experiments were designed to study the mating behaviour of these two species in mixed infections in hamsters. Analysis of the data obtained showed that both heterospecific and homospecific Fairs r eadily form. No significant difference was seen between the two species in their ability in forming Fairs, however, S. mansoni showed a greater homosp ecific mate preference. Analysis of the data using the Mantel-Haenszel test suggests that mating competition does occur between S. haematobium and S, mansoni, the former being the more dominant species. Both species appeared to be able to change mate, with S. haematobium showing a greater ability in taking S. mansoni females away from S. mansoni males when introduced into a pre-established S, mansoni infection highlighting the competitiveness of S. haematobium. The significance of the results is discussed in relation to the epidemiological consequences occurring in Senegal, and other areas whe re both species are sympatric.