Studies on the relationship between Schistosoma and their intermediate hosts. V. The genus Bulinus and Schistosoma bovis from Iringa, Tanzania.

The relationship between an isolate of Schistosoma bovis from Iringa, Tanzania, and various species of the host snail genus Bulinus from East Africa was studied using the total cercarial production per 100 exposed snails over a period of 4 weeks following patency as an index of the compatibility. All populations of Bulinus forskalii and B. africanus tested exhibited a high level of susceptibility while the populations of B. truncatus and B. globosus tested were either refractory or of low to moderately low susceptibility. All populations of B. abyssinicus, B. canescens, B. nasutus and B. tropicus tested were refractory. It is suggested that B. africanus is the most important host snail for S. bovis in East Africa, that B. forskalii at least locally may contribute significantly to the transmission and that B. truncatus and B. globosus only play a limited role in the transmission.