||Life-history traits indicate local adaptation of the schistosome parasite, Schistosoma mansoni, to its snail host, Biomphalaria pfeifferi
||The digenean trematode Schistosoma mansoni causes schistosomiasis (Bilharziasis), a significant human disease
especially in sub-Saharan Africa.We tested local adaptation of this parasite to its intermediate host, the freshwater snail Biomphalaria pfeifferi, by exposure of S. mansoni to B. pfeifferi from one sympatric and four allopatric populations and measurement of life-history traits of both species over time. The pre-patent period, infection rate, and cercarial production of the parasite were determined, and the shell diameter, fecundity, and survival of the snail host were determined. The results provide evidence for local adaptation of S.mansoni to itssympatric snail host: the pre-patent period wasthe shortest, the cercarial productionwasmoderate and accompanied by a higher survival rate, the growth was greater during the pre-patent period, and the fecundity was greater during the pre-patent period. The greater growth and fecundity of sympatric B. pfeifferi suggests the presence of growth and fecundity compensation. These fitness traits are relevant to energy allocation of the snail host and to the transmission strategy of the schistosome parasite.
||Schistosoma mansoni, Biomphalaria pfeifferi, Local adaptation, Life-history traits, Growth compensation, Fecundity compensation
||501 - 507