Schistosoma, blood fluke
Schistosoma species are causative agents of a tropical disease schistosomiasis or bilharzia. Millions of people are infected worldwide by three main species: S. mansoni, S. japonicum, and S. haematobium
Of the ~2700 genera of Digenean parasites, the 13 that comprise the Schistosomatidae are different in the following ways:
they have two rather than three hosts
they are dioecious (having female and male reproductive organs in separate individuals)
they infect their hosts by directly penetrating the body surface, rather than being eaten
they are intravascular parasites (live inside blood vessels)
No routine laboratory techniques were developed so far for culturing schistosomes through their complete life cycle in vitro as well as for expressing transgenes for targeted gene silencing and other purposes. Also, there are no schistosome cell lines. Therefore, analysis of schistosome-host interactions are very challenging and is confined mostly to traditional parasitological techniques.
Schistosoma mansoni
General information
Life cycle
Schistosoma japonicum
General information
Life cycle
Schistosoma haematobium (not yet represented here)
Pathologies
References
cellular organisms - Eukaryota - Fungi/Metazoa group - Metazoa - Eumetazoa - Bilateria - Acoelomata - Platyhelminthes - Trematoda - Digenea - Strigeidida - Schistosomatoidea - Schistosomatidae - Schistosoma
Schistosoma mansoni
General information
Schistosoma mansoni is digenic trematode ("digenic" means that its lifecycle includes two hosts - definitive and intermediate) of the superfamily Schistosomatoidea.
Intermediate host of S. mansoni are snails of the genus Biomphalaria (Planorbidae family).
S. mansoni occurs in Africa, Madagascar, parts of South America (such as Venezuela and Brazil), Puerto Rico and the West Indies.
S. mansoni is found in rodents and primates but primary target of the infection are humans.
Life cycle of Schistosoma mansoni