Medical Microbiology

Platyhelmintha(syn.Platyhelminthes) 547

cum(SoutheastAsiaandthewesternPacific,especiallyChina,Indonesia,the

Philippines,butnolongerinJapan).S.intercalatumoccursfocallyincentral

andwesternAfrica,S.mekongiinLaosandCambodia.

Morphologyandlifecycle.ThevariousSchistosomaspeciescanbedifferen-

tiatedmorphologically(Table 1 0. 2 ).

Therelativelythickmaleformsategumentalfold,theventralgroove(or

canalisgynaecophorus)inwhichthethreadlikefemaleisenclosed.Themale

thusappearstobeslitlongitudinally(schizein:tosplit,soma:body)(Fig. 1 0. 3 ).

DistributionofSchistosomes

S. mansoni

b S.intercalatum

a

S. haematobium

S. japonicum

S. mekongi

b

Fig. 1 0.2 aSchistosomahematobium,S.japonicum,andS.mekongi;

bS.mansoniandS.intercalatum(accordingtoWHOTechnicalReportSeriesNo.830.

Geneva:WorldHealthOrganization; 1 993).

10

Kayser, Medical Microbiology © 2005 Thieme