Schistosoma

haematobium, intercalatum,japonicum, mansoni

Schistosomiasis or Bilharziasis

• Intestinal and urinary schistosomiasis.• Snail-mediated: snails living on waterplants.• Water contaminated by faeces or urine.

Courtesy Peters W. & Gilles H.M.Courtesy Peters W. & Gilles H.M.

Bulinus (Physopsis) africanus This snail is the intermediate host of Schistosoma

haematobium in Congo (Mayumbe, 1972).

1 cm

Biomphalaria (Planorbis) camerounensis

This snail is the intermediate host of Schistosoma mansoni in Congo (Mayumbe, 1972).

1 cm

Courtesy CDC

Cercaria S. mansoni

Schistosoma haematobium Egg, red and white blood cells in urinary sediment.

Note the small terminal spine and the mature miracidium. Very large egg: 150 μm (Unstained).

Schistosoma haematobium Egg in urinary sediment. Note the small terminal spine

and the mature miracidium. Very large egg: 150 μm (Unstained).

Schistosoma intercalatum Egg in faeces. Very elongated egg with a prominent

terminal spine. Very large egg: 140 to 240 μm (Unstained).

Schistosoma japonicum Egg in stool. The shape is round to ovoid. The shell shows a light depression with a small spine in the form

of a hooklet. Length: 70 to 100 μm (Unstained).

Schistosoma japonicumSchistosoma japonicum egg, and its vestigial spine

(arrow) taken from a liver tissue biopsy.

Courtesy CDC

Schistosoma mansoni Very large egg (about 150 μm ) in stool, with a typical

lateral spine and a miracidium (Unstained).

Schistosoma mansoni Very large egg (about 150 μm) in stool, with a typical

lateral spine and a miracidium (Unstained).

Schistosoma mansoni Very large egg in stool, with a typical spine, less

visible because it is not fully in lateral position (Unstained).

Katayama syndrome

• Acute schistosomiasis.• In uninfected persons 2-8 weeks after exposure to

S. japonicum or (S. mansoni).• Fever and several other symptoms during a few

weeks; death may occur with heavy infections.• Eosinophilia.

Maguire J.H. 2010.

Swimmer’s itch or Schistosomal dermatitis (cercarial dermatitis, clam

digger’s itch)• Due to cercaria of avian schistosmes (commonly

Trichobilharzia).• Cercaria in the skin (almost limited to the skin).• Freshwater lakes of the northern US; many areas

of the world. Saltwater (clam digger’s itch).• No specific anthelmintic therapy.

Nash T.E. 2010. In Mandell et al.