Schistosomiasis is a disease caused by five species of the parasitic genus Schistosoma

Humans are infected with schistosomes after contact with freshwater containing cercariae released by infected snails

Symptoms & Signs 

Schistosomiasis has three stages of clinical symptomatology corresponding to the life cycle of the parasite in the human host 

Stage 1: Cercarial Dermatitis (“Swimmer’s Itch”)

The first stage is characterized by a very itchy maculopapular rash which occurs at the time of penetration 

Stage 2: Acute schistosomiasis (Katayama syndrome)

The second stage is characterized by a serum sickness like syndrome with elevated levels of immunoglobulin E and eosinophilia. 

-Fever,chills, myalgias, headache, cough, sweating, lymphadenopathy, hepatosplenomegaly, diarrhea, abdominal pain, and pulmonary infiltrates 

Stage 3: Chronic schistosomiasis

The third, chronic stage is characterized by granulomatous reactions to egg deposition in the intestine, liver, bladder, lung and CNS 

-Chronic diarrhea, abdominal pain, blood loss, portal hypertension, splenomegaly, bleeding esophageal varices, pulmonary hypertension, right-sided congestive heart failure, transverse myelitis, hematuria, bladder obstruction, hydroureter, and hydronephrosis


Diagnostic methods: Detection of schistosome eggs in stool or urine, ELISA, biopsy of the rectum, colon, liver or bladder 

-Eggs of Schistosoma haematobium possess a characteristic terminal spine


The drug of choice for treatment of schistosomiasis is praziquantel

Chemoprophylaxis with artemether has shown efficacy 

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