Date amended:
Statements of Principles
Current RMA Instruments
Reasonable Hypothesis SOP
61 of 2019
Balance of Probabilities SOP
62 of 2019
Changes from previous Instruments


ICD Coding
  • ICD-9-CM Codes: 120
  • ICD-10-AM Codes: B65
Brief description

Schistosomiasis is a parasitic disease caused by flukes (flatworms) of the genus Schistosoma.  It is a common chronic disease particularly in Asia, Africa and South America.  It may present as an acute infection, particularly in visitors to an endemic area.  It is often subclinical or only mildly symptomatic.  Exposure is via skin contact with contaminated fresh water.  The chronic form affects the intestinal tract or genitourinary tract. The acute illness may present with fever, itch, muscle and joint pain, dry cough, diarrhea, abdominal pain, and headache.

Confirming the diagnosis

The diagnosis may be suspected based on clinical grounds and travel history, but is usually established by microscopic identification of eggs in stool or urine.

The relevant medical specialist is an infectious diseases physician.

Additional diagnoses covered by SOP
  • Bilharzia
  • Bilharziosis
  • Katayama fever
Clinical onset

Most infected individuals do not develop symptomatic illness.  The acute illness, if it develops, typically commences 3 to 8 weeks after infection.  Chronic infection is unlikely in a person with brief exposure, such as a visitor to an endemic area, but may develop in a person with ongoing exposure.  The chronic form usually develops insidiously and may not become clinically apparent for months and up to several years after exposure.

Clinical worsening

The only SOP worsening factor is for inability to obtain appropriate clinical management.  Acute infection is typically treated with corticsteroids and then praziquantel once symptoms have subsided. Praziquantel is also the usual treatment for chronic infection.