SCHISTOSOMIASIS

• Schistosomiasis


  Slowly progressive disease caused by blood flukes
• Other terms for schistosomiasis

  • Bilharziasis
  • Snail Fever
• Causative agents


  • Schistosoma japonicum - endemic in the Philippines and China
  • Schistosoma mansoni - South America, the Caribbean, Africa and countries of the Arab Middle East
  • Schistosoma haematobium - Africa and the Middle East
• Source of infection


  Stool and urine of infected persons or animals
• Mode of transmission


  1. Ingestion of contaminated water

  2. Penetration through the skin pores
• Intermediary host


  Oncomelania hupensis quadrasi
• Incubation period


  At least 2 months
• Clinical manifestations - 1st stage

  Pruritic rash known as "swimmers itch" occurs 24 hours after penetration of cercariae in the skin
• Clinical manifestations - 2nd stage

  1. Bloody mucoid stools (on and off for weeks)

  2. Katayama Fever - fever, headache, cough, chills and sweating, lymphadenopathy and hepatosplenomegaly
• Clinical manifestations - 3rd (chronic) stage

  1. Granulomatous reactions to egg deposition in the intestine, liver, bladder

  2. Inflammation of the liver, icteric and jaundice

  3. Bulging of the abdomen, enlargement of the spleen

  4. Brain affected that caused epilepsy

  5. Eggs deposited in bladder wall, leading to hematuria, bladder obstruction, hydronephrosis and recurrent urinary tract infection

  6. Pale and marked muscle wasting
• Complications


  • Liver cirrhosis and portal hypertension
  • Bleeding esophageal varices
  • Bladder cancer
  • Pulmonary hypertension
  • Heart failure
  • Ascites
  • Renal failure
  • Cerebral schistosomiasis
• Diagnostic procedures


  • Fecalysis
  • Liver and rectal biopsy
  • ELISA
  • Circumoval precipitation test (COPT) - confirmatory test
• Management


  1. Drug of choice: PRAZIQUANTEL for 6 months - 1 tab 2x a day for 1st 3 mos, 1 tab a day for next 3 mos

  2. Alternative: Ovamniquine
• Nursing interventions


  • Skin care
  • Provide comfort
  • Proper nutrition
• Prevention and control


  • Reduce snail density
  • Molluscicides
  • Stream cleaning vegetation (expose the snails to sunlight)
  • Proper waste disposal
  • Control of stray animals
  • Safe and adequate water supply for bathing, laundering and drinking
  • Foot bridges over snail-infested streams
  • Health education about mode of transmission and prevention