Schistosomiasis

Dr. Bipin Kumar

Assistant Professor

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Department of Veterinary Medicine

Bihar Veterinary College, Patna

(Bihar Animal Sciences University, Patna)

Trematodes �Schistosomes: Blood flukes

Family: Schistosomatidae

Genus: Schistosoma

For animals(ruminant & horses) : Sch. bovis, sch. Mattheei, sch. Spindale, sch. nasalis, Sch. margrebowiei

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Disease : Bilharziasis or Schistosomiasis

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• Introduction
• Fascioliasis is called as liver fluke disease or liver rot
• Fasciola hepatica: Mostly found in temperate and cooler area of high altitude in tropical and subtropical countries
• Fasciola gigantica: Mostly in tropical countries
• Morphology
• Broad-leaf like body

Host affected

• Natural host: Cattle, Buffalo, Sheep, Goat and Other ruminants
• Unusual host: Horse & Man

Location

• Immature flukes: Small intestine, peritoneal cavity and liver parenchyma
• Mature flukes: Bile duct

• S. nasale inhabits blood vessels of the nasal mucosa and causes "snoring disease" in cattle.
• symptomless in buffaloes though extruding its eggs in nasal discharge.
• intermediate host is a freshwater snail Indoplanorbis exustus.

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Life Cycle, Transmission, and Epidemiology�

• Schistosomes live in the mesenteric and hepatic veins (except for S nasale, nasal veins).
• Eggs passed in the feces releases miracidia, which invade suitable water snails and develop through primary and secondary sporocysts to become cercariae.
• When fully mature, the cercariae leave the snail and swim freely in the water, where they remain viable for several hours.
• Animals are infected with cercariae through skin, although infection may be acquired orally while animals are drinking.
• During penetration, cercariae develop into schistosomula, which are transported via the lymph and blood to their predilection sites.

Signs and symptoms�

Visceral Schistosomiasis:

• The disease is characterized by diarrhea, weight loss, anemia, hypoalbuminemia, hyperglobulinemia,
• Severe eosinophilia that develop after the onset of egg excretion.
• Severely affected animals deteriorate rapidly and usually die within a few months of infection.
• Less heavily infected develop chronic disease with growth retardation.

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Nasal Schistosomiasis

• cauliflower-like growth or granuloma in the nasal cavity.
• "snoring" sound and profuse mucopurulent.

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Diagnosis

• By eggs in the faeces.
• Microscopic examination of the mesenteric veins for the presence of adult worms.
• Microscopic examination of scrapings of the intestinal mucosa or of crushed liver tissue (both for eggs).
• Eggs of S bovis, S curassoni, and S mattheei are spindle-shaped.
• Eggs of S nasale are boomerang-shaped while oval type of S japonicum.

Treatment&Control

• Anthiomaline was the drug of choice, but this leads to relapse of the symptoms after two months of the treatment.
•  Praziquantel@25mg/kg proved better than any other drug.
•  Triclabendazole @10mg/kg.
• Snail control.

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