Liver Flukes (Fasciola hepatica)

• common parasite of herbivorous animals worldwide

• human infection reported from cattle-raising countries

• leaf-like worm

• Body: anterior conical part, shoulders converging lateral borders

Parasite: Fasciola hepatica

Disease: Fascioliasis

Habitat: bile ducts of herbivorous animals and occasionally human

Definitive host: Human

Intermediate host: snail

Reservoir hosts: herbivorous animals such as cattle

Infective stage: encysted metacercariae

Mode of infection: ingestion of encysted metacercariae; either eaten on raw or undercooked vegetables or drunk with water.

Clinical Picture

• irregular fever

• indigestion

• vomiting

• biliary colic

• jaundice (due to the inflammation of bile duct and gallbladder)

• pain in the upper right hypochondrium with enlarged tender liver

• anemia

• high eosinophilia (up to 60% - 80%)

Ectopic Fascioliasis

Adult fasciola in abnormal sites when metacercariae enter the circulation and are distributed all over the body.

Halzoun (parasitic pharyngitis)

A clinical condition which occurs when eating infected raw liver of sheep.

• living fasciola worms attach to the pharyngeal mucosa by its suckers

• inflammation and edema occur

  • dyspnea or suffocation can also occur

Diagnosis

• diagnostic stage: egg

Laboratory

• detection of fasciola eggs in stool

• serological tests to detect specific antibodies

  • where no eggs pass in stool

  • particularly important:

    • during the early migratory stage of the disease

    • in ectopic infection

• Eosinophilia

Treatment

1. Triclabendazole

   • drug of choice

   • acts on immature and adult worms

2. Bithionol

Prevention and Control

1. Mass treatment of infected animal resevoirs

2. Snail eradication

   • most frequently used approach

3. Proper washing or cooking of aquatic vegetation

4. Pure filtered water supply