NAME: Fasciola hepatica, Fasciola gigantica
SYNONYM OR CROSS REFERENCE: Fascioliasis, sheep liver fluke disease, halzoun, marrara, Human Fascioliasis (HF)
CHARACTERISTICS: Trematode; relatively flat and leaf-like, fleshy, measures 20-30 mm in length by 8-13 mm wide; distinct cephalic cone gives a characteristic shouldered appearance; eggs are large (130-150 µm by 60-90 µm), ovoid and unsegmented when laid
PATHOGENICITY: Acute symptoms may persist from several weeks to months and include acute dyspepsia, anorexia, nausea, vomiting, prolonged high fever, abdominal pains and sometime hepatomegaly, hepatic tenderness and urticaria; ectopic infection sites including the lungs, intestinal wall, heart, brain, biliary duct and skin can occur; in endemic areas, acute nasopharyngitis can occur
EPIDEMIOLOGY: World wide human infections reported in sheep and cattle raising areas (in South America, Caribbean, Europe, Australia and Middle East and Asia); cases documented in USA; F. gigantica restricted to mainly Africa, western Pacific and Hawaii
HOST RANGE: Humans, sheep, cattle, snails, cattle, water buffalo, llama, emus
INFECTIOUS DOSE: Not known
MODE OF TRANSMISSION: Eating uncooked aquatic plants (such as watercress) containing encysted forms (metacercariae) of the parasite, contaminated water, eating parasitised cattle or sheep liver
INCUBATION PERIOD: Variable; depends on the dose of flukes
COMMUNICABILITY: Not directly transmitted from person-to-person
RESERVOIR: Humans are accidental hosts; infection in nature maintained by cattle, sheep and snails (Family: Lymnaeidae); cattle, water buffalo and other herbivorous mammals harbors F. gigantica
ZOONOSIS: Yes - infections acquired indirectly through cattle, sheep, water buffalo
VECTORS: Snails ( family lymnaeidae)
DRUG SUSCEPTIBILITY: Sensitive to bithionol, praziquantel, nitazoxanide, albendazole, triclabendazole (TCBZ - test for strain resistance)
DRUG RESISTANCE: TCBZ resistant striains
SUSCEPTIBILITY TO DISINFECTANTS: Sensitive to 1% sodium hypochlorite, 2% glutaraldehyde
PHYSICAL INACTIVATION: Sensitive to heat
SURVIVAL OUTSIDE HOST: Encysted form can survive for prolonged periods in the environment, resistant to drying
SURVEILLANCE: Monitor for symptoms; confirm by serology , indirect haemagglutination test (IHAI), and microscopic examination of flukes, eggs in feces
FIRST AID/TREATMENT: Administer appropriate drug therapy
IMMUNIZATION: None available
PROPHYLAXIS: None available
LABORATORY-ACQUIRED INFECTIONS: Not reported to date
SOURCES/SPECIMENS: Tissue biopsy specimens, feces, bile aspirated from duodenum
PRIMARY HAZARDS: Ingestion; accidental parenteral inoculation
SPECIAL HAZARDS: None
CONTAINMENT REQUIREMENTS: Biosafety level 2 practices and containment equipment for all activities involving the infective stages of the parasite, and potentially infectious body fluids and tissues
PROTECTIVE CLOTHING: Laboratory coat: gloves when skin contact with infectious materials is unavoidable
OTHER PRECAUTIONS: Work with this agent should be conducted in a biological safety cabinet or its equivalent
SPILLS: Allow aerosols to settle; wearing protective clothing, gently cover the spill with absorbent paper towel and apply 1% sodium hypochlorite, starting at the perimeter and working towards the center; allow sufficient contact time (30 min) before clean up
DISPOSAL: Decontaminate all wastes before disposal; steam sterilization, chemical disinfection, incineration
STORAGE: In sealed containers that are appropriately labelled
Date prepared: March, 2001
Prepared by: Office of Laboratory Security, PHAC
Although the information, opinions and recommendations contained in this Material Safety Data Sheet are compiled from sources believed to be reliable, we accept no responsibility for the accuracy, sufficiency, or reliability or for any loss or injury resulting from the use of the information. Newly discovered hazards are frequent and this information may not be completely up to date.
Copyright ©
Health Canada, 2001