Fasciola hepatica sheep liver fluke liver fluke. Fasciola hepatica Common name: The sheep liver...
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Transcript of Fasciola hepatica sheep liver fluke liver fluke. Fasciola hepatica Common name: The sheep liver...
Fasciola hepaticaFasciola hepatica sheep liver flukesheep liver fluke
liver flukeliver fluke
Fasciola hepatica• Common name: The sheep liver fluke• Habitat: Bile duct of liver.• Route of infection: Man eat aquatic plants with
encysted metacercariae.• Definitive host: Usual host sheep, infects liver of
various mammals, including humans.• Intermediate host: Fresh water snails.• Infective stage: Encysted metacercariae on
vegetations.• Diagnostic stage: Eggs in stool specimen.• Disease: Fascioliasis.
Fasciola hepatica adult
Morphological characteristics• 2-3 cm.• Has conical projection• Oral and ventral sucker.• Pharynx.• Branched caecum.• Coiled uterus• Genital formula : O ( ovary) T ( Testis) T ( Testis)
Fasciola hepatica Eggs
• Unembyonated.• Thin egg shell.• operculated. • 130-150 X 63-90 um.• Diagnostic stage
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egg capsule with emerging miracidium of Fasciola hepatica
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Life cycle
• The parasite browses on liver tissue for a period of up to 5-6 weeks and eventually finds its way to the bile duct where it matures into an adult and begins to produce eggs.
• Up to 25,000 eggs per day per fluke can be produced, and in a light infection, up to 500,000 eggs per day can be deposited onto pasture by a single sheep.
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Pathology and clinical symptoms.
• Most of the damage results from worms are migrating through the liver parenchyma feeding on liver cells and blood
• Worms in the bile ducts cause inflammation and edem• The triad of fever, hepatomegaly, and eosinophilia.• Symptoms and signs are associated with biliary obstruction • Acute epigastric pain, and jaundice are common.
diagnosis
Laboratory diagnosis: finding large operculated eggs in the feces.
Intestinal fluke
Fasciolopsis buskiFasciolopsis buski
Fasciolopsis buski• Common name: The large intestinal fluke• Habitat: Lumen of small intestine.• Route of infection: Man eat uncooked plants with encysted
metacercariae.• Definitive host: Mainly human, other hosts; pigs and dogs.• Intermediate host: Fresh water snails.• Infective stage: Encysted metacercariae on vegetations.• Diagnostic stage: Eggs in stool specimen.• Disease: Fasciolopiasis.
Fasciolopsis buski adult
Morphological characteristics• 2-7x 0.5-2 cm.• Oral and ventral sucker.• Esophagus .• Unbranched caecum.• Coiled uterus.• Branched ovary.• Branched Testes.• Genital formula : O ( ovary) T ( Testis) T ( Testis)
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This photo is to compare the sizes of Fasciolopsis buski
(left) and Fasciola hepatica (right)
Fasciolopsis buski Eggs
• Unembyonated.• Thin egg shell.• Inconspicuous.
operculum. • 130-150 X 63-90 um
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Clinical features
• Most infections are light and asymptomatic. In heavier infections, symptoms include diarrhea, abdominal pain, fever, ascites, and intestinal obstruction.
Laboratory diagnosis:operculated eggs and some times the adults are
found in the feces.
Lung Fluke
Paragonimus westermaniParagonimus westermani
Paragonimus westermani
• Common name: The Lung Fluke.• Habitat: Encapsulated in Lungs.• Definitive host: Human, also other mammals.• First intermediate host: Water snail.• Second intermediate host: Crustaceans,Crabs.• Infective stage: Encysted metacercariae.• Diagnostic stage: Eggs in sputum or feces.• Disease: Paragonimiasis.
morphology
• 7 – 12 x 4 – 6 mm.• Oral & Ventral Suckers• Unbranched caecum.• Pharynx.• Coiled Uterus ( black color)• Genital formula: O T T
Paragonimus westermani
Paragonimus westermani Eggs
• 80-120 x 50-60 um• Large, thick, dark shell.• Prominent operculum at
the broad end.• Thick posterior end.• Unembryonated.
Egg Miracidio
RediaI Redia II
Cercarias Metacercarias
Life Stages
Paragonimus westwermani
• Pathology: Adults in lungs stimulate inflammatory response
resulting in granulomas. Movement of worms to heart or brain causes death.
• Symptoms: Chronic cough , difficulties breathing , sputum
with blood. When moves to brain, can cause blindness,
paralysis , disequilibrium , epilepsy.
DIAGNOSIS• based on detection of characteristic eggs in sputum, or
stool,• serology helpful; standard test is complement fixation
(CF) – has advantage to detect rapid decline in antibody levels