2Fasciola 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.
3Fasciola hepatica adult Morphological characteristics2-3 cm.Has conical projectionOral and ventral sucker.Pharynx.Branched caecum.Coiled uterusGenital formula : O ( ovary)T ( Testis)
5egg capsule with emerging miracidium of Fasciola hepatica
6Life cycleThe 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.
8Pathology and clinical symptoms. Most of the damage results from worms are migrating through the liver parenchyma feeding on liver cells and bloodWorms in the bile ducts cause inflammation and edemThe triad of fever, hepatomegaly, and eosinophilia.Symptoms and signs are associated with biliary obstructionAcute epigastric pain, and jaundice are common.
9diagnosisLaboratory diagnosis: finding large operculated eggs in the feces.
11Fasciolopsis 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.
12Fasciolopsis buski adult Morphological characteristics2-7x cm.Oral and ventral sucker.Esophagus .Unbranched caecum.Coiled uterus.Branched ovary.Branched Testes.Genital formula : O ( ovary)T ( Testis)
13This photo is to compare the sizes of Fasciolopsis buski (left) and Fasciola hepatica (right)
14Fasciolopsis buski Eggs Unembyonated.Thin egg shell.Inconspicuous. operculum.X um
16Clinical features Laboratory diagnosis: 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.
18Paragonimus 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.
19morphology 7 – 12 x 4 – 6 mm. Oral & Ventral Suckers Unbranched caecum.Pharynx.Coiled Uterus ( black color)Genital formula: OT T
24Pathology: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.
25DIAGNOSISbased 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