Recommended
More Related Content
Similar to Lung and Liver Flukes - Parasitology Group 3 Presentation.pdf
Similar to Lung and Liver Flukes - Parasitology Group 3 Presentation.pdf (20)
Recently uploaded
Recently uploaded (20)
Lung and Liver Flukes - Parasitology Group 3 Presentation.pdf
- 1. TREMATODES (FLUKES) BY GROUP THREE
- 2. General Characteristics • Trematodes • Flat worms or flukes • Have two or more hosts • Fresh Water Snails are first intermediate hosts • Eggs • Some are embryonated • Some contain miracidium • Operculated except schistosomes. • Miracidium • Embryonated part which • infect snails • Cercariae • Miracidia infected snails go through a process to produce cercariae • Cercariae are released by snails into fresh water • They swim until they find the next host • They may excyst to form metacercaria • Other Characteristics • Hermaphrodites except Schistosomes • Treated with praziquantel 06/24/2023 2
- 3. The trematodes • Intestinal Flukes • Fasciolopsis buski • Liver Flukes • Fasciola hepatica (Sheep liver fluke) • Clonorchis sinensis (Chinese liver fluke) • Opisthorchis felineus (Cat liver fluke) • Dicrocoelium dendriticum (Lancet liver fluke) • Lung Flukes • Paragonimus westermani • Blood Flukes • Schistosoma mansoni • Schistosoma haematobium • Schistosoma japonicum • Schistosoma intercalatum 06/24/2023 3
- 5. Fasciola hepatica (Sheep Liver Fluke) • Fasciola hepatica causes a disease known as fascioliasis • It is distributed worldwide and is common in sheep rearing areas of the world • Man is infected accidentally or become an accidental definitive host by eating fresh water plants (e.g. watercress ) that are infected with the Fasciola hepatica metacercariae • Intermediate hosts of F. hepatica are air-breathing freshwater snails from the family Lymnaeidae. Galba truncatula is the main snail host in Europe, partly in Asia, Africa and South America 06/24/2023 5
- 6. Morphology • Adults Fasciola hepatica are flattened, leaf-shaped and brown coloured, having a cone-shaped anterior protrusion and rounded posterior end • The fluke measures 2.5 cm to 3 cm in length and 1.5 cm in breadth • They have an anterior and a ventral suckers • The adult worms are smaller in sizes than Fasciolopsis buski 06/24/2023 6
- 7. Contd…. 06/24/2023 7 • Egg: The eggs are large, ovoid and bile-stained and have a small, but distinct operculum • They measure 130-150 µm by 63-90 µm • These are unembryonated when freshly passed • The eggs are excreted in the bile into the duodenum, from where they are excreted out in the faeces • Further development of the eggs take place only in water
- 9. 06/24/2023 9 LIFE CYCLE OF FASCIOLA
- 10. Clinical Manifestation • Human Fasciola hepatica infection is manifested by headache, chills, fever and right upper quadrant pain • Hepatomegaly, jaundice, diarrhoea and anemia may occur in severe infections • Hepatic, biliary cirrhosis is a late complication Diagnosis • Stool R/E • Wet preparation • Concentration technique Treatment • Praziquantel 06/24/2023 10 Prevention • Can be prevented by not eating • Wild aquatic vegetables (watercress) • Raw sheep
- 11. Clonorchis sinensis (Chinese or oriental liver fluke) • It infects fish-eating mammals including humans • In humans, it infects the common bile duct and gall bladder, feeding on bile • The fluke passes its life cycle in three different hosts: freshwater snail (Paraforssarulus manchouricus) as first intermediate host, freshwater fish as second intermediate host, and mammals as definitive host 06/24/2023 11
- 12. Morphology • Eggs • Clonorchis sinensis eggs are small, ranging in size from 27 to 35 µm by 11 to 20 µm. • The eggs are oval shaped with a convex operculum that rests on visible “shoulders” at the smaller end of the egg. • At the opposite (abopercular) end, a small knob or hook-like protrusion is often visible. • The miracidium is visible inside the egg. Eggs of C. sinensis are highly morphologically similar to Opisthorchis spp. 06/24/2023 12
- 13. Contd…. • Adult • Clonorchis sinensis adults are flattened, lance shaped, and measure approximately 10 to 25 mm long by 3 to 5 mm wide. • The oral and ventral suckers (acetabulum) are relatively small. • The two testes are located posterior to the ovary, and are highly branched–a feature which separates it from the related Opisthorchis spp. (rounded testes). • Reside in the biliary passages of the liver of the definitive host. 06/24/2023 13
- 15. 06/24/2023 15 LIFE CYCLE OF CLONORCHIS
- 16. Clinical Manifestation • Mostly asymptomatic • Pathological manifestations result from inflammation and intermittent obstruction of the biliary ducts • The acute phase consist of abdominal pain, nausea and diarrhoea • Chronic phase consist of fatigue, abdominal discomfort, anorexia, weight loss, diarrhoea and jaundice • The pathology of long-standing infections consist of bile stasis, obstruction, bacterial infections, inflammation, periductal fibrosis and hyperplasia • Development of cholangiocarcinoma is progressive Diagnosis • Stool R/E Treatment • Praziquantel 06/24/2023 16 Prevention • Adequate cooking of fish • Proper disposal of human waste
- 18. Paragonimus westermani • Paragonimus westermani and other Paragonimus species are lung flukes causing paragonimiasis. • Human infections are most common in West Africa, the Far East and certain regions of Central and South America • Less frequent, but more serious cases of paragonimiasis occur when the parasite travels to the central nervous system. • Humans become infected following ingestion of raw or poorly cooked fresh water crab – meat or cray – fish, the flesh of which contains the encysted metacercariae 06/24/2023 18
- 19. Morphology • Egg is ovoid, relative thick-shell golden brown in colour and has a flattened operculum at the large end and the opposite (abopercular) end is thickened • Adult worm – reddish brown in colour live in the cavities in the lungs Egg Adult 06/24/2023 19
- 20. 06/24/2023 20 LIFE CYCLE OF PARAGONIMUS
- 21. Clinical Manifestation • P. westermani infection of the lungs causes cough, blood-stained sputum, chest pain and night sweats. These symptoms (and the chest X-ray) may mimic tuberculosis • Adult worms of P. westermani occasionally invade sites outside the lung, e.g. lymph glands, subcutaneous tissue, eyes, testes and brain causing severe disease Diagnosis • Wet mount preparation of sputum and stool observed under the microscope Treatment • Praziquantel Prevention • Adequate cooking of crab • Proper disposal of human waste 06/24/2023 21
- 22. SUMMARY Fasciola hepatica • Disease • Fasciolosis /Fascioliasis • Mode of transmission: • Ingestion of aquatic plants (e.g. water cress) or raw sheep liver infected with metacercariae • Intermediate hosts • fresh water snail of genus Lymnae • Aquatic vegetations and water cress • Reservoir • Sheep, cattle, rabbits • Features of egg • Large, ovoid with a small but distinct operculum • Features of adult • Flattened and leaf-like, having a cone shaped anterior protrusion. • Life cycle: • Egg Miracidia Sporocyst Rediae Cercariae Metacercariae Adult fluke 06/24/2023 22 • Habitat • Liver (bile tract) • Infective stage • Metacercariae • Diagnostic stage • Unembryonated eggs • Specimen for laboratory diagnosis • Sputum, urine and faeces
- 23. SUMMARY CONTINUED. Clonorchis sinensis • Disease • Clonorchiasis • Mode of transmission: • Via feco-oral route • By eating raw or undercooked infected fish • Intermediate hosts • Freshwater snail (Paraforssarulus manchouricus) • freshwater fish • Features of egg • Oval shaped with a convex operculum (Ant. end) • Abopercular end, a small knob or hook-like protrusion (Post. end) • Features of adult • Narrow and flattened dorsal-ventrally • Tapered at the anterior end and rounded at the posterior end • Life cycle: • Egg Miracidia Sporocyst Rediae Cercariae Metacercariae Adult fluke 06/24/2023 23 • Habitat • Distal biliary passages and pancreatic duct • Infective stage • Metacercariae • Diagnostic stage • Embryonated eggs • Specimen for laboratory diagnosis • Sputum, urine and faeces
- 24. SUMMARY CONTINUED. Paragonimus westermani • Disease • Paragonimiasis • Mode of transmission: • Via feco-oral route • By eating raw or undercooked crab meat or crayfish • Intermediate hosts • Freshwater snail as first intermediate host • Freshwater crustacean as second intermediate host • Features of egg • Ovoid, relative thick-shell golden brown in colour • Flattened operculum at the large end • Opposite (abopercular) end is thickened • Features of adult • Reddish brown in colour • Similar in size and appearance to a coffee bean • Life cycle: • Egg Miracidia Sporocyst Rediae Cercariae Metacercariae Adult fluke 06/24/2023 24 • Habitat • Parenchyma of the lungs • Infective stage • Metacercariae • Diagnostic stage • Unembryonated eggs • Specimen for laboratory diagnosis • Sputum, faeces