T7 - Fascioliasis

Question 1

• parasitic infection caused by two species of liver flukes Fasciola hepatica and Fasciola gigantica
• zoonotic disease and foodborne trematode infection
• primarily affect the liver and bile ducts

Answer 1

Fascioliasis

Question 2

common large liver fluke

Answer 2

Fasciola hepatica

Question 3

large liver fluke

Answer 3

Fasciola gigantica

Question 4

Life cycle of Fasciola

Answer 4

1. Unembryonated eggs passed in feces
2. Eggs embryonate in water
3. Miracidia hatch from eggs, seek out snail intermediate host
4. Miracidia penetrate snail intermediate host
5. Free-swimming cercariae encyst on aquatic vegetation
6. Metacercariae on vegetation ingested by definitive host
7. Immature flukes excyst in duodenum, penetrate intestinal wall, and migrate through liver parenchyma to biliary ducts

Question 5

mode of transmission of Fasciola

Answer 5

1. Ingestion of contaminated plants and water
2. Poor sanitation

Question 6

Pathogenesis of Fasciola:
acute phase

Answer 6

1. immature flukes cause mechanical damage to liver tissue during migration
2. results in hemorrhage, necrosis, and intense inflammation

Question 7

Pathogenesis of Fasciola:
chronic phase

Answer 7

1. adult flukes in bile ducts induce hyperplasia, fibrosis, and obstruction due to chronic inflammation
2. may lead to cirrhosis or secondary bacterial infections such as cholangitis

Question 8

Symptoms of Fascioliasis:
acute phase

Answer 8

1. fever, nausea, vomiting
2. right upper quadrant abdominal pain
3. hepatomegaly
4. skin rashes (urticaria)
5. eosinophilia

Question 9

Symptoms of Fascioliasis:
chronic phase

Answer 9

1. intermittent abdominal pain
2. jaundice
3. anemia
4. gallstones or pancreatitis

Question 10

Diagnosis for Fascioliasis

Answer 10

1. Microscopy (egg detection)
2. Serology
3. ERCP and imaging

Question 11

easy and available but late-stage detection

Answer 11

microscopy (egg detection)

Question 12

early detection but possible false positives

Answer 12

Serology

Question 13

confirms fluke presence but requires specialized equipment

Answer 13

ERCP and imaging

Question 14

Geographical distribution:
Fasciola hepatica

Answer 14

1. found on all inhabited continents
2. common in areas with sheep or cattle
3. human infections in Europe, Middle East, Latin America, Caribbean, Asia, Africa, Australia

Question 15

Geographical distribution:
Fasciola gigantica

Answer 15

1. mainly found in tropical and subtropical regions
2. intermediate forms are reported in areas where both species are endemic

Question 16

People at risk of Fascioliasis

Answer 16

1. consumers of raw aquatic plants
2. residents in endemic regions
3. agricultural workers
4. people drinking untreated water
5. veterinarians and animal handlers

Question 17

treatment for Fascioliasis

Answer 17

1. Triclabendazole
2. Nitazoxanide

Question 18

Prevention of Fascioliasis

Answer 18

1. Avoid eating raw aquatic plants
2. drink clean, treated water
3. cook animal liver properly
4. control snail populations
5. deworm livestock regularly
6. maintain proper sanitation