Flukes

Question 1

Clonorchis sinensis

Answer 1

Long flat shape

Encysts on scales or in flesh of freshwater fish, then undercooked fish is eaten by humans

Question 2

Paragonimus westermani

Answer 2

Rarely found in the US, from eating raw crayfish

Once ingested they travel though intestine and peritoneum into the lung

Patients may cough up the eggs, appearing as brown spots in the sputum

Question 3

Fasciolopsis buski

Answer 3

Eggs embryonate in water, and cannot be differentiated from Fasciola eggs

Eggs only found in stool in heavy infections

Can cause allergic reactions

Cercaria encyst on Water Chestnuts which are eaten by humans

Question 4

Schistosoma japonicum

Answer 4

Eggs contain fully developed miracidium, which can travel through circulation and severe complications Lodge in venules draining into small intestine

Question 5

Schistosoma characteristics

Answer 5

Cercaria have forked tails they use to burrow into the skin of their host; those that cannot infect humans get stuck in the skin and cause a rash until they die off

Eggs are the only things since in infected persons, no adults

Males and females twine together until the female leaves to lay eggs in the veins; the male has a gynecophoral groove for this

Males also have spiny projections to help them stay in the vessel

Question 6

Miracidial hatching test

Answer 6

Fresh sample filtered and placed in water, causing viable eggs to hatch

The container is kept dark except for the top, where the miracidium will be drawn to

Question 7

Destinations of S. Mansoni and S. Haematobium

Answer 7

Mansoni: veins draining to large intestine

Haematobium: venous plexus of bladder (causes bleeding from penetration of bladder wall)

Question 8

Fasciola hepatica

Answer 8

Found in/on sheep/goats/cattle and watercress

Eggs travel to biliary ducts

Acute: immature forms in ducts

Chronic: mature forms in ducts

False Fasciola: eggs in stool from recent consumption of a liver contaminated with F. hepatica

Question 9

Basic Fluke Anatomy

Answer 9

Have a Ventral and Oral sucker for attachment

Use Tegumemt for nutrient absorption

Use same pore for intake of food and excretion of waste

Most need 2 intermediate hosts

Question 10

C. sinensis Life Cycle

Answer 10

Question 11

P. westermani Life Cycle

Answer 11

Question 12

F. buski Life Cycle

Answer 12

Question 13

S. japonicum Life Cycle

Answer 13

Question 14

F. hepatica Life Cycle

Answer 14

Question 15

Answer 15

Clonorchis sinensis Trematode

Question 16

Answer 16

C. sinensis Egg

Question 17

Answer 17

P. westermani Egg

Question 18

Answer 18

F. buski Egg

Question 19

Answer 19

S. japonicum Egg

Question 20

Answer 20

F. hepatica Egg