1. Clonorchis Sinensis
Lida Shaygan

2. What is Clonorchis Sinensis?
Chronic infection caused by the liver fluke
Parasitic worm mm long
Lives in bile ducts of liver in humans and other mammals
Acquired by eating fresh water fish containing fluke larvae.
One of the most severe food-borne parasitic diseases in China

3. Taxonomy & Morphology Morphology Taxonomy Hermaphrodite Digenetic
Unsegmented
Leaf- shaped
Bilaterally symmetrical excretory system
Bear 2 suckers
Ventral
Oral
Oblong shaped
Flat (platyhelminthes)
relatively small
10-25 mm in length
Taxonomy
Kingdom: Animalia
Class: Platyhelminthes
Order: Trematoda
Family: Opisthorchiidae
Genus: Clonorchis
Species: Sinensis

4. MORPHOLOGY

5. Egg
oval-shaped, micrometers in length, has a thick yellow-brown shell surrounding it.
Embryonated eggs are discharged in the biliary ducts and in the stool

6. The Snail 1st Intermediate Host
Eggs are ingested by a suitable snail intermediate host
there are more than 100 species of snails that can serve as intermediate hosts. 

7. Developmental Stages
Each egg releases a miracidia , which goes through several developmental stages:

8. Metacercariae
After a short period of free-swimming time in water, cercariae come into contact and penetrate the flesh of freshwater fish, where they encyst as metacercariae

9. Adult Fluke
Metacercariae excyst in the duodenum and ascend the biliary tract
Maturation takes approximately 1 month.
The adult flukes (measuring 10 to 25 mm by 3 to 5 mm) reside in small and medium sized biliary ducts. 

10. Life Cycle Eggs passed on through feces Miracidia Sporocysts
Eggs ingested by snail
Rediae
Cercaria
Free floating cercariae encyst
Metacercaria in skin or flesh of fish
Metacercaria ingested by human host
Excyst in duodenum & adults in biliary duct

11. Life Cycle

12. Reproduction Reciprocally Inseminating Simultaneous Hermaphrodite
Polyembryonic proliferation of miricidia to metacercaria
The sporocyst and redia stages asexually reproduce.
A juvenile adult reaches the bile ducts within 4-7 hours after ingestion
It will then be one month before it is mature enough to start producing eggs.

13. Hosts 1st intermediate host: snail
2nd intermediate host: numerous freshwater fish
Hosts ingest metacerariae
Humans and animals (dogs, pigs, cats, rats)

14. Transmission Factors & Modes of Transmission
1. Eating raw fish or “porridge with raw fish”
2. Eating under-cooked small fish and shrimps
Infection due to using metacercaria-contaminated utensils or hands

15. Symptoms Asymptomatic Nonspecific symptoms
Acute phases: abdominal pain, nausea, diarrhea, and eosinophilia

16. Pathogenic Effects
Inflammation & intermittent obstruction of biliary ducts
Dwelling in bile ducts induces
Inflammatory reaction
Hyperplasia
Cholangiocarcinoma (glandular cancer of bile ducts)
Possibility of adult metacercaria to consume all of bile duct in liver
Inhibits host from digesting food
Overcrowding of common bile duct
Risk of bile duct and gallbladder exploding within human body

17. Detrimental Effects
Eggs and worms that somehow migrate out of the biliary system may become nuclei of eventual gallstones.
Metacercariae travelling through the body can cause high fevers in the host.
May lead to possible disturbance of normal hepatic functions
Clonorchis Sinensis in rabbits leads to higher levels of potassium and cholesterol, lower calcium levels, lipid metabolism and glycogen synthesis are impaired.

18. Where is it found?
Endemic areas are Asia including Korea, China, Taiwan, and Vietnam.
Occasionally reported in non-endemic areas (including the United States).

19. Epidemiology
19 million are infected in heavily populated regions of China
Southern provinces, Taiwan, Hong Kong, Red River, Korea, Japan
Cases also reported in Europe, United States, Middle East, China, Japan, and Africa.
Usually caused by immigrants from regions in China
Acquired by Hawaiians by eating raw, frozen, or salted fish shipped from China or Japan.

20. New Epidemiological Characteristics
change in diet from mainly grain and vegetable to fish and meats in China
The difference of infection rate between urban and rural areas is reducing.
Endemic area tends to expand gradually.

21. What Can be Done? Health education Environmental modification
Reform of traditional farming and fishing techniques
Mass screening and chemotherapy
Management of domestic animals are needed in developing control strategies to decrease spreading
Controlling the use of "night soil" (fertilizer contaminated with human feces), used to fertilize fish ponds
Avoid eating raw fish and using contaminated water for consumption.

22. Diagnosis
Depends on recovering and identifying the parasite’s eggs in stool sample.
Diagnostic Tests: medical history, physical assessment (palpation of the liver), ELISA blood test
Medical Tests: endoscopy and examination of stool sample, radiological and sonographic assessments, surgery

23. Medications Praziquantel Albendazole Drug of choice for treatment
Increases cell membrane permeability in worms, resulting in paralysis of worm’s musculature
Attachment of phagocytes and death
Cons: bitter taste may cause nausea
Albendazole
Inhibits metabolism in worm’s cells
Immobilization & death of worm follow

24. Bibliography
Eckroad, E. and H. Lee "Clonorchis sinensis" (On-line), Animal Diversity Web. Accessed October 07, 2006 at <
Brusca, R., G. Brusca Invertebrates. Sunderland, Massachusetts: Sunauer Associates, Inc..
Buchsbaum, M., R. Buchsbaum, V. Pearse, J. Pearse Living Invertebrates. Boston, Massachusetts: Blackwell Scientific Publications.
Chappell, L Physiology of Parasites. New York: John Wiley and Sons.

25. Bibliography
Clay, T., M. Rothschild Fleas, Flukes and Cuckoos. New York: The MacMillan Company.
Swellengrebel, N., M. Sterman Animal Parasites in Man. Princeton: D. Van Nostrand Company, Inc..
von Brand, T Endoparasitic Animals. New York: Academic Press Inc., Publishers.