Spirometra spp. (2)

Question 1

What is the common name?

Answer 1

Zipperworm

Question 2

What are the final hosts?

Answer 2

Dogs

Cats

Wild canids

Bobcats

Lynxes

Raccoons

Question 3

What are the intermediate hosts?

Answer 3

1st intermediate hosts: Copepod crustacean

2nd intermediate hosts:

 - Frogs
 - Snakes
 - Reptiles
 - NOT Fish

Question 4

Describe adults

Answer 4

Up to 2 m long

Scolex with bothria

Reproductive organs at centers of segments where eggs are discharged

Question 5

Describe eggs

Answer 5

Operculate

60 micro m

Question 6

Explain life cycle

Answer 6

Eggs develop in water to a coracidium

Coracidium ingested by first IH, a copepod crustacean and procercoid develops

Ingested by second IH (water snake, etc.) and procercoids migrate to muscles or viscera to form plerocercoid

Final host ingests infected second
IH and adult tapeworms develop

Question 7

What is the site of infection for adults?

Answer 7

Small intestine

Question 8

What are the sites of infection in larvae?

Answer 8

In 2 IH

Question 9

Describe the Pathogenesis

Answer 9

Not an issue in FH

Humans infected by consuming Copepods with procercoids in contaminated water or 2nd IH with plerocercoid

Rare: Plerocercoid can be transferred from IH to humans via poultice

Plerocercoid and procercoids migrate around the subcutaneous connective tissue in humans - causes sparganosis

Question 10

How do you diagnose?

Answer 10

Eggs in feces confused with Fasciola hepatica but are half the size

Question 11

How do you treat and prevent?

Answer 11

Treat the tapeworm in final host with cestocide

Where infection common, avoid feeding products derived from intermediate host to domestic animals unless thoroughly cooked

Question 12

What is important about Spirometra spp.?

Answer 12

It is ZOONOTIC