Tapeworms

Question 1

What are the general characteristics of tapeworms?

Answer 1

Flattened in shape
Lack a body cavity
Hermaphroditic
Digestive tract incomplete

Question 2

How do you classify tapeworms?

Answer 2

Phylum: Platyhelminthes
Class: Cestoidea (Cestoda)

Question 3

Why are the orders of tapeworms?

Answer 3

Cyclophyllidea: true tapeworm
Pseudophyllidea (diphyllobothriidea): false tapeworm

Question 4

What are some genera of Cystos?

Answer 4

Taenia, echinoccocus, dipylidium

Question 5

What are some genera of Pseudos?

Answer 5

Diphyllobothrium and spirometra

Question 6

What are the true tapeworms of dogs and cats?

Answer 6

Dipylidium caninum
Taenia pisiformis
Taenia taeniaeformis
Taenia multiceps

Question 7

Whar are some other species of true tapeworms?

Answer 7

Echinococcus granulosus
Echinococcus multilocularis

Question 8

What are some species of false tapeworms?

Answer 8

Diphyllobothriidea
Spirometra mansonoides
Diphyllobothrium latum

Question 9

What is the definitive host if Dipylidium caninum?

Answer 9

Dog and cat
In the small intestine

Question 10

Why are the intermediate hosts of Dipylidium caninum?

Answer 10

Flea (body cavity)
Ctenocephalides felis (dogs and cats, most common)
Ctenocephalides Canis (less common)
Lice (rare)

Question 11

Larval infective stage of Dipylidium caninum

Answer 11

Cysticercoid

Question 12

Dipylidium caninum lifecycle

Answer 12

Indirect
Prepatent: 2-3 weeks
Double-pored

Question 13

Dipylidium caninum steps in lifecycle

Answer 13

1. Infected dog or cat pass feces with proglottids (with Dipy eggs), they rupture and release eggs into environment
2. Flea larvae ingest the eggs in the environment and eggs develop into cysticercoids
3. Cysticercoids in body cavity of adult fleas
4. Dogs and cats infected by ingesting fleas
5. Cysticercoids develop into adult tapeworms in small intestine

Question 14

Clinical signs of Dipylidium caninum

Answer 14

Perianal irritation
White rice grain-like proglottids in feces
Rough hair coat
Lethargy

Question 15

How do you diagnose Dipylidium caninum?

Answer 15

Direct smear (more effective)
Fecal flotation

Question 16

How do you treat Dipylidium caninum?

Answer 16

Praziquantel
Combination of flea control and heart worm preventative

Question 17

Public health concerns of Dipylidium caninum

Answer 17

Zoonotic
Observed in children following ingestion of flea containing cysticercoid
Found in intestines
Causes mild disease
Treatable

Question 18

What species of Taenia are common in dogs and cats?

Answer 18

Taenia pisiformis (dog)
Taenia taeniaeformis (cat)
Taenia multiceps (dog)

Question 19

How is the scolex of Taenia in North America?

Answer 19

Armed with 2 rows of hooks

Question 20

Eggs of the Taenia species

Answer 20

Thick shell surrounds the ochosphere which contain hooklets (in center)

Question 21

What are the host of Taenia pisiformis?

Answer 21

Definitive: Dogs (small intestine)
Intermediate: rabbits (abdominal cavity)

Question 22

What is the larval infective stage of Taenia pisiformis?

Answer 22

Cysticercus

Question 23

Lifecycle of Taenia pisiformis

Answer 23

Indirect
Requires a rabbit as the intermediate host
Prepatent: 6-8 weeks

Question 24

Taenia pisiformis lifecycle steps

Answer 24

1. Infected dogs pass feces with proglottids with the eggs, eggs rupture then into environment
2. Intermediate host ingest egg and develop into cysticercus
3. Infected dogs eats infected rabbit
4. Cysticercus develop into adult tapeworms

Question 25

What are the clinical signs of Taenia pisiformis and taeniaeformis?

Answer 25

Symptoms depend on worm burden, age and body condition Enteritis Diarrhea Lethargy

Question 26

How do you diagnose Taenia species (all)?

Answer 26

Direct smear Fecal flotation

Question 27

How do you treat Taenia species (all)?

Answer 27

Praziquantel and Fendendazole

Question 28

Public health significance of Taenia species (all)

Answer 28

Zoonotic (low risk of human becoming infected)

Question 29

Host of Taenia taeniaeformis

Answer 29

Definitive: cats (small intestine) Intermediate: rodents (abdominal cavity)

Question 30

Type of larval infective stage of Taenia taeniaeformis ?

Answer 30

Strobilocercus

Question 31

Lifecycle of Taenia taeniaeformis?

Answer 31

Indirect and requires a rodent as an intermediate host Prepatent: 6-8 weeks

Question 32

Taenia taeniaeformis lifecycle steps

Answer 32

1. Infected cats pass feces with proglottids with the eggs, proglottids rupture then into environment 2. Intermediate host ingest egg and develop into strobilocercus 3. Infected cat eats infected rodent 4. Strobilocercus develop into adult tapeworms

Question 33

Hosts of Taenia multiceps

Answer 33

Definitive: dogs (small intestine) Intermediate: sheep, goats and man (brain and SC)

Question 34

Type of larval infective stage of Taenia multiceps

Answer 34

Coenurus

Question 35

Lifecycle of Taenia multiceps

Answer 35

Indirect Prepatent: 6-8 weeks Produces a neurological condition called GID in sheep

Question 36

Taenia multiceps lifecycle steps

Answer 36

1. Infected dogs pass feces with proglottids with the eggs, proglottids rupture then into environment 2. Intermediate host ingest egg and develop into cornurus 3. Infected dog eats infected sheep or goat 4. Coenurus develop into adult tapeworms

Question 37

What are the clinical signs of the infected hosts of Taeniaeformis multiceps?

Answer 37

Blindness Uncoordination Walking in circles Head pressing Death may occur