Taeniid Cestodes

Question 1

Significance of taeniids

Answer 1

livestock and meat industry

some zoonotic

clinical disease (humans)

Public health impact

Question 2

What is a cysticercosis

Answer 2

Cyst in the IH

Question 3

Random taenia facts

Answer 3

• Branched uterus
• unpaired genitals
• genital pores in irregular sequence on either side

Question 4

Types of larval cysts

Answer 4

Cysticercus-> cysticercosis - Taenia

Coenurus-> coenuriasis - other Taenia

Hydatid-> hydatidosis - Echinococcus spp

Question 5

Taenia solium (pork measles worm) lifecycle and host

Answer 5

Egg -> Oncosphere -> Cysticercus (pig, humans, muscles/CNS) -> adult (humans)

Question 6

Features of Taenia solium

Answer 6

• usually only 1 adult in SI (ie. solium)
• 5-10m long

Question 7

Laval stage of Taenia solium

Affinity

Answer 7

Cysticercus cellulosae

Oncosphere carried in blood stream to brain, muscles and subcutis tissue. Affinity for nervous tissue

Question 8

Taenia saginata IH

and DH

Answer 8

Cattle; musculature

Humans

Question 9

Taenia saginata common name

size

larval stage name and distribution

Answer 9

beef measles worm

5-15m

Cysticercus bovis in muscles.

Question 10

Lifecycles of human Taenia

Answer 10

Question 11

Which Taenia?

Answer 11

Taenia saginata

Question 12

Which Taenia?

Answer 12

Teania solium

Question 13

IH of Taenia ovis

Answer 13

Sheep, goat; musculature

Question 14

DH of Taenia ovis

Answer 14

canid; dog and fox

Question 15

Features of Cysticercus ovis

Answer 15

mostly in heart, diaphragm and masseter muscles

Cysts rapidly degenerate to form granulomas

Question 16

What has caused these lesions?

Answer 16

Taenia hydatigena

Question 17

IH of Taenia hydatigena

Answer 17

Ungulates; liver+omentum

Question 18

DH of Taenia hydatigena

Answer 18

canid

Question 19

Common name of Taenia hydatigena

Answer 19

False hydatid worm

Question 20

Cysticercus tenuicollis (from T. hydatigena) features

Answer 20

attached to omentum in sheep, cattle, pigs.

oncosphers burrow through liver for 1 month -> peritoneal cavity and establishes in omentum

may lead to Black Disease

• liver condemnation

Question 21

Taenia pisiformis IH

Answer 21

Rabbit, hares; liver+omentum

Question 22

DH of T. pisiformis

Answer 22

canid

Question 23

Cysticercus forming Taenia

Answer 23

T. solium

T. saginata

T. ovis

T. hydatigena

T. pisiformis

T. taeniaeformis

Question 24

DH of T. taeniaeformis

Answer 24

Felid

Question 25

IH of T. taeniaeformis

Answer 25

rats, mice; liver

Question 26

Larval stage of T. taeniaeformis

Answer 26

Strobilocercus fasciolaris

Question 27

What is a cysticercus

Answer 27

Fluid filled sac with a protoscolex

Question 28

What is a coenurus?

Answer 28

Many protoscolex on the internal surface of a fluid filled sac

Question 29

What is a hydatid?

Answer 29

A fluid case with more coenuri within it

Question 30

What taenia form coenurus?

Answer 30

T. multiceps T. serialis

Question 31

Lifecycle stages of Taenia multiceps

Answer 31

Egg -\> Oncosphere -\> Coenurus (ungulates; CNS) -\> adult (canid)

Question 32

Disease caused by T. multiceps

Answer 32

Progressive (6-8 months) -\> incoordination, head pressing, blindness

Question 33

Differentials of T. multiceps

Answer 33

Listeriosis, parelaphostrongylosis, scrapie, 'mad cow'

Question 34

What caused this lesion?

Answer 34

T. multiceps

Question 35

Where is T. multiceps found?

Answer 35

New Zealand, UK not in Aus

Question 36

IH host of T. serialis

Answer 36

rabbits, hares; subcutaneous

Question 37

Type of cyst? From what species?

Answer 37

Coenurus T. serialis

Question 38

DH of T. serialis

Answer 38

canid

Question 40

What causes hydatid cysts?

Answer 40

Echinococcus

Question 41

Alveolar echinococcosis is caused by?

Answer 41

Echinococcus multilocularis

Question 42

Cystic (unilocular) echinococcosis is caused by?

Answer 42

Echinococcus granulosus

Question 43

Lifecycle of Echinococcus granulosus + epidemiology

Answer 43

Endemic in Aus Has domestic (pig, sheep, cattle) and sylvatic (kangaroo) cycles

Question 44

Common name of Echinococcus granulosus

Answer 44

Hydatid tapeworm

Question 45

Size og Echinococcus granulosus how many segments? How many strains?

Answer 45

2-5mm 3-5 segments 9 strains

Question 46

Pathology of Echinococcus granulosus in canids

Answer 46

No pathology and no protective immunity

Question 47

Pathogenesis of E. granulosus in IH

Answer 47

Primary hydatidosis - pressure atrophy and collateral circulation Secondary hydatidosis (rupture) - Anaphylactic shock due to a huge amount of antigen formed

Question 48

How to treat hydatidosis?

Answer 48

Surgical removal - have to drain cycsts first Benzimidasols have low efficacy

Question 49

Lifecycle of Echinococcus multilocularis

Answer 49

Alveolar hydatid in rodents/humans Egg -\> oncosphere -\> alveolar hydatid -\> adult

Question 50

Features of the larvae

Answer 50

Invasive and metastatic properties. Therefor surgical excision is almost impossible.

Question 51

Distribution of E. multilocularis

Answer 51

Not in Aus