Superfamily Trichinelloidea

Question 1

What is the name of the super family of Trichuris spp.?

Answer 1

Trichinelloidea

Question 2

What is the common name of Trichuris spp.?

Answer 2

Whipworm

Question 3

What is a common morphological feature with the members in this super family?

Answer 3

“Stichosome” esophagus - composed of capillary-like tube surrounded by a single column of cells.

Question 4

Name the 3 species of interest in this super family and their sites of infection.

Answer 4

1. Trichuris - cecum and colon (mammals)
2. Capillaria - alimentary, respiratory, hepatic or urinary tracts (mammals and birds)
3. Trichinella - small intestine

Question 5

What are the hosts for Trichuris spp.?

Answer 5

Dogs and Cats

Question 6

What are the characteristic features of adult Trichuris spp.?

Answer 6

Adults are 4-6 cm long with a thick posterior end and a long filamentous anterior end, hence resembling a whip.

Question 7

What are the characteristic features of the Trichuris spp. eggs?

Answer 7

Eggs are lemon shaped, yellow or brown in color, containing bipolar plugs. 80 x 35 micrometers

Question 8

Name the parasitic species in this image.

Answer 8

Trichuris Vulpis

Question 9

What is this image showing?

Answer 9

Trichuris Vulpis eggs

Question 10

Can you identify the multiple parasitic species in this image?

Answer 10

Trichuris Vulpis and Spirocerca Lupi

Question 11

Explain the life cycle of Trichuris Vulpis.

Answer 11

Infective stage is L1 in egg -> after ingestion of infective stage, plugs are digested and the released L1 penetrate the glands of the cecal mucosa -> develop to adults which then emerge to lie on mucosal surface with anterior ends embedded -> adults copulate, female lay eggs and pass into feces. PPP is 6-12 weeks.

Question 12

Where is the site of infection for Trichuris Vulpis?

Answer 12

Large intestine, particularly cecum

Question 13

What are the pathogenesis and lesions of Trichuris Vulpis?

Answer 13

Large numbers cause diphtheritic inflammation of cecal mucosa

Question 14

What are the clinical signs of Trichuris Vulpis

Answer 14

Heavy infections cause watery bloody diarrhea

Question 15

How is Trichuris Vulpis diagnosed?

Answer 15

Eggs in feces

Question 16

What is the treatment and preventative for Trichuris Vulpis?

Answer 16

Use anthelmintics. Remember, eggs can survive for 3-4 years in environment

Question 17

What Super family does Capillaria spp. belongs to?

Answer 17

Trichinelloidea

Question 18

What is the common name for Capillaria spp.?

Answer 18

Lungworm

Question 19

What are the hosts for Capillaria spp.?

Answer 19

Dogs and Cats

Question 20

Is Capillaria spp. zoonotic?

Answer 20

Yes, but it is rare for humans to get

Question 21

What are the characteristic features of adult Capillaria spp.?

Answer 21

Adults are thin hair-like nematodes not visible to naked eye. 1-5 cm long

Question 22

What are the similarities and differences between Trichuris eggs and Capillaria eggs?

Answer 22

Similarity: both have bipolar plugs

Differences: Capillaria eggs are lighter in color and more barelled shaped than Trichuris. 60 x 35 micrometers

Question 23

Can you distinguish the different parasitic species in this image?

Answer 23

Top egg is Capillaria spp. and bottom egg is Trichuris spp.

Question 24

What life cycle does Capillaria spp. have, direct or indirect?

Answer 24

Both! Depends on species. Infective stage is L1 in egg

Question 25

Describe the direct life cycle in Capillaria spp.

Answer 25

Adult worms in lungs produce eggs -\> eggs coughed up are swallowed -\> eggs in intestine are then passed in feces -\> eggs embryonate in the feces -\> embryonated eggs ingested by dog or cat. PPP 6 weeks

Question 26

Describe the indirect life cycle of Capillaria spp.

Answer 26

Adult worms in urinary bladder -\> unembryonated eggs passed in urine -\> eggs embryonate in environment -\> Embryonated eggs ingested by final host (dog) or by intermediate host (earthworm) -\> earthworm ingested by dog. PPP is 2 months.

Question 27

Where are the sites of infection for Capillaria spp.?

Answer 27

Direct - in airways of dogs and cats. PPP 6 weeks Direct - in intestinal tract of cats Indirect/Direct - in bladder of dogs, rarely cats. PPP 2 months

Question 28

What are the pathogenesis and lesions of Capillari spp.?

Answer 28

Relatively non-pathenogenic

Question 29

What are the clinical signs of Capillaria spp.?

Answer 29

Asymptomatic

Question 30

How is Capillaria spp. diagnosed?

Answer 30

Eggs will be noted in the feces, urine, or bronchial swab

Question 31

What are the treatment and prevention for Capillaria spp.?

Answer 31

Several anthelmintics reported to be effective. Control of intermediate hosts is not practical