Superfamily Trichinelloidea Flashcards
What is the name of the super family of Trichuris spp.?
Trichinelloidea
What is the common name of Trichuris spp.?
Whipworm
What is a common morphological feature with the members in this super family?
“Stichosome” esophagus - composed of capillary-like tube surrounded by a single column of cells.
Name the 3 species of interest in this super family and their sites of infection.
- Trichuris - cecum and colon (mammals)
- Capillaria - alimentary, respiratory, hepatic or urinary tracts (mammals and birds)
- Trichinella - small intestine
What are the hosts for Trichuris spp.?
Dogs and Cats
What are the characteristic features of adult Trichuris spp.?
Adults are 4-6 cm long with a thick posterior end and a long filamentous anterior end, hence resembling a whip.
What are the characteristic features of the Trichuris spp. eggs?
Eggs are lemon shaped, yellow or brown in color, containing bipolar plugs. 80 x 35 micrometers
Name the parasitic species in this image.
Trichuris Vulpis
What is this image showing?
Trichuris Vulpis eggs
Can you identify the multiple parasitic species in this image?
Trichuris Vulpis and Spirocerca Lupi
Explain the life cycle of Trichuris Vulpis.
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.
Where is the site of infection for Trichuris Vulpis?
Large intestine, particularly cecum
What are the pathogenesis and lesions of Trichuris Vulpis?
Large numbers cause diphtheritic inflammation of cecal mucosa
What are the clinical signs of Trichuris Vulpis
Heavy infections cause watery bloody diarrhea
How is Trichuris Vulpis diagnosed?
Eggs in feces
What is the treatment and preventative for Trichuris Vulpis?
Use anthelmintics. Remember, eggs can survive for 3-4 years in environment
What Super family does Capillaria spp. belongs to?
Trichinelloidea
What is the common name for Capillaria spp.?
Lungworm
What are the hosts for Capillaria spp.?
Dogs and Cats
Is Capillaria spp. zoonotic?
Yes, but it is rare for humans to get
What are the characteristic features of adult Capillaria spp.?
Adults are thin hair-like nematodes not visible to naked eye. 1-5 cm long
What are the similarities and differences between Trichuris eggs and Capillaria eggs?
Similarity: both have bipolar plugs
Differences: Capillaria eggs are lighter in color and more barelled shaped than Trichuris. 60 x 35 micrometers
Can you distinguish the different parasitic species in this image?
Top egg is Capillaria spp. and bottom egg is Trichuris spp.
What life cycle does Capillaria spp. have, direct or indirect?
Both! Depends on species. Infective stage is L1 in egg
Describe the direct life cycle in Capillaria spp.
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
Describe the indirect life cycle of Capillaria spp.
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.
Where are the sites of infection for Capillaria spp.?
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
What are the pathogenesis and lesions of Capillari spp.?
Relatively non-pathenogenic
What are the clinical signs of Capillaria spp.?
Asymptomatic
How is Capillaria spp. diagnosed?
Eggs will be noted in the feces, urine, or bronchial swab
What are the treatment and prevention for Capillaria spp.?
Several anthelmintics reported to be effective. Control of intermediate hosts is not practical
