Parasitology Flashcards
What is a definitive?
A host where the parasite undergoes sexual reproduction.
What is an intermediate?
A temporary environment for the parasite; Can’t reach sexual maturity but may undergo asexual replication. Necessary for completion of parasite life cycle.
What is an incidental?
Accidentally infected and not needed for completion of parasite life cycle.
What is a resevoir?
Animals that harbor infections that are infective to humans.
Are parasites eukaryotes or prokaryotes?
Eukaryotes
What makes treating protozoa difficult?
They live in multiple stages, all of which must be eliminated to clear disease.
What makes treating helminths difficult?
They do not proliferate in adult stages; Must target attachment or functions important in egg production
What does praziquantel do?
Exposes the helminth to the host immune system; Does not directly kill the pathogen.
What are the three types of parasites?
Helminths, Protozoa, and ectoparasites
What are the three types of parasite pathogenesis?
Toxins, Mechanical damage, Immune mediated (Hypersensitivities)
Describe Cestodes (Tapeworms)
Flat, ribbon-like, prominent suckers, body divided into segments. No digestive tract; nutrients absorbed through wall
Name some cestodes
Taenia, echinococcus, Diphyllobothrium, Hymenolepis
How is Taenia transmitted?
Fecal-oral; Causes cysts (mechanical damage)
Discuss taenia pathophysiology.
Embryonic eggs develop in human intestine and parasites migrate to various tissues to develop cysts; Location of cyst determines severity of pathology.
How is Taenia diagnosed?
Proglottids (segment) in stool; Cysts in tissue
