Parasites Flashcards
May be exposed to a zoonotic organism by:
Inhalation Contact with broken skin Ingestion Contact with eyes and mucous membranes Accidental inoculation with a needle
Parasite
lives in or on another organism and benefits by deriving nutrients at the organism’s expense
Host
an animal or plant on or in which a parasite or commensal organism lives
Primary/ definitive host
A host in which the parasite reaches maturity and reproduces sexually
Secondary host/intermediate host
A host that harbors the parasite only a short transition period
Where some developmental stages are completed
Mosquitos with heartworm
Ectoparasite
A parasite that lives on the exterior of its host
Fleas, lice, ticks, mites
Endoparasite
A parasite that lives within the body of its host
Nematodes, roundworms, heartworms
Obligatory Parasite
Only survives with a host
Periodic Parasite
A parasite that visits the host for short periods
Mosquito
Incidental Parasite
Invades a host that it normally does not
Heartworms and humans
Facultative Parasite
Free-living organisms that can become parasitic if given the opportunity
Maggots
Aberrant Parasite
A parasite that migrates from its usual site of infection
Ocular larva migrans
Pseudoparasite
Creatures or objects that are mistaken for parasites
Grain mites
Paratenic host
A special intermediate host in which a parasite does not undergo any development
Remains arrested in the hosts’ tissue
Toxoplasma gondii
Reservoir host
Can harbor a pathogen indefinitely with no ill effects
May be reinfected several times
