Parasitic Infection Flashcards
What causes a parasitic disease?
Consequence of prolonged, repeated, or high burden infection
What do most parasites require to complete their life cycle?
Human AND nonhuman hosts.
What are the two types of parasitic infections?
Protozoa and helminths
What causes disease from protozoa infection?
Disease is consequence of parasite replication to high numbers (small inoculum required to initiate infection)
In what cells do intracellular protozoa grow?
RBC and macrophages
Where do extracellular protozoan grow?
Lumen of GI tract
What are helminths?
Worms
Are helminths capable of completing their life cycle in humans?
Not typically
What type of infections helminths cause?
- Usually chronic infections that are tolerated by the human host.
- Disease is NOT a consequence of parasitic replication. (Number of worms in is highest number of worms possible)
What arthropod is associated with malaria?
Female Anopheles mosquito
What is a reservoir?
Sources of parasites that do not participate DIRECTLY in transmission
What are the three different types of parasite entry?
Oral ingestions (contaminated food/water); Penetration of the skin (doesn’t have to be broken); Arthropod-borne (bug bites)
What determines the spread and multiplication of parasites?
Species, tissue tropisims, and temperatures.
What is the most important of all the protozoan diseases?
Malaria
What type of cells does malaria target?
RBC
What type of RBC does Plasmodium falciparum target?
All ages of RBC
What type of RBC does Plasmodium vivax/Plasmodium ovale target?
reticulocytes and young RBC