Parasitology 1 Flashcards
Malaria parasite
Plasmodium spec.
Malaria vector
mosquito
Plasmodium falciparum malaria is particularly dangerous and deadly bc of
High parasitemia of all (young and adult) RBC stages and severe cerebral malaria (also-have banana-shaped gametocytes)
P. falciparum cytoadherence results in
adhesion of infected RBCs to placenta (maternal malaria)
Genetic host factors that may partially protect against malaria:
Sickle cell trait (sickle cell hemoglobin, HbS)(esp good against P. falciparum) – Africa; Thalassemia (hemoglobin mutations) – Mediterranean, South East Asia; Glucose-6-phosphate dehydrogenase (G6PDH) deficiency – Mediterranean and Middle East
Plasmodium vivax cause______ & who it infects
most sporadic outbreaks of malaria in southern California and Florida; infects only young RBCs (lower parasitemia)
Sleeping Sickness parasite and transmission?
Trypanosoma brucei
Transmission: Tsetse fly (Restricted to sub-Saharan Africa)
Trypanosoma brucei tricks the immune system by
shedding its outer layer in the blood every few weeks
-requires more blood than regular cells
Tsetse flies
require eyesight; active during day
Chagas’ Disease parasite, transmission, reservoir
Trypanosoma cruzi
Transmission: Triatomine bug (kissing bug)
Spanish: “chinche picuda”
res: wild animals
Trypanosoma cruzi life cycle: human stage
gets into bloodstream, no antigenic variation, causes disease in heart (myocarditis)
Leishmaniasis (Oriental Sore, Kala-Azar) parasite & transmission
Leishmania spp.
Transmission: Sandfly (Phlebotome)
Where does Leishmaniasis occur?
Worldwide
What cells do Leishmania target?
macrophages, dendritic cells
Cutaneous Leishmaniasis (Oriental Sore)
heals in center and spreads on periphery (rim contains macrophages)–T cell mediated (Th1 cells/INF gamma)
usually self-limiting
Toxoplasmosis parasite and transmission
Parasite: Toxoplasma gondii
Transmission: fecal-oral (oocysts in cat litter)
oral (consumption of undercooked meat)
Toxoplasmosis nonhuman hosts
felines are definitive host, produce infective oocysts (banana shaped)
any warm-blooded mammal or bird can serve as intermediate host (infects any nucleated mammalian or bird cell and any tissue)
Clinical Manifestation of Toxoplasmosis
Cerebral toxoplasmosis in immunocompromised patients(AIDS), Congenital toxoplasmosis (Trachyzoites transmitted through placenta)
