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Flashcards in Parasite III Deck (14):

4 malaria species that infect humans

plasmodium falciparum
plasmodium malariae
plasmodium vivax
plasmodium ovale


which one of the malaria species are RBCs not enlarged

p. falciparum and p. malariae


which malaria species have hypnozoites in the liver and what does it do?

p. vivax and p. ovale
they are sleeping sporozoites that go into the liver and remain dormant for 20-30 years and then reactivate causing malaria recurrence


cycle in anophele

mosquito ingests blood meal with gametocytes (only stage transmissible to vector) --> in gut of anophele, it takes 5 days to convert gametocyte to sporozoites --> sporozoites migrate to salivary gland of anophele where it bites a human at night and inoculates them with sporozoites --> migrates to liver where it takes 8 days to become hypnozoite --> released as merozoites from liver into RBC to become trophozoite --> becomes erythrocytic schizont in 36 hours --> released as gametocyte


describe plasmodium vivax

developing and thick (signet) ring form; enlarged RBCs


what are the three symptom stage in malaria

cold stage: skin dry, pale and cold, rapid pulse and low volume, lasts 1 hr

hot stage: temp high, pulse rapid, last 2-6 hours

sweating: last 2-4 hrs


specific symptoms for plasmodium falciparum

microcirculatory arrest, cerebral malaria --> retinal hemorrhages, coma, coma with eyes open but unseeing, decerebrate and decorticate rigidity, dysconjugate gaze


why do we get cerebral malaria in plasmodium falciparum

P. falciparum schizonts adhere to endothelial endothelium of brain


population more susceptible to malaria

pregnant women because mosquitoes are really attracted to them


treatment for plasmodium falciparum

-quinine or quinadine (IV quinine): used as a reserve drug and treats all blood stages
-those that are chloroquine resistant you will use combination drug of --> sulfadoxine/pyramethamine/meflaquine


treatment for plasmodium malariae



treament for plasmodium vivax/ovale

chloroquine for the blood stages which it destroys all of
primaquine for the hypnozoites in the liver


prophylactic drug for malaria

meflaquine (lariam), doxycycline, chloroquine (aralen), malarone (atavaquone and proguanil)


how does the heterozygote for sickle cell anemia lead to survival advantage against malaria

infected RBCs sequestered deep in the RES -- exposed to low O2 tension permits K+ loss --> leads to low pH which inhibits parasite growth