Wk18D1 Malaria+Babesiosis Flashcards
The 5 species that cause malaria in humans
Plasmodium falciparum P. vivax P. malariae P. ovale P. knowlesi (primarily infects monkeys)
Best treatment choice for:
P. falciparum
P. vivax
Prophylaxis
Coartem/Malarone
Chloroquin+Primaquine
Malarone/Doxycycline
Plasmodium asexual propagation is called ___ and occurs in ____. Sexual propagation is called ___ and occurs in ____.
Schizogony
Human host
Sporogony
Female mosquito (Anopheles)
Life cycle of Plasmodium
Exo-erythrocytic cycle–Sporocytes invade hepatocytes, develop into merozoites. P. ovale and P. vivax have hypnozoite stage.
Intra-erythrocytic cycle–Merozoites release and infect RBCs, become trophozoites which mature to schizonts. These release many merozoites.
Sexual cycle–Gametocytes taken up by mosquito, produce sporogony and new sporozoites in salivary glands
How to get malaria without being in an endemic area (3 ways).
traveler/immigrant->mosquito->you
Blood transfusion
Mother->Fetus transmission (merozoite)
____ is in hot tropical countries with year-round presence of mosquito vector. ______ is more common in temperate because it survives cold season in its ___ form. ____ is endemic in SE Asia.
Plasmodium falciparum
P. vivax (hypnozoites in the liver)
P. knowlesi
But endemic areas overlap!
Most serious Plasmodium infection is ____.
Severe disease occurs in ___
Effects/symptoms?
Serious complications?
P. falciparum
Children <18 months old
Hemolytic anemia, hypoglycemia, TNF-alpha, microvascular obstruction, splenomegaly
Cerebral malaria, shock, ARDS, renal failure
List the 5 genetic polymorphisms in malaria endemic areas that confer resistance
Duffy RBC antigens (DARC) - vivax/knowlesi Glycophorin A - falciparum Ovalocytosis/elliptocytosis G-6P dehydrogenase - falciparum Sickle cell/thallassemia - falciparum
Can you be re-infected with malaria? Is a vaccine in use?
Yes, but subsequent infections have lessened symptoms. No vaccine :(
Symptoms occur during ___ cycle. Fever can be ___ or ___. Symptoms in non-immune persons resemble ___.
intra-erythrocytic.
tertian or quartan (in cases of re-infection)
Flu (FEVER, head/backache, myalgia, ab pain, nausea, vomiting, diarrhea).
P. malariae can cause ___ problems such as __.
chronic nephrotoxic syndrome (Ag/Ab complex deposition)
To diagnose, take ___ if patient has ___.
Thin blood smears with Giemsa/Wright’s stain for ___.
Thick smears are ___ and used for ___.
Rapid tests may miss ___.
___ is good but not widely available.
Travel history; febrile illness of unknown etiology speciation unhemolyzed; ID level of parasitemia Dual infections PCR-based assays
In blood smears, how do they look? falciparum vivax ovale malariae/knowlesi
F: high density, often >1 ring/RBC with 2 chromatin dots. Banana-shaped gametocytes.
V: large RBCs, Schueffner’s dots
O: Oval/fimbriated RBCs, Schueffner’s dots
M/K: “band” form (trophozoite)
Define: Suppressive treatment Clinical cure Radical cure Suppressive cure
Prevent intra-erythrocytic stage, preclude symptoms
Eliminate intra-erythrocytic stage, resolve symptoms
Eliminate pre- (primaquine) AND intra-RBC (chloroquine) in vivax/ovale
Continue suppression beyond pre-RBC lifespan in falciparum
Malaria prophylactic drugs include
Atovaquone and proguanil (mitochondria/FH2 reductase inhib)
Doxycycline (daily; multidrug-resistant falciparum)
Chloroquine (DOC for P v/o/m)
Mefloquine (CNS tox, funky dreams, for chloroquin-resistant malaria)
