Flashcards in Malaria Deck (18):
What's the limiting factor for the transmission of malaria?
Transmitted by mosquitoes, no person-to-person transmission + there is an incubation/replication period within mosquito. 2 weeks before it can infect humans
What are the two major malaria species causing human disease?
T/F P. vivax poses huge health burden in Africa
False, sickle cell provides immunity against vivax in particular
Which Plasmodium species causes zoonotic infection
What are the two forms of malaria parasite?
What's the pathophysiology of malaria infection?
mosquito injects parasite. Sporozoites parasite invades liver within 1-2 hours, followed by 7-10 days incubation. Merozoites eventually burst out of hepatocytes and enter blood stage infection
How does malaria cause metabolic acidosis
malaria induced haemolysis, leading to reduced tissue perfusion, and metabolic acidosis, which will then cause respiratory distress
What is the treatment for severe malaria?
IV infusion of anti-malarial artemisinin + supportive treatment
What are the consequences of unrestricted replication of malaria in blood?
accumulation of parasites in vital organs
T/F P. vivax can be completely cleared from blood
P. falciparum is more challenging to treat
T/F We cannot generate immunity against malaria
False, but only after many episodes
What are the three main types of malaria immunity?
Immunity against severe malaria, any malaria, or malaria in pregnancy
What are some reasons for the slow development of immunity
host inadequate response + poor memory of immunity
Which cells are the targets of acquired malarial immunity?
sporozoites + merozoites
infected hepatocytes + RBC
T/F immunity against infected hepatocytes is relatively effective
False, because of the low parasite load and short duration of infection, the immunity is not very good
Is RBC a good target of malarial immunity?
Yes, but in the right balance. CD4 immunity is not viable because RBCs lack MHC molecules, so immunity relies on the right amount of cytokines
Enough = protection
Too much = severe disease
How do we generate antibodies to merozoites?
infected RBCs will display proteins that activate complement system/opsonisation and enhances phagocytosis
However, passive transfer of antibodies needs to occur for this protection