Dynamics of Plasmodium falciparum parasitemia regarding combined treatment regimens for acute uncomplicated malaria, Antioquia, Colombia

Abstract

Selecting suitable anti-malarial treatment represents one of the best tools for reducing morbidity and mortality caused by this disease. Sexual and asexual parasite dynamics were thus evaluated in patients involved in antimalarial drug efficacy studies by using combined treatment with and without artemisinin derivatives for treating uncomplicated acute Plasmodium falciparum malaria in Antioquia, Colombia. All treatment doses were supervised and administered according to patients' weight; sexual and asexual parasitemia were evaluated during 28- or 42-days follow-up in 468 patients. Artemisinin-based combination therapy showed greater parasiticidal ability, showing a mean asexual parasitemia survival rate of one day and mean gametocyte survival rate of 1-2 days. Sexual and asexual parasitemias were eliminated more quickly and effectively in the group receiving artemisinin-based combination therapy. Adding 45 mg of primaquine to treatment with artesunate and mefloquine reduced gametocyte and asexual parasite survival by one day.

Figure 1.

Parasitemia dynamics according to treatment regimen, Colombia. A, Percentage of patients having gametocytes per follow-up day. B, Percentage of patients having ring forms per follow-up day. C, Mean gametocytes per follow-up day. D, Mean ring forms per follow-up day. E, Analysis of gametocyte survival per follow-up day. F, Analysis of ring form survival per follow-up day.