Abstract: The benign characteristics formerly attributed to Plasmodium vivax infections have recently changed owing to the increasing number of reports of severe vivax malaria resulting in a broad spectrum of clinical complications, probably including undernutrition. Causal inference is a complex process, and arriving at a tentative inference of the causal or non-causal nature of an association is a subjective process limited by the existing evidence. Applying classical epidemiology principles, such as the Bradford Hill criteria, may help foster an understanding of causality and lead to appropriate interventions being proposed that may improve quality of life and decrease morbidity in neglected populations. Here, we examined these criteria in the context of the available data suggesting that vivax malaria may substantially contribute to childhood malnutrition. We found the data supported a role for P. vivax in the etiology of undernutrition in endemic areas. Thus, the application of modern causal inference tools, in future studies, may be useful in determining causation.

No período compreendido entre janeiro de 1996 e dezembro de 1998, administramos derivados da artemisinina em 108 crianças com malária por Plasmodium falciparum, para avaliar a resposta clínica e terapêutica. Foram incluídas apenas crianças com clínica de malária moderada ou grave. No Grupo I, incluímos 62 pacientes e administramos artesunate por via endovenosa. Clinicamente, 50,8% tinham malária moderada e 49,2% malária grave; a parasitemia foi baixa em 53,2%, média em 22,6% e alta em 24,2%; no D2 a parasitemia estava negativa em 58,1%. No Grupo II,incluímos 46 pacientes que receberam artemeter (Paluter®) intramuscular. Clinicamente, 67,4% apresentavam malária moderada e 32,6% malária grave; a parasitemia foi baixa em 52,2%, média em 36,2% e alta em 15,2%; em D2, 56,5% apresentaram negativação da parasitemia. Nos dois grupos, a melhora clínica e evolução da parasitemia não mostraram diferença estatística; no D7 havia clareada a parasitemia em todos os pacientes. Para evitar recrudescência usamos mefloquina ou clindamicina.

From January 1996 to December 1998, artemisinin derivatives were prescribed to 108 children infected with Plasmodium falciparum. The therapeutic effect was evaluated. Only children with moderate or severe malaria were included. Group I (intravenous artesunate; n = 62): 50.8% with moderate malaria and 49.2% with severe malaria; 53.2% with mild parasitemia, 22.6% with moderate parasitemia and 24.2% with high parasitemia; Group II (intramuscular artemether [Paluter®]; n = 46): 67.4% with moderate malaria and 32.6% with severe malaria; 52.2% with mild parasitemia, 36.2% with moderate parasitemia and 15.2% with high parasitemia; clinical amelioration and clearance of parasitemia showed no statistical difference between the groups. All patients cleared the parasitemia at the seventh day of follow-up (D7). In order to avoid recrudescence, mefloquine or clindamycin was used.