Evolução temporal da resistência in vitro do Plasmodium falciparum às drogas antimaláricas em duas áreas da amazônia brasileira com distintas características sócio-econômicas e geográficas

Abstract

We evaluated the temporal progression of in vitro P. falciparum resistance to chloroquine, amodiaquine, quinine and mefloquine in two areas with distinct socioeconomical and geographical characteristics: Lourenço, in Amapá state and Paragominas, in Pará state. The former region is essentially an "open" gold mining camp, whereas the latter is one currently undergoing a colonization settlement process, in addition to expanding economical activities which mainly include cattle raising and wood exploitation. Our results show high resistance rates to chloroquine in the two study areas: 79.8% and 68.4% in Lourenço and Paragominas, respectively. Variations in the response of P. falciparum to both amodiaquine and quinine were recorded throughout the study period. On the other hand, no mefloquine P. falciparum resistant strains could be identified, despite the tact we had noted a decrease in sensitivity to this antimalarial drug throughout the study period.

In Vivo Efficacy of Mefloquine for the Treatment of Falciparum Malaria in Brazil

“…The credibility of such programs depends on a high mefloquine efficacy. Although there seem to be no published reports of widespread mefloquine resistance in Brazil [5][6][7], periodic clinical trials should be conducted to monitor its efficacy, especially because of the possibility of mefloquine cross-resistance with quinine [8]. When we initiated this study, there had been no reported clinical studies of mefloquine in Brazil for over a decade, during which time mefloquine resistance rose dramatically in Southeast Asia [9].…”

Chemotherapy of malaria and resistance to antimalarial drugs in Guayana area, Venezuela.

“…As is known, self-medication and subcurative doses favor the selection of resistant parasite populations, which are frequent in areas of high malarial transmission. [8][9][10][11][12][13][14] Another factor that may influence the development of high resistance of P. falciparum to chloroquine (although no studies have been performed) could be the uncontrolled population migration movements within and into and out of the municipality of Domingo Sifontes and surrounding areas, as proposed above. Similar results have been showed by many authors.…”