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The characterization of behavioral patterns allows a better understanding of the transmission dynamics and the design of more effective malaria vector control strategies. This study analyzed the behavioral patterns of the Anopheles species of the Coração district situated in the northeast of the Brazilian Amazon region. The behavioral patterns of the anopheline species were measured based on the 36 collection sites of this district from December 2010 to November 2011. Collections of four hours for three consecutive nights each month and four 12-h collections, comprising two in the rainy season and two in the dry season, were performed. Furthermore, to infer the anthropophily and zoophily indexes, four additional four-hour collections were performed. The samples were also evaluated for parity rate and natural infectivity for Plasmodium spp. A total of 1689 anophelines were captured, comprising of nine species and two subgenera ( Nyssorhynchus – six species, and Anopheles – three species). Anopheles darlingi was the most abundant and widely distributed species in the area, followed by A. braziliensis and A.marajoara . Anopheles darlingi and A. marajoara were the only species present in the four collections of 12-h, but only A. darlingi showed activity throughout night. Anopheles darlingi was the most anthropophilic species (AI = 0.40), but the zoophily index was higher (ZI = 0.60), revealing an eclectic and opportunistic behavior. Of the six most frequent species, A. nuneztovari s.l. was the most zoophilic species (ZI = 1.00). All captured species showed predominance towards biting in outdoor environments. Anopheles darlingi and A. braziliensis showed multimodal biting peaks, whereas A. marajoara revealed a stable pattern, with the biting peak after sunset. Using the PCR technique, no anopheline was found infected with the malaria parasite. Since A. darlingi and A. marajoara are recognized as important vectors in this region, the district of Coração may be considered as a highly potent area for transmission of malaria, therefore, the prevention and surveillance measures should be taken constantly to prevent the same. The role of A. braziliensis as malaria vector needs to be urgently investigated. [ABSTRACT FROM AUTHOR]

Abstract: The aim of this study was to assess the prevalence pattern of mixed-Plasmodium falciparum malaria infections in Brazil by molecular diagnosis and to address its clinically important features. DNA was extracted from 115 thick blood film P. falciparum human blood positive samples using the phenol–chloroform method, followed by a semi-nested PCR protocol with species-specific primers. Seventy-three percent of P. falciparum single infections and 26.95% of mixed infections were found. Amongst mixed infections, the majority was double infection (96.77%). Our results suggest that the prevalence of one species over the other can be important on weakening P. falciparum malaria clinical symptoms. We confirm that P. falciparum co-infections frequently occur in Brazilian malaria endemic areas, with underestimated diagnosis. The results point to the need of improving microscopy or changing for another accurate diagnosis technique to differentiate among human malaria species, as this is essential to choose the best treatment and control measure for malaria. More investigations are necessary in order to clarify the role of mixed-infections in the severity of P. falciparum disease. [Copyright &y& Elsevier]