Anopheles species associated with malaria transmission in gold-mining areas of northwest Colombia

Abstract Background In Colombia, mining is one of the main economic activities in four ecoepidemiological areas that contribute approximately 80% of malaria cases per year. Mining activity generates changes in the environment and opens new available breeding sites to be colonized by malaria vector mosquitoes in the area, increasing the malaria transmission risk. Objective To identify the presence of Anopheles species and their role in malaria transmission in five malaria-endemic localities with gold mining extraction in El Bagre, Antioquia, Colombia. Methods A cross-sectional study was conducted in five localities of El Bagre, Antioquia. Adult mosquitoes were collected indoors and outdoors. The taxonomic status of Anopheles species was confirmed by COI sequencing. All mosquitoes were tested by ELISA to establish infection with Plasmodium spp., and infections were confirmed using nested PCR. Immature mosquitoes were captured from the larval habitats. The association between the presence of Anopheles species and the physical parameters of larval habitat was estimated through multiple correspondence analysis and principal component analysis. Findings: Eleven Anopheles species were identified. Six specimens were positive for PCR Plasmodium test: An. darling infected with P. falciparum, An. nuneztovari s.s., and An. punctimacula infected with P. vivax. A total of 106 larval habitats were characterized. Using a multiple correspondence analysis, it was possible to associate the presence of An. triannulatus s.l., An. nuneztovari s.s., An. rangeli, An. oswaldoi B., An. albitarsis I, An. strodei, An. pseudopunctipennis and An. darlingi with larval habitats generated by mining activity. Main conclusions: An. darlingi, An. nuneztovari s.s. and An. punctimacula showed anthropophilic behavior. These species were detected infected with P. falciparum and P. vivax vk 210, confirming their role in malaria transmission in mining areas. The presence of immature stages of these species in gold mining excavations confirms these habitats as potential breeding sites for malaria vectors in El Bagre.