Human intervention in the Brazilian Amazon region promotes contacts between humans and vectors that may favor the propagation of anopheline mosquitoes and the spread of malaria in the absence of planning and infrastructure to control this disease. Vector ecology studies were carried out to determine the risk areas. These data should help in designing appropriate malaria control measures. Data from 14 different regions are reported. Vectors are able to adapt to different environments, which made it necessary to study each area. The parameters studied were Anopheles breeding sites, species distribution, incidence, feeding preferences, hours of maximum activity of adult mosquitoes, seasonality, resting places, and the presence of Plasmodium. Species complexes were also studied. Anopheles darlingi may be responsible for maintaining malaria in human populations in this region. A reduction in the population density of A. darlingi in a particular geographic area can sometimes cause the disappearance of malaria. This species feeds at night but has a peak of activity at the beginning of the evening and another at dawn. Other species are mainly crepuscular and all anophelines demonstrated pronounced exophilia. The timing of feeding activities was found to vary in areas altered by human intervention and also depended on the time of the year and climatic conditions. The larvae were more abundant in the rivers with a less acidic pH and rural areas showed the highest larval index.

This study relates multiple parameters that are involved in the occurrence and control of malaria in the Amazon. Ebbs and floods, black and white waters, fishponds, and ''repiquete'' (Amazonian waters phenomenon) influence the density of Anopheles darlingi Root, 1926. The adaptive processes, genetic background, and resilience of Anopheles vectors change in response to climate and environmental changes. This study covers the diversity of anophelines, which increases due to anthropic activities. Regarding strategies for vector control, the following measures are important: (1) use mechanical barriers inside houses (screens and impregnated mosquito nets), (2) determine the level of anopheline resistance to insecticides, and (3) determine the effect of the physiological state of females on malaria transmission effectiveness. Bioinsecticides were found to be efficient in the control of immatures, and there was no alteration of the associated fauna. Data on genetic variability and vector populations demonstrated greater polymorphism in intradomicile subpopulations. Furthermore, knowledge on the structural genome and transcriptome of A. darlingi, associated with bio-ecology and evolution, may indicate an adaptive strategy of this species to the Amazon biome. There are anthropic activities and environmental and climatic changes that favor increased vector density, requiring specific control strategies to reduce populations of this species.

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