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BackgroundEnvironmental changes caused by urbanization can cause alterations in the ecology and behavior of sandflies and in the epidemiology of leishmaniasis. Geotechnological tools allow the analysis and recognition of spatiotemporal patterns by monitoring and mapping risk areas of this vector-borne disease. This study aims to describe the sandfly fauna in the municipality of Corumbá and to compare it with the data described in a three-year period from 1984 to 1986 by Galati. A further aim was to analyze the influence of environmental changes on the composition of the fauna.MethodsCaptures were conducted weekly from April 2012 to March 2013, in intra and peridomicile areas with automatic light traps, from 6:00 pm to 6:00 am. The following indices were calculated for both periods analyzed: Standardized Index of Species Abundance (SISA), Shannon’s diversity index (H) and Pielou’s index (J). The Normalized Difference Vegetation Index (NDVI) was extracted from a remote sensing LANDSAT-5 image.ResultsIn total, 7,370 specimens (6,169 males and 1,201 females) were collected, distributed among 12 species. Lutzomyia cruzi was the most frequent species (93,79%) and the first in the ranking of standardized species abundance index in both studies. The dominance of the species Lu. cruzi in the neighborhoods of Maria Leite and Centro was demonstrated by the low equitability index. The neighborhood of Cristo Redentor had the greatest diversity of sandflies in the present study and the second greatest in the study performed by Galati et al. (Rev Saúde Pública 31:378–390, 1997). Analyzing the satellite images and the NDVI from 1984 and 2010, the largest amount of dense vegetation was found in the neighborhood of Cristo Redentor.ConclusionsIt was, therefore, possible to show how changes caused due to urbanization have affected the density and distribution of Lu. cruzi and other species over time. Moreover, the data suggest that different populations of sandflies adapt in different ways according to environmental conditions and the adaptation does not necessarily depends on the presence of high vegetation cover.

The relationships between environmental exposure to risk agents and health conditions have been studied with the aid of remote sensing imagery, a tool particularly useful in the study of vegetation cover. This study aims to evaluate the influence of environmental variables on the spatial distribution of the abundance of Lutzomyia longipalpis and the reported canine and human visceral leishmaniasis (VL) cases at an urban area of Campo Grande, state of Mato Grosso do Sul. The sandfly captures were performed in 13 residences that were selected by raffle considering four residences or collection station for buffer. These buffers were generated from the central house with about 50, 100 and 200 m from it in an endemic area of VL. The abundance of sandflies and human and canine cases were georreferenced using the GIS software PCI Geomatica. The normalized difference vegetation index (NDVI) and percentage of land covered by vegetation were the environmental variables extracted from a remote sensing IKONOS-2 image. The average NDVI was considered as the complexity of habitat and the standard deviation as the heterogeneity of habitat. One thousand three hundred sixty-seven specimens were collected during the catch. We found a significant positive linear correlation between the abundance of sandflies and the percentage of vegetation cover and average NDVI. However, there was no significant association between habitat heterogeneity and the abundance of these flies

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BackgroundMato Grosso do Sul has been undergoing a process of urbanization which results in loss of native vegetation. This withdrawal makes vectors of man and domestic animals closer, causing changes in the epidemiology of diseases such as American Visceral Leishmaniasis. The aim of the study was to evaluate the phlebotomine fauna and environmental issues related to the transmission of AVL in Ponta Porã, Mato Grosso do Sul, between 2009 and 2010.MethodsVegetation of the urban area was evaluated by Normalized Difference Vegetation Index (NDVI), Normalized Difference Water Index (NDWI) and Soil Adjusted Vegetation Index (SAVI).ResultsThe results showed that the phlebotomine fauna of the city consists of five species, especially Lutzomyia longipalpis (Lutz and Neiva, 1912), the vector of Leishmania (Leishmania) infantum. Predominance of males was observed. The insects were captured in greater quantity in the intradomicile. Lu. longipalpis was the most frequent and abundant species, present throughout the year, with a peak population after the rainy season. Vectors can be found in high amounts in forest and disturbed environments.ConclusionsThe finding of Lu. longipalpis in regions with little vegetation and humidity suggests that the species is adapted to different sorts of environmental conditions, demonstrating its close association with man and the environment it inhabits. The tourist feature of Ponta Porã reinforces its epidemiological importance as a vulnerable city. The geographical location, bordering Paraguay through dry border, makes possible the existence of a corridor of vectors and infected dogs between the two countries.