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

O município de Campo Grande, Estado de Mato Grosso do Sul, Brasil, apresenta ocorrência de casos humanos e caninos de leishmaniose visceral desde 2002 e é classificado como área com transmissão intensa. O estudo foi realizado no período de maio de 2003 a abril de 2005, em parceria com a Fundação Nacional de Saúde e a Secretaria de Saúde do Estado, com o objetivo de conhecer o comportamento e a sazonalidade da espécie Lutzomyia longipalpis. As capturas foram realizadas com armadilhas luminosas, tipo CDC, em doze estações distribuídas na zona urbana. As estações com maior densidade situam-se na parte sul da cidade e a abundância relativa aumentou durante, ou logo após, as precipitações pluviométricas. Nos meses frios e secos a quantidade foi reduzida e a abundância relativa foi maior no peridomicílio. A borrifação com alphacypermetrina, em intervalos de quatro meses, contribuiu para a diminuição do vetor em três das quatro estações borrifadas e, das oito que não sofreram intervenção química, cinco tiveram aumento.

INTRODUCTION: This study sought to describe the profile and geographic distribution of reported cases of visceral leishmaniasis (VL) in the City of Campo Grande, State of Mato Grosso do Sul (MS), Brazil, from 2002 to 2009. METHODS: Human data were collected from the Brazilian National Information System for Notifiable Diseases. Canine cases and entomological data were obtained from the Information Service for Canine Visceral Leishmaniasis Control/Campo Grande, MS. RESULTS: A total of 951 records from 2002 to 2009 were investigated. The number of reported cases of VL in males was significantly higher (p < 0.0001) than that in females. The higher frequency observed among males was associated with age (p < 0.0001), which increased in individuals aged 40 years and older. The overall fatality rate was 7.4%. Entomological surveys conducted in 2006, 2007, and 2009 showed the insect vector Lutzomyia longipalpis to be present in all urban regions of the county. CONCLUSIONS: VL cases in humans and dogs, as well as in vectors, occurs in all urban regions of Campo Grande. Despite not observing tendencies of increase or reduction in the incidence of the disease due to aging, the major incidence in men is higher in those aged 40 years or above.

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The life cycle of vectors and the reservoirs that participate in the chain of infectious diseases have a strong relationship with the environmental dynamics of the ecosystems in which they live. Oscillations in population abundance and seasonality of insects can be explained by factors inherent in each region and time period. Therefore, knowledge of the relationship and influence of environmental factors on the population of Lutzomyia longipalpis is necessary because of the high incidence of visceral leishmaniasis (VL) in Brazil. This study evaluates the influence of abiotic variables on the population density and seasonal behavior of L. longipalpis in an urban endemic area of VL in Brazil. The sand fly captures were performed every two months between November, 2009 and November, 2010 in the peridomicile of 13 randomly selected residences. We captured 1,367 specimens of L. longipalpis, and the ratio of male/female flies was 2.86:1. The comparison of the total male specimens in the two seasons showed a statistical difference in the wet season, but there was no significant difference when considering the total females. With respect to climatic variables, a significant negative association was observed only with wind speed. During periods of high wind speeds, the population density of this vector decreased. The presence of L. longipalpis was found in all months of the study with bimodal behavior and population peaks during the wet season. Journal of Vector Ecology 38 (2): 224-228. 2013.