BACKGROUND: In Brazil, 99% of malaria cases are concentrated in the Amazon, and malaria's spatial distribution is commonly associated with socio-environmental conditions on a fine landscape scale. In this study, the spatial patterns of malaria and its determinants in a rural settlement of the Brazilian agricultural reform programme called "Vale do Amanhecer" in the northern Mato Grosso state were analysed. METHODS: In a fine-scaled, exploratory ecological study, geocoded notification forms corresponding to malaria cases from 2005 were compared with spectral indices, such as the Normalized Difference Vegetation Index (NDVI) and the third component of the Tasseled Cap Transformation (TC_3) and thematic layers, derived from the visual interpretation of multispectral TM-Landsat 5 imagery and the application of GIS distance operators. RESULTS: Of a total of 336 malaria cases, 102 (30.36%) were caused by Plasmodium falciparum and 174 (51.79%) by Plasmodium vivax. Of all the cases, 37.6% (133 cases) were from residents of a unique road. In total, 276 cases were reported for the southern part of the settlement, where the population density is higher, with notification rates higher than 10 cases per household. The local landscape mostly consists of open areas (38.79 km²). Training forest occupied 27.34 km² and midsize vegetation 7.01 km². Most domiciles with more than five notified malaria cases were located near areas with high NDVI values. Most domiciles (41.78%) and malaria cases (44.94%) were concentrated in areas with intermediate values of the TC_3, a spectral index representing surface and vegetation humidity. CONCLUSIONS: Environmental factors and their alteration are associated with the occurrence and spatial distribution of malaria cases in rural settlements.
BACKGROUND: In Brazil, 99% of malaria cases are concentrated in the Amazon, and malaria's spatial distribution is commonly associated with socio-environmental conditions on a fine landscape scale. In this study, the spatial patterns of malaria and its determinants in a rural settlement of the Brazilian agricultural reform programme called "Vale do Amanhecer" in the northern Mato Grosso state were analysed. METHODS: In a fine-scaled, exploratory ecological study, geocoded notification forms corresponding to malaria cases from 2005 were compared with spectral indices, such as the Normalized Difference Vegetation Index (NDVI) and the third component of the Tasseled Cap Transformation (TC_3) and thematic layers, derived from the visual interpretation of multispectral TM-Landsat 5 imagery and the application of GIS distance operators. RESULTS: Of a total of 336 malaria cases, 102 (30.36%) were caused by Plasmodium falciparum and 174 (51.79%) by Plasmodium vivax. Of all the cases, 37.6% (133 cases) were from residents of a unique road. In total, 276 cases were reported for the southern part of the settlement, where the population density is higher, with notification rates higher than 10 cases per household. The local landscape mostly consists of open areas (38.79 km²). Training forest occupied 27.34 km² and midsize vegetation 7.01 km². Most domiciles with more than five notified malaria cases were located near areas with high NDVI values. Most domiciles (41.78%) and malaria cases (44.94%) were concentrated in areas with intermediate values of the TC_3, a spectral index representing surface and vegetation humidity. CONCLUSIONS: Environmental factors and their alteration are associated with the occurrence and spatial distribution of malaria cases in rural settlements.
Authors: Virginia Ragoni de Moraes Correia; Antônio Miguel Vieira Monteiro; Marilia Sá Carvalho; Guilherme Loureiro Werneck Journal: Cad Saude Publica Date: 2007-05 Impact factor: 1.632
Authors: Maristela G Cunha; Eliane S Silva; Nuno Sepúlveda; Sheyla P T Costa; Tiago C Saboia; João F Guerreiro; Marinete M Póvoa; Patrick H Corran; Eleanor Riley; Chris J Drakeley Journal: PLoS One Date: 2014-11-24 Impact factor: 3.240
Authors: Aurélia Stefani; Isabelle Dusfour; Ana Paula S A Corrêa; Manoel C B Cruz; Nadine Dessay; Allan K R Galardo; Clícia D Galardo; Romain Girod; Margarete S M Gomes; Helen Gurgel; Ana Cristina F Lima; Eduardo S Moreno; Lise Musset; Mathieu Nacher; Alana C S Soares; Bernard Carme; Emmanuel Roux Journal: Malar J Date: 2013-06-08 Impact factor: 2.979
Authors: Keillen M Martins-Campos; Waléria D Pinheiro; Sheila Vítor-Silva; André M Siqueira; Gisely C Melo; Iria C Rodrigues; Nelson F Fé; Maria das Graças V Barbosa; Wanderli P Tadei; Caterina Guinovart; Quique Bassat; Pedro L Alonso; Marcus V G Lacerda; Wuelton M Monteiro Journal: Malar J Date: 2012-10-23 Impact factor: 2.979