Mapas de riesgo para Hantavirus en el Parque Nacional Conguillío, sur de Chile

Abstract

The risk of infection with Hantavirus depends on factors that determine a probability of contagion with the reservoirs: (a) the vegetation structure and the land use as a primary scene, where specific factors such as composition, structure and density of the vegetation describe elements related to the habitat of the reservoirs, (b) The existence of populations of reservoir rodents, (c) Human establishments, such as availability and density of roads, inhabited areas or human presence (e.g., houses, warehouses). These three factors, brought together, provide the necessary facts to establish the risk. It is important to consider that these factors have a dynamics of seasonal change during the year and natural and man-made environmental modifications. In this way, we seek to understand the risk to which humans beings are submitted in the rural space. The spatial models correspond to representations of the reality observed in a certain area and determined to diverse geographical, topographic, biological, climatic factors, etc. The aim of this study was to establish potential sectors of risk to Hantavirus in a national park of the Region IX of Chile using thematic maps of environmental variables in a Geographical Information System to analyze aereal photograhs by means of photo interpretation, transference, digitalization and graphical-alphanumerical database managing. The vector layer was rasterized using a pixel size of 50 m. The map of risk was constructed using an additive model of layers through the Model Builder 1.0 software, an extension of Arc View 3.2. The base of the procedure was the arithmetic overlay process what overlaps the layers adding the numeric terms of each variable using the same ponderation for every layer (e.g., land use, habitat for the reservoir, seropositivity of the reservoir, human cases and instalations). We present a risk map, for this highly visited park, which signal as the most important risk areas, the areas where all of the turistic infrastructure is installed. © 2008 Sociedad de Biología de Chile.