ABSTRACT
Geographic information systems (GIS) methods are multidisciplinary, involving knowledge of physical geography, cartography, remote sensing, global positioning systems (GPS), surveillance. GIS and related geospatial tools are effective in population studies, risk mapping, predictive modelling and the analysis of both social and environmental factors related to infectious diseases. GIS methods used in the study of vector-borne diseases are aimed at identifying environmental factors responsible for pathogen transmission and survival. An important early consideration in working with geographic data is determining the appropriate map scale. Searching for mosquitoes in natural resting sites is a time-consuming and frequently unrewarding occupation. It also requires experience and local knowledge, and negative results are often of little significance. Tests to confirm the presence of normal levels of susceptibility to the insecticide in local populations of vectors are carried out in the course of the pre-intervention period. The geographical location of selected houses should be determined whenever possible using GPS units.
