Use of a Health Information System (HIS) for the Epidemiological Surveillance of Leishmaniasis in Urban Areas

In this paper we propose the use of GIS technologies to realize a Health Information System (HIS) for the surveillance of leishmaniasis in urban areas. As an example, we report our experiences and results carrying out an HIS for the surveillance of leishmaniasis in the city of Messina (Italy). The study area was represented by the city of Messina (38.1-N, 15.5-E) in northern Sicily. Cases were registered on digital spreadsheets and were added to the HIS by the use of the geo-code address function. Leishmaniasis both human and dog cases, were represented as HIS as points as well as or a choroplethic map showing the number of cases per quarter. Frequencies of cases/quarter were normalized for the resident quarter population (human or dog) as well as for the quarter surface. Dog cases density for the study area was calculated by the Kernel function and expressed as cases/km2. To evaluate the number of infected dogs that could act as a source of disease for the people hosted in the more at risk buildings, buffer zones, paste on sand flies feeding range, were drawn around the building polygons and infected dogs within the buffer area were selected and counted. The HIS approach can provide several types of surveillance activities and analysis, such as: a) total number and the exact geographic position of the reported cases of disease in the city; b) calculated density and occurrence of cases at different levels (i.e. quarters or zip codes); c) analysis of the relationship between human and dog cases and between disease occurrence and economic or social indicators; d) calculation of the number of infected dogs that could be a source of disease for humans in the neighbourhood of more sensitive sites such as hospitals, nursery schools, hospices and others; e) identification of high-risk areas for target control actions on both hosts and vectors