Determination of High Risk Regions of Cutaneous Leishmaniasis in Turkey Using Exploratory Spatial Analysis

Objectives: Geographic Information Systems (GIS) have had a place in public health and epidemiologic investigations. This study aims to explore geographical analysis of distribution of cutaneous leishmaniasis among the provinces of Turkey, and identifies infection cluster provinces as priority areas to implement precautionary measures by health agencies for public health planning.Material and Methods: GIS based spatial analyses were performed to report cutaneous leishmaniasis cases that were recorded by the Turkish Ministry of Health for 1996-2006 periods. Empirical Bayes smoothing was used to remove background noise from the raw disease rates because of the sparsely populated provinces and small number of cases in the provinces. To detect global variations and trends in the incidence rates over the neighboring provinces, spatial rate smoothing based on spatial moving areas technique was performed. Cluster analysis methods were performed whether the cases of cutaneous leishmaniasis showed clustering or located closer by chance.
Results: The spatial distribution of cutaneous leishmaniasis cases was nonrandom and detected as clustered with significant values of (p<0.05). There is a clear trend towards the South East Anatolian region. Regions with high concentration of cutaneous leishmaniasis are located in the South East Anatolian region.
Conclusions: This study shows that cutaneous leishmaniasis is a serious public health concern in the South East region of Turkey, and that region should have a priority to implement precautionary measures. It also shows that spatial analyses and statistics can contribute to understanding epidemiology of diseases, and identifying high rate disease locations.