PATTERN OF LEPTOSPIROSIS INCIDENCE IN THAILAND: A SPATIOTEMPORAL ANALYSIS
Keywords:
Leptospirosis, spatiotemporal cluster, geoinformatics, scan statisticsAbstract
Human leptospirosis is endemic in many provinces of Thailand, especially in its northeast region.At present, little is known about the spatial and temporal patterns of the disease. The current research applied geoinformatics technology and spatial statistics to analyze the leptospirosis incidence data in Thailand during 2003-2009. Exploratory spatial data analysis was done to demonstrate the geographical distribution of the disease. Kulldorff’s scan statistic was used to detect significant spatial clusters, temporal clusters and spatiotemporal clusters of leptospirosis in Thailand’sprovinces. The results revealed that leptospirosis occurred more in the northeast region than in the others. Seven significant spatial clusters and 11 spatiotemporal clusters were detected during the study period. The most likely spatial cluster and the most likely spatiotemporal cluster were located in the northeast region. There was a significant temporal cluster identified during the high peak of leptospirosis in 2009. This study suggests that the northeast region of Thailand is an important area of leptospirosis transmission which requires closer surveillance.
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