Abstract:

Objective To understand the prevalence situation and spatial autocorrelation features of advanced schistosomiasis in Chizhou． Methods The data of advanced schistosomiasis in Chizhou were obtained from the National Surveillance System of Parasite Diseases in 2013. The geographic database of advanced schistosomiasis at the township level and the case database were set up. Statistical analyses were performed to describe the epidemiological features (distribution by age, gender, occupation, and type) of advanced schistosomiasis. The global clustering method( Moran's I) and local clustering methods including local Moran's I and Getis-Ord Gi indices were applied to analyze the spatial distribution of advanced schistosomiasis on Arcgis 10.2. Results A total of 1 855 cases (51.3% were male, 47.7% were female) were reported in Chizhou in 2013. The age ranged between l2 and 93 years old, and 76.0% were over 55 years old. 86.6% of the cases were farmers, 48.4% were illiteracy and 35.6% received primary education. 83.9% of the cases were ascitic type, and 61.0% were first diagnosed as advanced schistosomiasis in 2000- 2009. The global Moran's I of prevalence rate of advanced schistosomiasis was 0.2156 (P<0.05) and there was spatial auto- correlation as a whole．The local Moran's I index and Getis-Ord Gi statistics both found 5 townships, where were located in Dongzhi county, showed High- High positive spatial association with statistical significance (P<0.05). Conclusions The majority of patients with advance schistosomiasis were middle-aged and elderly farmers and most of the patients were ascitic type in Chizhou．A positive spatial correlation of advanced schistosomiasis was found, and 5 clustering townships were identified in Dongzhi County. The findings provided clues useful for disease surveillance and control in Chizhou.

Key words: Advanced schistosomiasis, Geographic information system(GIS), Spatial autocorrelation
analysis