ABSTRACT
Objective The characteristics of spatial-temporal distribution on infected snails were analyzed at the village level in Anhui province,2006-2012.Methods Data on the distribution of infected snails from 2006 to 2012 in Anhui province was collected.Spatial database was established by ArcGIS 9.3.Retrospective spatial-temporal cluster analysis was done by SaTScan 9.1.1 at the village level.Results Eight areas with increased risk and distributed along the upstream to downstream of Yangtze and connecting branch rivers,were found having infected snails,from 2006 through 2012,including one area in 2006,five in 2006-2008,one in 2007-2009 and one in 2009-2011,respectively.Proportion on the number of areas with infected snails decreased from 6.2％ in 2006 to 0.5％ in 2012.Conclusion The spatial-temporal distribution of infected snail was not random but there appeared significant clusters.The trend seemed to be declining in Anhui province,between 2006 and 2012.Areas being detected as smails positive were important for the schistosomiasis control program to be carried out in Anhui province.
ABSTRACT
<p><b>OBJECTIVE</b>To evaluate the effect of comprehensive control strategy of schistosomiasis with emphasis on infection source control in Anhui province.</p><p><b>METHODS</b>Forty endemic villages in Guichi district, Chizhou city, Anhui province were selected as national pilot villages in the years from 2006 to 2008, and another 10 provincial pilot villages were respectively selected from 10 highly endemic villages in 7 cities in 2007. The comprehensive infection source control measures, including "replace cattle with machines", "raise livestock in pens", "improve the sanitary toilets", "supply safe water " and so on were carried out among the above pilot villages. At the end of 2008, 13 national pilot villages and 6 provincial pilot villages were selected to investigate the popularity of schistosomiasis, and the effect of the comprehensive control strategy in those villages were compared.</p><p><b>RESULTS</b>After implementing the comprehensive control strategy, the infectious rate of schistosomiasis in national pilot villages decreased from 4.57% (487/10 659) to 1.76% (147/8370), with the reduction rate at 61.49%, whose difference showed statistical significance (χ(2) = 115.16, P < 0.01); and the density of infected snails decreased from 0.0067/0.1 m(2) to 0.0008/0.1 m(2), the infectious rate of snails decreased from 0.28% to 0.04%, whose reduction rates were 88.06% and 85.71% respectively. While as to the provincial pilot villages, the infectious rate of schistosomiasis decreased from 1.27% (54/4254) to 0.21% (14/6592), with the reduction rate at 83.46%, whose difference showed statistical significance (χ(2) = 94.57, P < 0.01); and the density of infected snails decreased from 0.0025/0.1 m(2) to 0.0003/0.1 m(2), the infection rate of snails decreased from 0.13% to 0.05%, whose reduction rates were 88.00% and 61.54% respectively.</p><p><b>CONCLUSION</b>The comprehensive control strategy with emphasis on infection source control implemented in marshland and lake regions can effectively control the transmission of schistosomiasis.</p>