Evolvement Of Spatial-temporl Pattern Of Schistosomiasis In Nanchang County

Nanchang County is a heavily schistosomiasis endemic county in Jiangxiprovince along the Poyang Lake, in2009the infection rates of administrative villagesare0.02-9.998%with great uneven spatial distribution. With WHO’s aiddiscontinuation，the input funds has become less，how to make the limited in resourcebring the greatest benefit is a question，a large number of studies showed that there isimportant significance in schistosomiasis control work in detecting schistosomiasisclustering areas when allocating limited resources.Based on the data of schistosomiasis infection rate by unit of administrativevillages during2006-2009period, this paper analyzed the evolution ofspatial-temporal pattern of schistosomiasis infection by means of global Moran’s I、Getis-Ord General G、 local Getis-Ord Gi*and variogram， and explored thecharacteristics and rationale of the epidemic distribution in2009grounded on fieldsurvey data.（1）Combined use of local autocorrelation, spatio-temporal scan statistic methodcoupled with auxiliary field investigation information, the epidemic clustering patternusing spatial association weight matrix at5000m interval tallies with the reality most.（2）Since2006, the global Moran’s I index was becoming increased, theGetis-Ord General G index G(d) persisted at0.02(significance level <0.01),indicating obvious spatial clustering pattern of schistosomiasis infection. The hotspotsdistributed in the northeast and southeast portions of the county, the cold spots andsecondary cold spots in the southwest.（3）The optimal fitted variograms are the same as Gaussian model, Nuggetsdecreased from0.026to0.006, indicating spatial variation introduced by randomnesswas dropping down, impact from structural power was becoming stronger; the spatial auto-relationship is getting stronger, the Ranges shrank by9.04%, implying the effectsof spatial linkage led by structural gradients was being reduced, the infection wasclosing onto the hotspots gradually.（4）Multivariate step-wise regression results reveals: infected water contactingindex of per unit area, and the number of livestock，the Poyang Lake boundary ofadministrative village can explain83.5%of total variation of2009’s infection rate.