OBJECTIVETo compare the application valuable of flexible spatial scan statistics and kulldorff scanning window in the cluster detection and early warning of hepatitis A.

METHODSThe case numbers and incidence data of hepatitis A in 2012 for all the counties (cities, districts)in Yunnan province were collected from China Information System for Disease Control and Prevention and the total number was 1 335. By extracting the time length by month, the flexible spatial scan statistics was tested by retrospective analyses of hepatitis A data in Yunnan in 2012 and compared the results with the Kulldorff circular scan statistic analyses.

RESULTSThe results of flexible scanning window showed that there were fifteen hepatitis A spatial clusters in Yunnan province in 2012 and in July, these areas including Gejiu county, Mengzi county and Wenshan county had the strongest clusters (the log likelihood ratio (LLR) = 52.66, P = 0.001). The results of Kulldorff scanning window showed that there were twenty hepatitis A spatial clusters and these areas including Gejiu county, Hekou county, Maguan county, Mengzi county, Pingbian county, Wenshan county had the strongest clusters (LLR = 47.82, P = 0.001). The results of the flexible scanning window were the same as the actual monitoring results. But the results of Kulldorff scanning window showed that in May and June some areas without incidence had the clusters.

CONCLUSIONFlexible scanning window can detect the monthly clusters of the Hepatitis A. Flexible scanning window had a higher accuracy than Kulldorff irregular circular scanning window. Flexible spatial scan statistics had the value in the use of spatial aggregation detecting on hepatitis A.