Spatial scan analysis on tuberculosis notifications in Zhejiang province, 2005-2014 / 中华传染病杂志

Objective To analyze the epidemic characteristics of tuberculosis (TB) cases in Zhejiang province from 2005 to 2014, and to identify the cluster spots.Methods TB notification data in Zhejiang province from 2005 to 2014 were analyzed at county and district level by using spatial scan statistic analysis method, which was showed on the digital map.Results In zhejiang province from 2005 to 2014, a total of 377 707 cases of patients with tuberculosis were reported.The average annual registration rates of the entire province was 72.61/100 000 (range: 28.85/100 000-182.90/100 000).Spatial analysis identified 14 clusters (RR=1.05-1.62) with statistical significance.Temporal analysis revealed that there were clusters between 2005 and 2009 in terms of the notification data on TB cases (RR=1.27,P=0.001).Spatio-temporal analysis identified 6 clusters (RR=1.19-3.55) with statistical significance.Counties and districts included in the first class cluster were similar by using the two different methods-spatial analysis and spatial-temporal analysis.Conclusions There is a descending trend of TB cases notification rates from western to eastern Zhejiang during the study period.The distribution of the TB case notified is not random at spatial, temporal and spatio-temporal levels.

Integrated detection and analysis on the dusters of schistosomiasis based on geographic information system / 中华流行病学杂志

Objective To detect and analyze the clusters of schistosomiasis on marshland and lake areas based on geographic information system (GIS) in 2008 and to provide suggestions for the development of integrated methodology on the detection of clusters on related diseases. Methods Moran' s I of global spatial autocorrelation, Getis-Ord Gi of local spatial autocorrelation and SaTScan were used to detect the schistosomiasis clusters based on GIS and comparison of the results for different methods were performed. Results Results from the global Moran' s I tests for all the marshland and lake areas related to the schistosomiasis were statistically significant (P＜0.05)and indicated spatial heterogeneity; the z-score outcomes as calculated by Getis-Ord Gi indicated high cluster that 50 clusters were categorized at the 0.05 significance level and the z-score of these 45 clusters were more than 0. Results of SaTScan statistics appeared the same as local spatial autocorrelation and almost showing the existence of 5 cluster areas. Conclusion The geographical distribution of clusters where schistosomiasis was prevalent showed that it was closely corresponded to the middle and lower Yangtse river and in particular, many clusters were located near the boundary of Hubei and Hunan province.

Spatial analysis on new smear-positive pulmonary tuberculosis in China, 2003-2008 / 中华流行病学杂志

Objective To analyze the notification status on new sputum-smear positive pulmonary tuberculosis (TB) over the recent years in China, and identify the clusters to address the related reasons. Methods To spatially and temporally scan the data regarding notification, and to display the results via geographic information system. Results (1) Spatial analysis identified 6clusters and their relative risks ranged from 1.03 to 1.83 with statistical significance; (2) Temporal analysis identified there were clusters between 2005 and 2007 in terms of notification on new sputum-smear positive pulmonary TB, and the relative risk was 1.27 (P=0.001); (3) Spatial and temporal analysis identified 2 clusters and the relative risks of the first class cluster and the second class cluster were 1.35 and 1.49 respectively with statistical significance. Provinces included in the first class cluster were basically the same as these in spatial analysis. Conclusion Distribution of the notification on new sputum-smear positive pulmonary TB was not stochastic at space, time and space-time, and clusters did exist in China.