Spatial-temporal analysis of pulmonary tuberculosis in Shandong province, 2015

Abstract

Objective: To analyze the spatial-temporal epidemiological characteristics of active pulmonary tuberculosis (PTB) and sputum smear positive (SS+) PTB in Shandong province, China, 2015. Methods: The surveillance data of active PTB and SS+PTB in Shandong in 2015 were collected and analyzed by using the global and local indicators of spatial association (Moran's I) for the spatial autocorrelation of PTB, and by using SaTScan forspatial-temporal clustering characteristics of PTB based on geographic information system. Results: Totally, 31 776 active PTB cases and 8 631 SS+PTB cases were reported in Shandong in 2015, and the reported incidence rates of active PTB and SS+PTB were 33.09/100 000 and 8.99/100 000, respectively. Active PTB had positive spatial autocorrelation at county level, and the value of Moran's I value was 0.219 (P<0.001), indicating that the high-high (HH) aggregation areas with high incidence were in the northwestern, southeastern and central southern Shandong; SS+PTB also had positive spatial autocorrelation at county level, and the value of the Moran's I was 1.178 (P<0.001), indicating that the HH aggregation areas with high incidence were in the southeastern and northwestern Shandong. The results of spatial-temporal scanning indicated that there was incidence clustering of active PTB in the second quarter and the third quarter in 2015, and the clustering areas were in the central southern, southeastern and northwestern Shandong; there also was incidence clustering of SS+PTB in the second quarter and the third quarter in 2015, and the clustering areas were in the southeastern and northwestern Shandong. Conclusions: The incidence of active PTB and SS+PTB showed spatial and temporal clustering in Shandong in 2015. The areas with high PTB burden and high PTB transmission risks were in the northwestern and southeastern Shandong. The areas with high PTB burden but without high PTB transmission risks were in the central southern Shandong.