Abstract: Objective To conduct a comprehensive analysis of the epidemiological characteristics of bacterial dysentery（BD） in Jiulongpo District of Chongqing from 2020 to 2023,identify high-risk areas spatially and temporally,so as to provide a basis for the monitoring,prevention and control of BD in Jiulongpo District. Methods The monthly incidence numbers of BD in Jiulongpo District of Chongqing from 2020 to 2023 were derived from the "China Disease Prevention and Control Information System". Descriptive epidemiological research methods were used to analyze the epidemiological characteristics of the disease,Joinpoint regression analysis was used to evaluate the trend of incidence rise and fall,circular distribution method was used to describe seasonal characteristics,and spatial autocorrelation and spatiotemporal scanning statistics were used to explore the spatiotemporal distribution of incidence. Results From 2020 to 2023,a cumulative total of 1 482 BD cases were reported in Jiulongpo District of Chongqing,with an average annual reported incidence rate of 24.27/100 000,and the incidence rate showed a downward trend year by year（APC=-20.30%,AAPC=-20.30%,95%CI：-24.90%- -16.19%,P<0.05）. There was significant seasonality from 2020 to 2022,with peak days mainly occurring from July to September,with the earliest peak appearing in April and the latest in December. The male to female sex ratio was 1.05 ∶ 1,and the incidence of the disease mainly affected diaspora children under 5 years old. From 2020 to 2023,the global spatial autocorrelation and local autocorrelation of BD incidence rate in Jiulongpo District of Chongqing City were statistically significant（both P<0.05）,and the High-High clustering pattern was mainly concentrated in Huangjueping Street,Yangjiaping Street,Shipingqiao Street and Xiejiawan Street. The spatio-temporal scanning analysis showed that the BD aggregation time in 2020 was from May to October,in 2021 it was from March to September,in 2022 it was from January to September,and in 2023 it was from January to July. Conclusion As a key prevention and control area for BD,Jiulongpo District in Chongqing should further create a good hygiene environment,carry out BD health education,improve diagnostic accuracy,and combine seasonal high incidence and disease spectrum characteristics to control the spread and prevalence of BD.

Key words: Bacillary dysentery, Epidemiological characteristics, Spatial autocorrelation, Spatiotemporal clustering