[Analysis of epidemiological characteristics of bacillary dysentery with multiple-onset in Henan Province from 2005 to 2020]

Objective: To understand the epidemiological characteristics of bacillary dysentery with multiple-onset in Henan province from 2005 to 2020. Methods: The reported cases of bacillary dysentery (including confirmed cases and clinically diagnosed cases) in Henan Province from January 2005 to December 2020 were collected through China’s National Disease Supervision Information Management System. The main information included gender, age, home address, date of onset and date of diagnosis. The interval between two episodes of the same case was more than 15 days, which was judged as two episodes. The incidence characteristics of bacillary dysentery patients with two or more cases in Henan Province from 2005 to 2020 were analyzed, and the regional distribution map of cases was drawn using ArcGIS software. Results: From 2005 to 2020, a total of 250 430 cases of bacillary dysentery were reported in Henan Province, with a cumulative incidence rate of 228.66/100 000. There were 2 342 cases with two or more attacks. The incidence of recurrent cases of bacillary dysentery increased year by year (χ^{2}_{trend}=2 932.28, P <0.001). There was no significant difference in the incidence of two or more cases of different sexes (χ^{2}=0.39, P =0.540). There was significant difference in the incidence among different age groups (χ^{2}=438.40, P <0.001). The incidence of two or more cases in the 60-69 age group was relatively high (1.70%). The shortest time interval between the onset of the disease was 16 days, and the longest was 5 579 days, with M ( Q _{1}, Q _{3}) about 428 (237, 843) days. Compared with healthy people, those with a history of bacterial diseases had a higher risk of developing bacillary dysentery ( RR : 4.12, 95% CI : 3.95‒4.29). Conclusion: The proportion of patients with multiple-onset shows an increasing trend, and there is an age difference.