1. Changchun Center for Disease Control and Prevention (Changchun Institute of Public Health Supervision), Changchun, Jilin 130018, China; 2. Jilin Provincial Center for Disease Control and Prevention (Jilin Provincial Academy of Preventive Medicine), Changchun, Jilin 130062, China
Abstract：Objective To investigate the epidemiological characteristics and spatial-temporal clustering of varicella in Changchun City from 2020 to 2024, so as to provide the evidence for formulating local varicella prevention and control measures. Methods The individual case data of varicella were collected through the Surveillance and Reporting Management System of the Chinese Disease Prevention and Control Information System in Changchun City from 2020 to 2024. Descriptive epidemiological methods were used to analyze the population ,regional, and temporal distribution. Spatial autocorrelation and spatio-temporal scanning analyses were used to identify the spatial-temporal clustering characteristics. Results A total of 8 850 varicella cases were reported in Changchun City from 2020 to 2024, with an average annual incidence of 19.64/105. There were 4 929 male cases and 3 921 female cases, with a male-to-female ratio of 1.26∶1. The age was mainly 0-<20 years (6 649 cases, 75.13%), and students were the predominant occupation (6 036 cases, 68.20%). The top three counties (cities, districts) with the highest number of cases were Chaoyang District (1 944 cases), Gongzhuling City (1 054 cases) and Nanguan District (987 cases), accounting for 45.03%. The peak incidence periods were from April to June and from October to December, with 2 166 and 4 226 cases, accounting for 24.47% and 47.75%, respectively. Spatial autocorrelation analysis showed that spatial clustering existed from 2020 to 2024. The high-high clustering areas were mainly some townships (streets) in Chaoyang District, Nanguan District, Changchun New District and Jingyue District. Spatio-temporal scanning analysis identified 6 high-risk clustering areas. The class Ⅰ clustering area was Nanhu Street in Chaoyang District, with the clustering period from September 2020 to February 2022. Conclusions Varicella cases in Changchun City were mainly males and students aged 0-<20 years from 2020 to 2024. The peak incidence was mainly in winter. Chaoyang District was a high-risk area, with obvious spatial-temporal clustering.
