Objective To analyze epidemiological characteristics and spatiotemporal clustering of varicella in Daxing district of Beijing, 2018−2024, and provide scientific evidence for more effective control of varicella.

Methods The incidence data of varicella in Daxing from 2018 to 2024 were collected from National Health Information System for Disease Prevention and Control. Software Excel 2019 and R 4.1.1 were used to analyze the varicella incidence data, and software Geoda was used for spatial autocorrelation analysis. SaTScan 10.1.3 was used for spatiotemporal scanning analysis.

Results A total of 5 290 varicella cases were reported during 2018−2024 in Daxing, the average annual incidence was 42.16/100 000. There was statistically significant difference in the incidence among different sub-districts (P<0.01). The overall incidence of varicella showed two seasonal peaks, with the main peak occurring during October-December and -subpeak in May. The top two age groups with high average annual reported incidence rate were age group 0～4 years (195.50/100 000) and age group 15～19 years (154.41/100 000). The cases were mainly students (26.86%), followed by home-cared children (17.64%). Among the varicella cases in students and preschool children, the proportion of the children with fever and moderate-to-severe rash were lower in those with vaccination history than in those without vaccination history (P<0.05). The global autocorrelation analysis indicated that the incidence of varicella showed spatial clustering in 2018 and 2020 (P<0.05). Local spatial autocorrelation analysis indicated the presence of "high-high" clustering areas in 2018, 2019, and 2024 in the northwestern area. Spatiotemporal scanning analysis detected ten clustering areas, of which claas I clustering area was in Guanyinsi from March 2018 to June 2019.

Conclusion From 2018 to 2024, the overall incidence of varicella in Daxing showed a declining trend. The incidence of the disease had area specific disparities and two seasonal peaks. The main populations at high-risk were students and home-cared children, and the cases were mainly distributed in age groups 0～4 years and 15～19 years. Furthermore, the children with vaccination history had milder clinical symptoms compared with those unvaccinated. The incidence of the disease had local spatial clustering in the district, which was mainly in the northwestern area. It is suggested to improve surveillance sensitivity and response timeliness for varicella in areas with high-incidence and key populations, and continuously strengthen vaccination promotion to increase the vaccination rate of age-eligible children.