Objective To investigate the epidemiological characteristics of varicella in Jiulongpo District, Chongqing from 2015 to 2024, and to provide a theoretical basis for the formulation of scientific prevention and control measures.

Methods The data on reported varicella cases in Jiulongpo District, Chongqing from 2015 to 2024 were collected. Descriptive epidemiological methods were used to describe its temperal‑spatial‑demographic distribution. And the Holt-Winters multiplicative model was used to predict the number of varicella cases from January to June 2025.

Results A total of 10 618 cases of varicella were reported from 2015 to 2024 in Jiulongpo District, with no death case. The annual incidence ranged from 54.20/100 000 to 132.98/100 000, with an average annual incidence rate of 85.88/100 000. The incidence of varicella showed a bimodal seasonal distribution, with a major peak occurring from October to December and a secondary peak from May to June. The male-to-female ratio of cases was 1.11∶1. Most cases occurred among students aged 5‒14 years. Cases were reported in all townships, with the top three areas in terms of incidence being Yangjiaping street, Huangjueping, and Huayan Town. All varicella-related public health emergencies occurred in schools, primarily during May‒June and October‒December, consistent with the overall temporal and demographic distribution of cases. The results of Holt-Winters multiplicative model showed that the number of cases from April to June 2025 was 52, 34, 43, 69, 105 and 108, respectively. Among children aged 1‒14 years, the average annual vaccination rate of the first dose of varicella vaccine was 12.03%, showing an initial rise followed by a fluctuating decline (P<0.001), while annual averaged vaccination rate for the second dose was 8.06%, showing a fluctuating upward trend (P<0.001).

Conclusion From 2015 to 2024, the reported incidence rate of varicella in Jiulongpo District was higher than the national average. The incidence of varicella showed a bimodal seasonal distribution and mainly affected students aged 5‒14 years old. At present, the vaccination coverage remains low, insufficient to form an effective herd immunity. The incidence of varicella is predicted to gradually increase between April and June 2025. It is necessary to further strengthen prevention and control measures in key settings such as schools and among student populations, enhance vaccination promotion to improve coverage rates, and utilize national pre-warning software and the Chongqing intelligent epidemic prevention and control system to improve surveillance sensitivity and prevent the occurrence of public health emergencies.