JCNRJournal of Clinical and Nursing Research2208-36852208-3693Bio-Byword Scientific Publishing Pty. Ltd.10.26689/jcnr.v8i6.7633ArticleAnalysis of Epidemiological Characteristics of Varicella Before and After the Implementation of the Two-dose Varicella Vaccine Immunization Program in Banan District of Chongqing Cityhttps://artdesignp.com/journal/JCNR/8/6/10.26689/jcnr.v8i6.7633ChengYundan,YanJu,ZhuXiaoling,JiangXiaoxia,LiJingzhi,LengHao2024862024-07-18Objective: To explore the changes in the epidemiological characteristics of varicella before and after implementing the two-dose varicella vaccine (VarV) immunization program in the Banan District of Chongqing and to provide a reference for future epidemic prevention and control. Methods: The data of reported varicella cases in Banan District from 2014 to 2023 were collected and analyzed using the China Disease Prevention and Control Information System. Descriptive epidemiological methods were employed to assess the changes in the reported incidence of varicella before (2014–2018) and after (2019–2023) the implementation of the two-dose VarV immunization program. Results: The average annual reported incidence rate of varicella in Banan District from 2014 to 2023 was 81.53 per 100,000. From 2014 to 2018, the reported incidence rate showed an upward trend year by year (trend χ² = 223.96, P < 0.05). However, the reported incidence rate decreased from 2019 to 2023 (trend χ² = 189.51, P < 0.05). Before and after the adjustment of the immunization program, the reported incidence rate for the 5–9 years old group was 774.62 per 100,000 and 476.98 per 100,000, respectively, with a statistically significant difference (χ² = 161.26, P < 0.05). The onset of varicella showed a bimodal distribution, with peak incidence periods in May–June and October–December. From 2014 to 2023, a total of 155,181 doses of VarV were administered in Banan District. The estimated annual vaccination rate for the first varicella vaccine (VarV1) from 2019 to 2023 was 86.28%, and for the second dose (VarV2) was 59.18%. The primary vaccination targets were the 5–9-year-old group, accounting for 64.21%. Conclusion: After implementing the two-dose VarV immunization program in Banan District, the vaccination rate increased yearly, and the reported incidence of varicella showed a downward trend. The incidence rate of varicella in children aged 5–9 years reduced significantly, but the overall downward trend for the entire population was not as pronounced. Therefore, it is necessary to increase the vaccination rate of VarV2.

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