Abstract:Abstract: OBJECTIVE To explore the alterations in epidemiological characteristics during different immunization strategies in Jiangning District,thereby providing a scientific foundation for varicella vaccine vaccination and epidemic prevention and control. METHODS Data on varicella cases from 2016 to 2024in Jiangning District were collected from the China Disease Prevention and Control Information System and statistically analyzed using descriptive epidemiology.RESULTS The reported incidence rates during 2016—2018, 2019—2022,2023—2024 were 215.96/100,000,168.98/100,000,and 75.59/100,000respectively.The reported incidence rates exhibited a decline,and the difference was statisticallysignificant(x²=2,562.81,P<0.01).There was a seasonal “bimodal”distribution,and the peak decreased notably since 2020.The reported incidence rates of varicelladecreased significantly in seven streets(P<0.01).The reported incidence rate was significantly higher in males than in females.With the enhancement of immunization strategies,the median age of onset shifted by 3 and 7 years respectively,and the reported incidence rates decreased significantly in the age groups of 5 to 9 years old,10 to 14 years old,15 to 19 years old,20 to 24 years old,and 30 to 34 years old(P<0.01).CONCLUSION After the inclusion of the varicella vaccine in the immunization plan,the reported incidence rate of varicella decreased significantly.The free two dose inoculation of the varicella vaccine achieved remarkable outcomes,and the vaccination rate of children should be ensured.