目的 分析《大英县中小学托幼机构水痘预防和控制工作方案(试行)》(简称《方案》)实施前后,大英县水痘发病、暴发疫情及疫苗接种的变化,评价2剂次水痘疫苗接种的作用。方法 通过收集中国疾病预防控制信息系统中2015—2022年报告的大英县水痘病例监测资料和暴发疫情现场流行病学调查相关资料,以及四川免疫规划管理信息系统中水痘疫苗接种资料,进行描述性流行病学分析。结果 2019年《方案》实施后,总接种剂次、第1剂、第2剂分别增加73.82%、10.96%、190.03%。2015—2022年大英县共报告水痘病例1 443例,年均报告发病率为45.12/10万。《方案》实施后,年均发病率下降62.45%(χ²=15.915,P＜0.001)。1~14岁年龄组儿童水痘发病率下降77.20%,其中5~9岁年龄组发病率下降幅度最大,为88.99%,15~24岁年龄组水痘发病率上升91.83%。暴发疫情总罹患率由1.35%下降至0.55%,每起疫情发病人数由9.50人下降至7.00人,每起疫情持续时间由33.00 d下降至23.50 d,每起疫情代次由1.57代下降至1.12代。结论 水痘2剂次接种程序对控制水痘发病及暴发疫情效果显著,继续实施2剂次水痘疫苗接种策略对水痘疫情控制具有重要意义。

Objective To analyze the changes in varicella incidence,outbreak and vaccination in Daying County before and after the implementation of the Plan for the Prevention and Control of Varicella in Primary and Secondary School Childcare Institutions (Trial) (hereinafter referred to as the Plan),and to evaluate the effect of two-dose inoculation of varicella vaccine. Methods The surveillance data of varicella cases in Daying County reported in the China Disease Prevention and Control Information System from 2015 to 2022,the relevant data of field epidemiological investigation and disposal of epidemic situation,and the data of varicella vaccination in the Sichuan Immunization Program Management Information System were collected to conduct descriptive epidemiological analysis. Results After the implementation of the Plan in 2019,the total dose,the first dose and the second dose increased by 73.82%,10.96% and 190.03%,respectively.From 2015 to 2022,a total of 1 443 cases of varicella were reported in Daying County,with an annual average reported incidence rate of 45.12/100 000.After the implementation of the Plan,the annual average incidence rate decreased by 62.45% (χ²=15.915,P<0.001).The incidence of varicella decreased by 77.20% in the age group of 1-14 years,of which the incidence rate of varicella in the 5-9 year old group decreased the most,88.99%,and the incidence of varicella increased by 91.83% in the age group of 15-24 years.The total incidence rate of varicella in outbreaks decreased from 1.35% to 0.55%,the number of patients per outbreak decreased from 9.50 to 7.00,the duration of each outbreak decreased from 33.00 to 23.50 days,and the number of generations per outbreak decreased from 1.57 to 1.12. Conclusion The two-dose varicella vaccination program is effective in controlling the occurrence and outbreak of varicella,and it is necessary to continue to implement the two-dose varicella vaccination strategy.