CAJ | 학술논문

目的探讨学校水痘暴发疫情的流行病学特征、传播因素和扩散方式,明确疫情控制的难点.方法根据现场流行病学调查方法和步骤,确定病例定义并完成病例搜索,描述病例三间分布特征,重点分析可能的传播因素与该起疫情间的关系,采用回顾性队列研究探讨相关传播因素.结果该起水痘暴发的总罹患率为4.4％(122/2742),小学生罹患率(8.3％,118/1419)明显高于初中生(0.3％,4/1323),但小学生罹患率的性别差异无统计学意义.疫情波及全校9个年级22个班,罹患率最高的是五年级(23.7％)和三年级(13.4％),呈现明显的班级聚集性.该起疫情为人与人接触传播,共持续72 d,出现4个发病高峰.“军训”促成疫情在首发病例的班级内传播,而疫情期间全校组织学生健康体检,又引发疫情的跨年级传播；未及时有效的落实隔离措施,是该起水痘在班级内传播的原因,但参加校外辅导班和乘坐社区免费接送车与疫情扩散的关联无统计学意义.该起疫情突破性水痘病例占所有病例的52.5％(64/122),病例均接种过一剂次水痘减毒活疫苗(VarV),从接种到发病的时间中位数为7年,接种疫苗与病程的差异无统计学意义,提示可能由于VarY剂次不足或接种疫苗年限较长而引发疫情.结论水痘暴发是学校重要的突发公共卫生事件.隔离措施难于落实,且跨班级的疫情传播链一旦形成,一般性的控制措施很难在短时间内显效.
목적 탐토학교수두폭발역정적류행병학특정、전파인소화확산방식,명학역정공제적난점.방법 근거현장류행병학조사방법화보취,학정병례정의병완성병례수색,묘술병례삼간분포특정,중점분석가능적전파인소여해기역정간적관계,채용회고성대렬연구탐토상관전파인소.결과 해기수두폭발적총리환솔위4.4％(122/2742),소학생리환솔(8.3％,118/1419)명현고우초중생(0.3％,4/1323),단소학생리환솔적성별차이무통계학의의.역정파급전교9개년급22개반,리환솔최고적시오년급(23.7％)화삼년급(13.4％),정현명현적반급취집성.해기역정위인여인접촉전파,공지속72 d,출현4개발병고봉.“군훈”촉성역정재수발병례적반급내전파,이역정기간전교조직학생건강체검,우인발역정적과년급전파；미급시유효적락실격리조시,시해기수두재반급내전파적원인,단삼가교외보도반화승좌사구면비접송차여역정확산적관련무통계학의의.해기역정돌파성수두병례점소유병례적52.5％(64/122),병례균접충과일제차수두감독활역묘(VarV),종접충도발병적시간중위수위7년,접충역묘여병정적차이무통계학의의,제시가능유우VarY제차불족혹접충역묘년한교장이인발역정.결론 수두폭발시학교중요적돌발공공위생사건.격리조시난우락실,차과반급적역정전파련일단형성,일반성적공제조시흔난재단시간내현효.
Objective Both epidemiologic characteristics and transmission mode of a varicella outbreak among schoolchildren in Shenzhen city were studied and related control measures were discussed.Methods Case definition was established.Case-finding and face-to-face investigation were conducted,followed by analysis on distributions of time,place and persons of the outbreak.Association between possible modes of transmission and the outbreak was explored.Retrospective cohort study was carried out.Results The overall attack rate of this outbreak was 4.4％ (122 of 2742).The attack rate among primary schoolchildren (8.3％,118/1419) was higher than that in the middle-school children (0.3％,4/1323).There were no statistically significant differences on the attack rates between male and female students.A total of 22 classes from the 9 grades were affected by this outbreak and the aggregation of varicella cases was found in classes.The highest attack rates was found in the students of fifth grade (23.7％),followed by from the third grade (13.4％).The main transmission mode appeared to be close personal contact.The outbreak,with four peaks of incidence,lasted 72 days.Data from the investigation suggested that the primary case was introduced into the school during military training involved by the students.Activities related to physical examination for all the schoolchildren seemed to have contributed to the spread of this disease among classes.Delayed isolation of cases appeared to be the major factor causing the spread of disease among classes.Intensive off-school activities or free community bus for children did not seem to be associated with the spreading of the disease.52.5％ (64/122) of the cases had received one-dose of varicella vaccine,with the median of onset after the vaccination as 7 years.The results demonstrated that one single-dose vaccine or long vaccination period were factors related to the insufficient immunity that causing the outbreak of disease.Conclusion Varicella outbreak has been one of the most grievous public health problems in schools,posting challenges on the implementation of isolation measures,in particular.Once the chain of transmission is in place,it is difficult to make the universal measures effective within a short period.