西安市2020年1起中学水痘暴发的流行特征和突破病例危险因素  

Epidemiological characteristics of a varicella outbreak and risk factors for breakthrough cases in a middle school of Xi’an city in 2020

作　　者：张辉[1] 雷媛 李倩[1] 王春娟[1] 李思瑶 陈志军[1] Zhang Hui;Lei Yuan;Li Qian;Wang Chunjuan;Li Siyao;Chen Zhijun(Xi'an Municipal Center for Disease Control and Prevention,Xi'an 710054,Shaanxi,China;Beilin District Center for Disease Control and Prevention,Xi'an 710000,Shaanxi,China)

机构地区：[1]西安市疾病预防控制中心,陕西西安710054 [2]西安市碑林区疾病预防控制中心,陕西西安710000

出　　处：《中国疫苗和免疫》2021年第6期673-677,共5页Chinese Journal of Vaccines and Immunization

摘　　要：目的分析西安市2020年1起中学水痘暴发疫情的流行病学特征和突破病例发病危险因素。方法对本起疫情开展水痘病例主动搜索和流行病学调查,描述性分析流行病学特征;采用病例对照研究分析水痘突破病例的危险因素。结果本起中学水痘暴发疫情持续65d,水痘总罹患率为1.84%(49/2 661),其中学生、教职工罹患率分别为2.06%(48/2 328)、0.30%(1/333)。高一、高二、高三年级学生罹患率分别为5.17%(42/812)、0.66%(5/759)、0.13%(1/757);0、1、2剂次水痘疫苗(VarV)免疫史学生罹患率分别为3.86%(14/363)、1.91%(32/1 679)、1.18%(2/170)。在学生中1剂次、2剂次VarV的疫苗保护率分别为50.52%(95%CI:45.55%-55.48%)、69.43%(95%CI:64.66%-73.82%)。学生水痘突破病例罹患率为1.84%(34/1 849)。住校、班内有其他病例、接种VarV年限≥9年、学校食堂就餐、仅接种1剂次VarV是突破病例的危险因素[OR(95%CI):3.08(1.12-8.47)、2.86(1.04-7.87)、3.13(1.20-8.18)、4.96(1.51-16.28)、6.79(1.45-31.80)]。结论本起中学水痘暴发主要与未及时发现病例和控制传播以及学生VarV保护水平下降有关;建议儿童入学前完成2剂次VarV接种。Objective To analyze epidemiological characteristics of a varicella outbreak and risk factors for breakthrough cases in a middle school of Xi’an city in 2020.Methods We conducted an active search of varicella cases in an epidemiological investigation of a varicella outbreak. We determined epidemiological characteristics of the outbreak and analyzed risk factors for breakthrough cases in a case-control study.Results The middle school varicella outbreak lasted for 65 days;the overall attack rate was 1.84%(49/2 661);attack rates were 2.06%(48/2 328) among students and 0.30%(1/333) among faculty. Attack rates for students in grades 1, 2, and 3 were 5.17%(42/812), 0.66%(5/759), and 0.13%(1/757);attack rates for students who received 0, 1, and 2 doses of VarV were 3.86%(14/363), 1.91%(32/1 679), and 1.18%(2/170). Vaccine effectiveness among students was 50.52%(95%CI: 45.55%-55.48%) for 1 dose of VarV and 69.43%(95%CI: 64.66%-73.82%) for 2 doses of VarV. The attack rate among students for breakthrough cases was 1.84%(34/1 849). Risk factors for breakthrough cases included living in the school, having other cases in classes, receiving VarV ≥9 years previously, eating in the school canteen, and receiving only 1 dose of VarV [OR(95%CI): 3.08(1.12-8.47), 2.86(1.04-7.87), 3.13(1.20-8.18), 4.96(1.51-16.28), and 6.79(1.45-31.80)].Conclusions The middle school varicella outbreak was associated with delayed detection and control of transmission of varicella virus and low vaccine effectiveness. We suggest that preschool children receive 2 doses of VarV.

关 键 词：水痘 暴发 流行病学特征 突破病例 危险因素 

分 类 号：R186[医药卫生—流行病学]