一起北京市某职业学院流感暴发疫情分析

Investigation of an influenza outbreak in a vocational college of Beijing

目的通过对北京市某职业学院一起流感暴发疫情进行调查和分析,为有效防控学校流感暴发疫情提供科学依据。方法采用现场流行病学调查方法,对北京市某职业学院流感暴发疫情中病例进行个案调查,采集发热病例咽拭子标本,采用Real-Time PCR方法检测流感病毒核酸,应用MDCK细胞分离流感病毒。结果 2015年12月25-29日期间,该学校共报告发热病例25例,均为一个班级学生,罹患率为52.08%。该起疫情持续5 d。现场采集13份现症病例的咽拭子标本,经检测均为乙型Victoria亚型流感病毒核酸阳性,其中7例成功分离到乙型Victoria亚型流感病毒阳性。结论此次疫情为乙型Victoria亚型流感病毒感染所致,呼吸道传播和密切接触传播均为可能的传播途径。流调人员采取以隔离传染源为核心的综合措施,未见续发病例,有效地抑制了该病的传播和扩散,疫情迅速得到控制。

Objective To analyze the epidemiological characteristics of an influenza outbreak in a vocational college of Beijing, so as to provide reference for the prevention and control of influenza outbreaks. Methods Epidemiological method was used to investigate the influenza outbreak in a vocational college. The throat swab samples were collected. Real-time PCR assay was applied to detect the influenza virus nucleic acid. The virus strains were isolated by Mad in-Darby Canine Kidney （MDCK） cell directly. Results 25studentswith fever were reported in the same class from 25 to 29 December, 2015, and the attack rate was 52. 08%. The outbreak lasted for 5 days. 13 samples were collected and were all positive for nucleic acid of influenza B Victoria. Furthermore, influenza B Victoria was cultured from seven samples. Conclusion The outbreak was caused by influenza B Victoria virus. Respiratory transmission and close contact were possible routes of infection. Comprehensive measures were taken such as isolation the source of infection, and no secondary infection were reported. Thus, the outbreak was effectively controlled.