海南省2011—2015年度流感暴发疫情流行病学特征分析

Epidemiological characteristics of influenza outbreaks in Hainan, 2011-2015

目的分析海南省2011—2015年度流感暴发疫情的流行病学特征,为流感防控提供科学依据。方法收集2011—2015年度全省报告的流感暴发疫情资料,对暴发的时间、地区、场所、规模、病毒型别进行描述性流行病学分析。结果 2011—2015年度全省共报告流感暴发疫情21起,累计报告发病791例,平均罹患率3.17%,无死亡病例。暴发疫情主要发生在每年的3月和5月,占总起数的76.19%,疫情主要集中在中小学校,共20起(占总起数的95.24%)。农村地区报告疫情起数最多,占总起数的71.43%。暴发的优势循环株先后为B型流感,甲型H1N1流感,甲型H3N2亚型和B型流感。结论海南省流感暴发疫情具有明显的季节性,春季是高发季节,中小学校是流感暴发的高发场所,应加强农村学校流感样病例暴发疫情的监测,优势循环株变化频繁,应密切关注病原学变化。

Objective To investigate the epidemiological characteristics of influenza outbreaks in Hainan Province from2011 to 2015, in order to provide scientific evidence for control and prevention of influenza. Methods Epidemic data aboutinfluenza outbreak reported in Hainan during 2011 and 2015 were collected, and descriptive epidemiological analysis wasconducted to study the outbreak time, area, place, extent and the type/subtype of influenza virus. Results A total of 21 influenza outbreaks were reported in Hainan Province during the year of 2011 to 2015, including 791 cases, with an averageattack rate of 3.17%, and no death case was reported. The peak of the outbreaks was in March and May, accounting for 76.19%of the total. Outbreaks mainly occurred in primary and middle schools, and 20 outbreaks were reported there, accounting for95.24% of the total. Most of the outbreaks occurred in rural areas, taking up 71.43% of the total. The predominant influenzastrains were influenza B virus, influenza A（H1N1） virus, influenza A（H3N2） and B virus in turn. Conclusion Influenzaoutbreak is seasonal in Hainan Province, peaking in spring. Primary and middle schools are the main locations for itsoutbreaks. Surveillance should be strengthened for influenza-like outbreaks in schools, especially those in rural areas. Thepredominant virus strains vary frequently, and intensive attention should be paid.