广东省甲型H1N1流感重症和死亡病例流行病学分析

Epidemiologic features of the severe and dead cases of influenza A(H1N1) in Guangdong Province

目的通过分析广东省甲型H1N1流感重症和死亡病例的流行病学特征,为评价甲型H1N1流感的危害程度,控制甲型H1N1流感提供科学依据。方法采用描述性流行病学方法,分析中国疾病预防控制中心甲型H1N1流感信息管理系统上报的广东省2009年甲型H1N1流感重症和死亡病例的流行病学特征、基础疾病、临床治疗、死亡原因等资料。结果广东省自2009年5月18日报告首例甲型H1N1流感病例至2009年12月31日,共报告甲型H1N1流感病例9 784例,重症、危重病例痊愈出院(以下统称重症病例)451例,死亡病例36例。根据报告病例数分析,重症发生率为4.61%,病死率为0.37%。第31周报告首例重症病例(报告时间为8月8日)后,第44周开始有报告重症和死亡病例(首例死亡病例报告时间为11月14日),第47周达到报告高峰(报告重症病例162例和死亡病例9例),之后逐渐下降,第52周回落到20例以下。发病数、重症病例数、死亡病例数以低年龄组为主,30岁以下的人群分别占93.3%(9 131/9 784)、82.9%(374/451)、69.4%(25/36)。重症发生率和病死率以高年龄组比较高,50岁以上的重症发生率为16.8%(22/131),病死率为5.3%(7/131)。20.4%(92/451)的重症病例和36.1%(13/36)的死亡病例有慢性基础疾病,主要为肺部疾病、心血管疾病和代谢性疾病等。75.4%(340/451)的重症病例和91.7%(33/36)的死亡病例出现并发症,排在前3位的直接死因为呼吸衰竭(占25.0%)、重症肺炎和多器官衰竭(均占13.9%)。79.4%(358/451)的重症病例和83.3%(30/36)的死亡病例曾使用达菲(神经氨酸抑制剂)进行治疗。结论重症发生率和病死率分析表明广东省甲型H1N1流感病毒的流行株比较温和,引起的严重疾病比较少。高年龄组人群发病容易发生重症和死亡,是预防控制重点。

Objective To analyze the epidemiological characteristics of the severe and dead cases,and to provide scientific basis for decreasing fatality rate and controlling influenza A（H1N1）.Methods Severe and dead cases of influenza A（H1N1） which reported from Guangdong Province in 2009 were analyzed for the epidemiological characteristics,primary diseases,clinic therapy and dead causes,with epidemiological methods.Results A total of 9 784 cases of influenza A（H1N1） were accumulatively reported in Guangdong Province in 2009.The number of severe but cured cases were 451 with morbidity rate of 4.61%,and the number of deaths were 36 with the fatality rate of 0.37%.The severe case firstly occurred in 31st week（8th August）,reoccurred in 44th week,reached to its peak in 47th week,162 severe cases and 9 death cases were reported,and gradually decreased less than 20 cases after 52nd week.The morbidity rate,and numbers of severity cases and death cases were dominated by younger age group,with the rates of 93.3%（9 131/9 784）,82.9%（374/451）and 69.4%（25/36）respectively,under 30 year-old age group.In elder age groups,incidence of severe cases and dead cases were higher.In patients older than 50,rates of severe cases reported and fatality rate were 16.8%（22/131）and 5.3%（7/131）.20.4%（92/451）of severe cases and 36.1%（13/36） of dead cases had primary chronic diseases,such as pulmonary diseases,cardiovascular diseases,and metabolic diseases.75.4%（340/451）of severe cases and 91.7%（33/36）of dead cases had severe complications,which top three ranks were respiratory failure,severe pneumonia and multiple organ failure.79.4%（358/451）of severe cases and 83.3%（30/36）of dead cases were treated with oseltamivir.Conclusion The prevalence showed that influenza A（H1N1） was mild and inducing less severe diseases.It is key point to control infection as the older age group were prone to severity and death.