2009—2011年珠海市甲型H1N1流感流行特征分析

Analysis of prevalent features of influenza A(H1N1) in Zhuhai City,2009—2011

目的分析珠海市甲型H1N1流感的流行特征,为采取相应的防控措施提供科学依据。方法在珠海市设立28家流感样病例监测点、14家流感病原学监测点和8家肺炎住院病例监测点组成的监测网络,收集门诊就诊流感样病例及肺炎住院病例的监测数据及调查资料,对采集的标本使用逆转录聚合酶链式反应法进行甲型H1N1流感病原学检测,并采用描述性流行病学方法分析珠海市甲型H1N1流感的流行特征。结果 2009年6月至2011年5月珠海市流感监测系统共报告门诊流感样病例173 451例,其中检测3 598例,确诊甲型H1N1流感病例531例,占受检流感样病例的14.76%(531/3 598);肺炎住院病例监测点共报告门诊流感样病例41 852例,符合条件的肺炎住院病例1 006例,检出甲型H1N1流感病例共41例,其中死亡1例。门诊确诊甲型H1N1流感病例中男性302例,女性229例;不同年龄组中,0～10岁组占门诊确诊病例数的77.21%(410/531),11～20岁组占17.51%(93/531),样本中检出甲型H1N1流感病毒阳性率最高年龄组为11～20岁组(37.35%,93/249)和21～30岁组(16.67%,17/102);在职业分布上,甲型H1N1流感病毒阳性率最高分别为学生30.65%(213/695)、幼托儿童15.04%(186/1 237);甲型H1N1流感病毒检出率在2009年9—12月出现高峰,各月依次分别为29.32%(78/266)、31.37%(48/153)、60.70%(139/229)、40.63%(45/160),甲型H1N1流感病例数与流感样病例数两者存在线性正相关关系,其复相关系数为0.51(P<0.05);甲型H1N1流感病例的发病就诊间隔时间平均为0.11 d,其临床表现主要为发热(100.00%,531/531)、咳嗽(60.83%,323/531)、咽痛(56.31%,299/531),肺炎仅占1.13%(6/531);观察期内估算甲型H1N1流感发病就诊人数达14.42万,住院率为0.66%。结论珠海市甲型H1N1流感病例以轻症为主,发病高峰在2009年9—12月,发病人群以儿童和青少年为主。

Objective To analyze the epidemiological characteristics of pandemic influenza A （H1N1） in Zhuhai City, and provide a scientific basis for prevention and control. Methods We established 28 influenza-like illness （ILI） sentinels, 14 influenza pathogen surveillance sites and 8 pneumonia inpatients sentinels in Zhuhai City to collect data of ILl outpatients and was inpatients with pneumonia. The specimens were detected for influenza A （H1N1） pathogen by reverse transcriptase polymerase chain reac- tion method. We used descriptive epidemiological methods to analyze the epidemiological characteristics of the influenza A （H1N1）. Results A total of 173 451 ILI cases were reported and 3 598 cases was detec- ted, and 531 influenza A （H1N1） cases （302 male, 229 female） were confirmed, accounting for 14.76%. 41 cases and 1 death were infected with A （H1N1） among 1 006 inpatients of pneumonia. The children aged below 10 years were accounted for 77.21% （410/531） of the out-patient number of con- firmed cases, 11 - 20 year - old group accounted for 17.51% （93/531 ）. The prevalence of H1 N1 influen- za virus infection in 11 - 20 and 21 - 30 age groups was the highest, accounted for 37.35% （93/249） and 16.67% （17/102）. On the occupational distribution the positive rate followed by students 30. 65% （ 213/695 ） , kindergarten children 15.04% （ 186/1 237 ）. The isolation rates of influenza A （ H1 N1 ） were 29.32% （78/266）, 31.37% （48/153）, 60.70% （ 139/229）, and 40.63% （45/160） from September to December 2009, respectively. The number of cases of influenza A （ H1N1 ） and ILI were linear positive- ly correlated, and the multiple correlation coefficient was 0.51 （P 〈 0.05 ）. The average interval between the onset and seeking medical treatment for influenza A （H1N1） was 0.11 day. Respiratory symptoms as the main symptoms of the clinical manifestations were fever （100.00%, 531/531 ） , cough （60.83% , 323/531 ） , sore throat （56.31% , 299,/531 ）, and other respiratory symptoms. Pneumonia was accounted for only 1.13% （6/531）. During observation period, it was estimated that 144 200 patients sought medical service for influenza A （ H1 N1 ）, with a hospitalization rate of 0.66%. Conclusion The cases of influenza A （H1N1） were symptomatically mild. The onset peak of pandemic influenza A （H1N1） was from September to December 2009 in Zhuhai City. Children and adolescents were the main population in all influenza A （H1N1） cases.