中文摘要：

目的了解苏州地区5岁以下严重急性呼吸道感染（severeacuterespiratoryinfection，SARI）住院患儿的病毒病原学构成、季节分布和临床特征，为苏州地区SARI病例的临床诊断治疗及防控提供线索和依据。方法对2011年3月至2012年2月期间在苏州大学附属儿童医院内科急诊病房及呼吸科病房住院治疗的5岁以下SARI病例采集鼻咽部分泌物进行实验室检测，同时收集患儿的既往病史及临床特征等相关信息。结果共纳入SARI病例746例，其中474例采集了鼻咽部分泌物。病毒阳性检出率为46.0％，其中流感病毒A型2．1％、B型11．0％、呼吸道合胞病毒（respiratorysyncytialvirus，RSV）26．6％、腺病毒3．2％、副流感病毒Ⅰ型2．7％、Ⅲ型4．0％，未检测到副流感Ⅱ型病毒。RSV全年均有流行，流感A、B型病毒则主要在冬、春季流行。男性患儿RSV阳性率高于女性患儿（P〈0．05）；流感病毒、RSV、腺病毒、副流感病毒在不同年龄段SARI患儿的阳性率差异皆有统计学意义（P〈0．05）。病毒检测阳性患儿咳嗽、喘息及肺炎的发生率显著高于阴性患儿（P〈0．05）；RSV及副流感病毒在肺炎患儿中的检出率明显高于其他诊断（p〈0．05）。纳入研究的SARI患儿平均住院天数7．38天，中位数为7天。SARI患儿在病程中接受糖皮质激素治疗与住院时间密切相关。结论苏州地区5岁以下SARI住院患儿病毒检出率最高的是．RSV和流感病毒，病毒感染可能是加重SARI病例临床症状的原因之一；不同病毒感染所致疾病特征有所差异，流感病毒以上呼吸道感染和肺炎为主，RSV以毛细支气管肺炎为主。

英文摘要：

Objective To understand the viral pathogens, seasonal distribution and clinical characteristics of children with severe acute respiratory infection （SARI） and admitted to Childrenr s Hospital in Suzhou,China, so as to provide clues for the clinical diagnosis, treatment, prevention and control of SARI eases. Methods Study was conducted from March 2011 to February 2012 in SARI children whom below 5 years and hospitalized in respiratory and emergency wards in Children＇s Hospital. We sampled the children＇s nasopharyngeal aspirate specimens for laboratory tesnng. Meanwhile, we collected their medical history and clinical characteristics. Results In total, 746 SARI cases were included and 474 cases were sampled and analyzed. The total positive rate of viruses was 46.0 %. The positive rate of influenza A was 2.1%, influenza B 11. 0%, respiratory syncytial virus （RSV） 26. 6%, adenovirus （ADV） 3. 2%, parainfluenza virus Ⅰ （PIVⅠ） 2. 7%, and PIVⅢ 4. 0%. No PIV Ⅱ case was detected. RSV infection was epidemic throughout the year, and the epidemic seasons of influenza A and B were winter and spring. The positive rate of RSV in males was higher than in females （P〈0. 05）;the positive rate of influenza,RSV, adenovirus,parainfluenza virus were significantly different among different age groups （P 〈 0. 05）. The incidence of cough, gasper and pneumonia were different between the positive and negative cases （P〈0.05）, and the incidence was relatively higher m positive ones. The positive rates of RSV or PIV were higher than other diagnoses （P〈0.05）. The mean and median duration of hospital stay for SARI was 7.38 days and 7 days,respectively. Receiving glucocorticoid therapy in the course of the disease was closed related to the length of hospital stay. Conclusions RSV and influenza were the most predominant pathogens in children under 5 years with SARI in Suzhou, and viral infection may be aggravated clinical symptoms of SARI cases. Different viral infections had different clinical fe