中文摘要：

目的了解重庆地区急性下呼吸道感染（ALRTI）住院患儿人偏肺病毒（hMPV）感染的流行病学特点和临床特征。方法收集2006年4月至2008年3月重庆医科大学附属儿童医院呼吸科病房每周一、三、五因ALRTI住院患儿住院当日白天的鼻咽吸取物（NPA）,采用荧光定量PCR方法检测hMPV基因组RNA,阳性标本采用传统PCR方法扩增F基因,进一步确定是否存在hMPV感染,扩增G基因用于遗传进化分析。同时采用传统PCR方法检测呼吸道合胞病毒（RSV）和冠状病毒NL-63（HCoV-NL63）,直接免疫荧光法（DFA）检测流感病毒A、B亚型,副流感病毒1、2、3型和腺病毒。分析hMPV感染的流行病学特点和临床特征。结果研究期间共收集878份标本,占同期ALRTI入院病例的13.9%（878/6296例）。hMPV阳性227/878例（25.9%）。男∶女为1.9∶1。hMPV阳性227例中,〈6个月119例（52.4%）,～2岁72例（31.7%）,～6岁34例（15.0%）,〉6岁2例（0.9%）。hMPV流行特点为全年散发,好发季节为冬春季。hMPV阳性率2006年4月至2007年3月为18.5%（72/390例）,2007年4月至2008年3月为31.8%（155/488例）。227例hMPV阳性患儿临床诊断以肺炎（148例,65.2%）和毛细支气管炎（65例,28.6%）为主。hMPV可与常见呼吸道病毒协同感染,其中与RSV协同感染率最高（41.9%,95/227例）。遗传进化分析显示,研究期间重庆地区hMPVA和B基因型均流行,以A2亚型为优势株。结论 hMPV是重庆地区ALRTI住院患儿重要的呼吸道病毒病原之一,以〈6个月婴儿为主要感染人群。

英文摘要：

Objective In this study,the demographic and clinical characteristics associated with human metapneumovirus（hMPV）infection in children were investigated.Methods Nasopharyngeal aspirate specimens were collected over a 2-year period from children hospitalized with acute lower respiratory tract infections（ALRTI）and analyzed for the presence of hMPV infection using real-time chain reaction assay.To verify the presence and reproducibility of the virus,traditional RT-PCR primers 450F and 450R were used to amplify the hMPV F gene to ensure reproducibility.GF and GR primers were used to amplify the hMPV G gene and the sequences were used for phylogenetic analysis.All hMPV-positive samples were further tested for respiratory syncytial virus（RSV）and human coronavirus NL63（HCoV-NL63）with PCR.Some samples were sent for testing common respiratory viruses,including influenza A and B viruses,human parainfluenza virus types 1-3 and adenovirus with direct immunofluorescence assay（DFA）.Nucleotide sequences of the amplified G gene PCR products were aligned and phylogenetic trees were constructed by the neighbor-joining method.Clinical data were recorded and analyzed.Results Specimens from 878 patients（13.9% of the all ALRTI patients）were collected.The presence of hMPV was detected in 227（25.9%）of 878 children and hMPV may circulate year-round in the area,by the peak appeared during the winter-spring season.The male/female ratio was 1.8∶1.One hundred nineteen（52.4%）patients were younger than 6 months old,72 cases（31.7%）were from 6 months to 2 years old,34 cases（15.0%）were 2-6 years old,and 3 cases（0.9%）were over 6 years old.The median of age at diagnosis as hMPV infection was（11.5±15.6）months,and younger children（aged under 6 months）had the highest positivity.Infections caused by hMPV showed similar epidemiological and clinical manifestations as respiratory syncytial virus（RSV）and hMPV infection were related to wheezing,asthma exacerbations or bronchiolitis.Serious underlying