重庆永川地区急性呼吸道感染儿童呼吸道合胞病毒G基因变异分析

Analysis on variation of G gene of respiratory syncytial virus in children with acute respiratory tract infections at Yongchuan area of Chongqing City

目的分析重庆永川地区急性呼吸道感染儿童呼吸道合胞病毒（RSV）的分子流行病学特点。方法前瞻性收集2007年10月—2009年10月在本院儿科住院的急性呼吸道感染患儿的鼻咽深部吸取物标本385份,采用RT-PCR方法检测标本中RSV并分型。随机抽取8株A亚型RSV和6株B亚型RSV进行G蛋白全基因组测序。结果 385例患儿呼吸道标本中RSV阳性115例,阳性率为29.9%（115/385）,其中A亚型阳性98例（85.2%）,B亚型阳性17例（14.8%）。RSV阳性的115例患儿中,临床诊断依次为毛细支气管炎34例（29.6%）,支气管肺炎29例（25.2%）,间质性肺炎24例（20.9%）,喘息性支气管炎16例（13.9%）,支气管哮喘12例（10.4%）。G基因测序结果显示8株A亚型野生株与A亚型标准株A2间有显著性差异,野生株和A2株间的核苷酸同源性为91.2%~93.8%,氨基酸的同源性为84.0%~85.2%。A亚型野生株间的核苷酸同源性为93.6%~98.7%,氨基酸同源性为91.7%~99.0%。6株B亚型野生株与CH18537株的核苷酸同源性为81.4%~93.0%,氨基酸的同源性为79.3%~90.2%。B亚型野生株间的核苷酸同源性为87.8%~98.4%,氨基酸同源性为84.5%~97.1%。结论 RSV是永川地区婴幼儿急性呼吸道感染的重要病原,以A亚型流行为主。B亚型RSV的G基因变异较A亚型大。

Objective It is to analyze the molecular epidemiology characteristic of respiratory syncytial virus（RSV） in children with acute respiratory tract infections（ARTI） at Yongchuan area of Chongqing City.Methods 385 portions of nasopharyngeal aspirate specimens were collected from children with ARTI in department of pediatrics of our hospital from December 2007 to December 2009.RSV in those specimens was detected with RT-PCR method and divided typing.8 strains of subgroup A RSV and 6 strains of subgroup B RSV were randomly collected to carry out sequencing for G gene.Results Out of 385 portions of respiratory specimens,115 portions（29.9%） were positive for RSV.There were 98 portions（85.2%） positive subgroup A and 17 portions（14.8%） positive subgroup B in 115 portions of positive specimens.In 115 RSV positive patients,clinical diagnosis included 34 cases of bronchiolitis（24.9%）,29 cases of bronchopneumonia（25.2%）,24 cases of interstitial pneumonia（20.9%）,16 cases of asthmatoid bronchitis（13.9%） and 12 cases of bronchial asthma（10.4%）.G gene sequencing results showed that there was significant difference between 8 strains of subgroup A wild strain and subgroup A type strain A2.Between wild strain and A2 strain,the homology of nucleotide was 91.2%~93.8% and the homology of amino acid was 84.0%~85.2%.Among subgroup A wild strains,the homology of nucleotide was 93.6%~98.7% and the homology of amino acid was 91.7%~99.0%.Between 6 strains of subgroup B wild strain and CH18537 strain,the homology of nucleotide was 81.4%~93.0% and the homology of amino acid was 79.3%~90.2%.Among subgroup B wild strains,the homology of nucleotide was 87.8%~98.4% and the homology of amino acid was 84.5%~97.1%.Conclusion RSV is an important causative agent for acute respiratory tract infections in children in Yongchuan area.Subgroup A viruses are the main part of popular.The G gene variability of subgroup B RSV is higher than that of subgroup A RSV.