2015-2018年新乡地区儿童呼吸道感染病原特征分析

Etiological analysis of respiratory tract infections in children in the Xinxiang area from 2015-2018

目的分析2015-2018年新乡地区儿童呼吸道感染病原学,指导临床治疗。方法收集2015-2018新乡地区儿童呼吸道感染患者临床资料,采用间接免疫荧光方法检测患儿病原体IgM抗体,分析病原类型,同时观察临床指标。结果本研究共分离960株病原,2015-2018年各年度分别分离169、211、276和304株。其中,389株呼吸道合胞病毒、250株流感病毒、169株副流感病毒、71株腺病毒、81株其他病原,构成比分别为40.52%、26.04%、17.60%、7.40%、8.44%。春、夏、秋、冬四季分离的病原分别为332、152、187和289株,构成比分别为34.58%、15.83%、19.48%和30.10%。<1岁、1~岁及3~14岁患儿感染病原数分别为402、345和213株,构成比分别为41.88%、35.94%、22.19%。女性患儿分离627株,男性患儿分离333株,构成比分别为65.31%和34.69%。支气管肺炎、发热患儿、急性上呼吸道感染、肺炎、急性支气管炎和急性喘息性支气管炎感染病原数为416株(43.33%)、225株(23.44%)、148株(15.42%),83株(8.65%),57株(5.94%),31株(3.23%)。389株呼吸道合胞病毒中A亚型182株(46.79%),B亚型207株(5.21%)。A亚型中选取的40株测序结果显示:NA1基因型18株,ON1基因型15株,NA4基因型7株。B亚型中选取的40株测序结果显示:BA9基因型27株,BA7基因型8株,BA8基因型4株和BA10基因型1株。结论呼吸道合胞病毒是患儿感染的主要病原类型,并呈现逐年升高趋势。春冬季节是病原感染高峰期,<1岁女性患儿是感染高发人群。临床诊断为支气管肺炎的患儿感染病原数最多。呼吸道合胞病毒NA1基因型的变异特点是糖基化位点突变,ON基因型和NA4基因型发生核苷酸替换,这些突变可能是呼吸道合胞病毒免疫逃逸机制。

Objectives To analyze the etiology of respiratory tract infections in children in the Xinxiang area from 2015-2018 in order to guide their clinical treatment. Methods Clinical data on children with a respiratory tract infection in the Xinxiang district from 2015 to 2018 were collected. Indirect immunofluorescence was used to detect IgM antibodies in order to analyze the type of pathogen, and clinical indices were noted at the same time. Results A total of 960 pathogens were isolated. One hundred and sixty-nine strains were isolated in 2015, 211 were isolated in 2016, 276 were isolated in 2017, and 304 were isolated in 2018. The 960 pathogens included 389 strains of respiratory syncytial virus(40.52%), 250 strains of influenza virus(26.04%), 169 strains of parainfluenza virus(17.60%), 71 strains of adenovirus(7.40%), and 81 strains of other pathogens(8.44%). Three hundred and thirty-two strains of pathogens were isolated in the spring(34.58%), 152 were isolated in the summer(15.83%), 187 were isolated in the autumn(19.48%), and 289 were isolated in the winter(30.10%). Four hundred and two strains were isolated from pediatric patients under the age of 1(41.88%), 345 were isolated from pediatric patients ages 1-3(35.94%), and 213 were isolated from pediatric patients ages 3-14(22.19%). Six hundred and twenty-seven strains were isolated from female children(65.31%), and 333 were isolated from male children(34.69%). Four hundred and sixteen strains(43.33%) were isolated from pediatric patients with bronchopneumonia, 225(23.44%) were isolated from pediatric patients with a fever, 148(15.42%) were isolated from pediatric patients with an acute upper respiratory tract infection, 83(8.65%) were isolated from pediatric patients with pneumonia, 57(5.94%) were isolated from pediatric patients with acute bronchitis, and 31(3.23%) were isolated from pediatric patients with acute asthmatic bronchitis. Of 389 strains of respiratory syncytial virus, 182(46.79%) were subtype A and 207(5.21%) were subtype B. Sequencing of 40 of the subtype A strains indicated that 18 were the NA1 genotype, 15 were the ON1 genotype, and 7 were the NA4 genotype. Sequencing of 40 of the subtype B strains indicated that 27 were the BA9 genotype, 8 were the BA7 genotype, 4 were the BA8 genotype, and 1 was the BA10 genotype. Conclusion Respiratory syncytial virus is the main pathogen infecting pediatric patients, and the incidence of respiratory tract infections has tended to increase each year. Infections peak in the spring and winter, and female pediatric patients under the age of 1 are at risk of developing an infection. Pathogens were most prevalent in pediatric patients diagnosed with bronchopneumonia. Mutation in the NA1 genotype of respiratory syncytial virus was characterized by a glycosylation site mutation, while nucleotide substitution occurred in the ON genotype and NA4 genotype. These mutations may be the mechanism of immune evasion by the respiratory syncytial virus.