2016-2018年兰州市某医院急性下呼吸道感染患儿RSV分离及流行病学特征分析

Isolation of RSV and epidemiologi calcharacteristics in children with acute lower respiratory tract infection from 2016 to 2018 in a hospital in Lanzhou City

目的对2016-2018年甘肃省妇幼保健医院门诊和住院急性下呼吸道感染患儿进行呼吸道合胞病毒(Respiratory syncytial virus, RSV)的分离及流行病学特征分析。方法收集患儿呼吸道分泌物425份,在Vero细胞上进行3代盲传,对培养收获液进行反转录聚合酶链反应(reverse transcription PCR, RT-PCR)检测及测序,将阳性样本进行序列对比和流行病学特征分析。结果 425份样本中阳性样本为143份,阳性分离率为33.6%。部分接种Vero细胞的样本与RSV典型病变一致。分离出RSV经过RT-PCR得到特异性扩增条带与预期设计的扩增片段大小相符。随机选取部分测序样本进行RSV序列对比分析,测序样本与参考毒株间的亲缘关系较近。2016-2018年B亚型的分离率明显高于A亚型。冬、春季分离率都很高,并以冬季为最。阳性样本的男女性别比为2.6∶1,男女性别比差异有统计学意义(χ^(2)=15.98,P<0.05)。感染患儿年龄分布在0~5岁之间,0~1岁组患儿RSV阳性样本最高,占57.34%,人群年龄分布差异有统计学意义(χ^(2)=7.22,P<0.05)。结论 RSV是2016-2018年儿童急性下呼吸道感染的主要原因,年龄主要分布在0~1岁;3年中以RSV A、B这2种亚型的共同流行,尤以B亚型为主。

Objective To isolate respiratory syncytial virus(RSV)and analyze epidemiological characteristics in children with acute lower respiratory tract infection in Gansu Provincial Maternity and Child-care Hospital from 2016 to 2018.Methods A total of 425 respiratory secretion samples were collected and blindly seeded in Vero cell line for 3 consecutive passages.The culture solutions were harvested and detected by RT-PCR,respectively.The positive samples were sequenced to determine the type in RSV and epidemic characteristics were investigated.Results A total of 143 samples were RSV positive among 425 samples,with a positive rate of 33.6%.The cell pathological efforts such as cell fusion were observed in partial Vero cells infected with RSV.The specific bands of RSV positive samples amplified by RT-PCR were consistent with the expected size of 180 bp,and subsequently sequence comparative analysis showed closed genetic relationship between sequencing of RSV positive samples and the reference strains.The separation rate of subtype B was significantly higher than that of subtype A from 2016 to 2018,with the highest in winter and spring.The case ratio for male to female was 2.6:1 in children with RSV positive,and the difference was statistically significant(χ^(2)=15.98,P<0.05).The age of infected children ranged from 0 to 5 years old,among which 57.34%of RSV children were under 1 year old.The difference of age distribution was statistically significant(χ^(2)=7.22,P<0.05).Conclusion RSV was the main cause of acute lower respiratory tract infection in infants and children from 2016 to 2018 in our hospital,and the age of infection was mainly distributed under the age of 1 year old.RSV subtype A and B were common prevalent,and the predominate epidemic strains of RSV attributed to subtype B.