2019—2023年吉林省长春市儿童急性呼吸道感染住院病例中人偏肺病毒的基因型别和流行特征分析

Genotype and epidemiological characteristics of human metapneumovirus among hospitalized cases of acute respiratory infection in children in Changchun City,Jilin Province from 2019 to 2023

目的了解吉林省长春市儿童急性呼吸道感染(ARI)住院病例中人偏肺病毒(HMPV)的基因型别和流行特征。方法采集2019年6月至2023年6月长春市儿童医院ARI住院病例的咽拭子标本,收集病例的流行病学和临床信息。采用荧光定量RT-PCR方法鉴定HMPV阳性病例,并对阳性病例的病毒核酸进行G基因扩增及亲缘关系分析。结果共纳入儿童ARI住院病例3311例,年龄范围为0~17岁,年龄M(Q_(1),Q_(3))为2(1,3)岁;男性患儿1811例(54.70%)。共检出HMPV阳性病例167例,检出率为5.04%,其中<5岁病例占92.81%(155/167)。2019年HMPV检出率为6.37%(30/471),2020年降至最低(2.31%,10/432),2021、2022年有所回升,检出率分别为4.70%(60/1277)和4.56%(21/461),2023年HMPV检出率升高至6.87%(46/670),不同年份间的检出率差异具有统计学意义(P<0.05)。不同年份HMPV的流行高峰也存在差异,表现为单峰或双峰流行。共获得79条HMPV的G基因序列,A亚型和B亚型分别占48.10%和51.90%,其中A亚型均为A2c重复插入变异株,B亚型以B2基因型为主。HMPV在不同年份中可表现为A、B亚型的单独流行或共流行,存在亚型更替模式。结论2019—2023年不同年份间长春市ARI儿童住院病例中HMPV检出率差异较大,且存在HMPV的A、B基因亚型更替模式。

Objective To investigate the genotype and epidemiological characteristics of human metapneumovirus(HMPV)among hospitalized cases with acute respiratory infections(ARI)in children in Changchun City,Jilin Province,China.Methods From June 2019 to June 2023,throat swabs of ARI inpatients in Changchun Children′s Hospital were collected,and their epidemiological and clinical information were also collected.Quantitative reverse transcription-PCR was used to identify HMPV-positive cases,followed by the amplification of the G gene and genetic analysis in the HMPV-positive cases.Results A total of 3311 children hospitalized with ARI were included in this study.Their age ranged from 0 to 17 years old,and the M(Q_(1),Q_(3))of age was 2(1,3)years.About 1811(54.70%)cases were males.A total of 167 HMPV-positive cases were detected with a positive rate of 5.04%,of which 92.81%(155/167)were children under 5 years old.The positive rate of HMPV in 2019 was 6.37%(30/471),which dropped to the lowest in 2020(2.31%,10/432).The HMPV-positive rate was then rebounded in 2021(4.70%,60/1277)and 2022(4.56%,21/461),which increased to 6.87%(46/670)in 2023.The difference in HMPV-positive rate among each year was statistically significant(P<0.05).The prevalence peak of HMPV varied in different years,showing either a unimodal or bimodal distribution in one year.A total of 79 HMPV G gene sequences were obtained,of which subtype A and subtype B accounted for 48.10%and 51.90%,respectively.All of the subtype A sequences were clarified as A2c duplicated variants,and subtype B was mainly B2 genotype.Besides,subtypes A and B were prevalent alone or co-circulated in different years,and there was a subtype replacement pattern in HMPV.Conclusion The positive rate of HMPV in hospitalized ARI cases in children is significantly different from 2019 to 2023 in Changchun City.Notably,there are certain switch patterns of HMPV subtypes A and B in different years.