背景:C型流感病毒是导致儿童急性呼吸道疾病的病原体。由于与甲型或乙型流感病毒相比分离的病毒数量少,因此有关该病毒的临床信息有限。
方法:在2006年至2020年的15年间,通过在一家医院和一家诊所进行的细胞培养方法进行的临床试验,共分离出60种C型流感病毒。对这60例患者进行回顾性分析,比较门诊患者和住院患者。此外,在研究期间分析分离的病毒的基因组变化。
结果:所有人都小于7岁,73%的住院患者(26人中有19人)年龄在2岁以下。肺炎的发生频率有显著差异,占住院和门诊患者的45%和4%,分别。从2006年到2012年分离出的大多数病毒都属于C/圣保罗谱系的S/A亚谱系,但是三种亚谱系病毒,包括具有K190N突变的S/A亚谱系,S/V亚谱系,和C/神奈川血统,自2014年以来已共同发行。此外,自2014年以来,S/A亚谱系病毒正在进行重组,这表明该病毒发生了重大变化,抗原性和遗传学。在肺炎患者的10株菌株中,7个在S/A子谱系中,从2006年到2012年发行。
结论:2岁以下的婴儿更有可能因肺炎住院。2014年发生的基因组变化被认为会影响病毒的传播能力。
Influenza C virus is a pathogen that causes acute respiratory illness in children. The clinical information about this virus is limited because of the small number of isolated viruses compared to influenza A or B viruses.
A total of 60 influenza C viruses were isolated by clinical tests using cell culture methods conducted in one hospital and one clinic during the 15 years from 2006 to 2020. These 60 cases were retrospectively analyzed by comparing outpatients and inpatients. Moreover, isolated viruses were analyzed for genomic changes during the study period.
All were younger than 7 years, and 73% of inpatients (19 out of 26) were under 2 years of age. A significant difference was found in the frequency of pneumonia, accounting for 45% and 4% of inpatients and outpatients, respectively. Most of the viruses isolated from 2006 to 2012 belonged to the S/A sublineage of the C/Sao Paulo lineage, but three sublineage viruses, including the S/A sublineage with K190N mutation, S/V sublineage, and C/Kanagawa lineage, have cocirculated since 2014. Moreover, S/A sublineage viruses were undergoing reassortment since 2014, suggesting significant changes in the virus, both antigenically and genetically. Of the 10 strains from patients with pneumonia, 7 were in the S/A sublineage, which had circulated from 2006 to 2012.
Infants under 2 years of age were more likely to be hospitalized with pneumonia. The genomic changes that occurred in 2014 were suggested to affect the ability of the virus to spread.