2013年贵州省急性弛缓性麻痹病例中非脊髓灰质炎肠道病毒的鉴定分析

Identification and genetic characteristics of non-polio enteroviruses isolated from acute flaccid paralysis cases in Guizhou Province of China,2013

目的研究2013年贵州省急性弛缓性麻痹(acute flaccid paralysis,AFP)病例中非脊髓灰质炎肠道病毒(nonpolio enterovirus,NPEV)的基因型别,并对分离的柯萨奇病毒A4型(coxsackievirus,CVA4)进行基因特征分析。方法 2013年贵州省共报告15岁以下AFP病例235例,采用RD细胞和L20B细胞对235例AFP病例粪便标本进行病毒分离,对分离到的NPEV进行VP1基因序列测定分型。通过MEGA7.0软件采用邻位相接法(neighbor joining method)构建遗传进化树进行基因特征分析,可靠性通过1 000bootstrap值评估。结果 235例AFP病例中共检测到24株NPEV(10.2%),有2株无法定型,另外22株共包括12个血清型,其中人类肠道病毒(human enterovirus,HEV)A组包括4个血清型6株,其中3株为CVA4,均属于C2基因亚型;HEV-B组包括7个血清型15株,1株为HEV-C组,未分离到HEV-D组病毒。结论 2013年贵州省AFP病例病原谱包括多种型别的NPEV,其中CVA4基因特征分析表明2013年贵州地区流行的CVA4毒株为C2基因亚型。

To study the genotype of non-polio enterovirus （NPEV） isolates from acute flaccid paralysis （AFP） cases in Guizhou Province of China in 2013 and to analyze the genetic characteristics of coxsackievirus A4 （CVA4） strains, a total of 235 cases under 15 years old with AFP were reported of Guizhou Province of China. Human rhabdomyosarcoma （RD） cells and L20B cells were used for virus isolation. The serotypes of isolated NPEV strains were identified by VP1 sequencing, phylogenetic tree was constructed by MEGA7.0 software for genetic characterization based on neighbor joining algorithm and the reliability of the phylogenetic trees was determined by bootstrap analysis with 1 000 pseudo replicate datasets. The results showed that 24 NPEV strains were isolates from 235 AFP cases, including 2 strains un-typed. Among the 22 strains, a total of 12 serotypes were identified, 6 strains belonged to human enterovires （HEV） A viruses including 4 serotypes, 3 strains was CVA 4 and belonged to the C2 subgenotype. A total of 15 strains belonged to HEV-B viruses including 7 serotypes and the other 1 strains belonged to HEV-C group. No NPEV strain of HEV-D group was detected. In 2013, the pathogen spectrum of AFP cases included several serotypes of HEV and the genetic characteristics showed that CVA4 strains of C2 subgenotype were the predominant genotype in Guizhou Province.