Genetic characterization and molecular epidemiological analysis of novel enterovirus EV-B80 in China

Zhenzhi Han,Yong Zhang,Keqiang Huang,Hui Cui,Mei Hong,Haishu Tang,Yang Song,Qian Yang,Shuangli Zhu,Dongmei Yan,Wenbo Xu

doi:10.1038/s41426-018-0196-9

Abstract

Enterovirus B80 (EV-B80) is a newly identified serotype belonging to the enterovirus B species. To date, only two full-length genomic sequences of EV-B80 are available in GenBank, and few studies on EV-B80 have been conducted in China or worldwide. More information and research on EV-B80 is needed to assess its genetic characteristics, phylogenetic relationships, and association with enteroviral diseases. In this study, we report the phylogenetic characteristics of three Xinjiang EV-B80 strains and one Tibet EV-B80 strain in China. The full-length genomic sequences of four strains show 78.8–79% nucleotide identity and 94–94.2% amino acid identity with the prototype of EV-B80, indicating a tendency for evolution. Based on a maximum likelihood phylogenetic tree based on the entire VP1 region, three genotypes (A–C) were defined, revealing the possible origin of EV-B80 strains in the mainland of China. Recombination analysis revealed intraspecies recombinations in all four EV-B80 strains in nonstructural regions along with two recombination patterns. Due to the geographic factor, the coevolution of EV-B strains formed two different patterns of circulation. An antibody seroprevalence study against EV-B80 in two Xinjiang prefectures also showed that EV-B80 strains were widely prevalent in Xinjiang, China, compared to other studies on EV-B106 and EV-B89. All four EV-B80 strains are not temperature sensitive, showing a higher transmissibility in the population. In summary, this study reports the full-length genomic sequences of EV-B80 and provides valuable information on global EV-B80 molecular epidemiology.

Highlights

Introduction The genusEnterovirus (EV), belonging to the familyPicornaviridae, order Picornavirales, contains 15 species assigned to enterovirus A–L as well as rhinovirus A–C1
The EV Genotyping Tool results indicated that the query sequences showed 86% identity with known Enterovirus B80 (EV-B80) strains in GenBank and showed 73% identity with the EV-B80 prototype strain
The four strains clustered with the EV-B80 prototype with a bootstrap value higher than 95% (Fig S3a-b), so all four strains were identified as EV-B8021

Summary

Introduction

Introduction The genusEnterovirus (EV), belonging to the familyPicornaviridae, order Picornavirales, contains 15 species assigned to enterovirus A–L as well as rhinovirus A–C1. Enterovirus A–D (EV-A, EV-B, EV-C, and EV-D) are species that can infect humans and consist of more than 100 serotypes, including poliovirus, coxsackievirus, echovirus, and some newly discovered enteroviruses. Han et al Emerging Microbes & Infections (2018)7:193 molecular typing technologies and other methods in recent years[5,6,7]. The VP1 coding region of Enterovirus was used to identify the serotype because VP1 is the most external and immunodominant region containing the most important specific antigenic neutralization sites among the capsid proteins[8,9,10]. The molecular typing method based on VP1 coding region variation is used to confirm the serotypes and has gradually replaced the traditional neutralization test[8,11,12,13]

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Results

Conclusion