Isolation and Characterization of a Highly Mutated Chinese Isolate of Enterovirus B84 from a Patient with Acute Flaccid Paralysis.

Huanying Zheng,Wenbo Xu,Hui Li,Xue Guo,Ling Fang,Leng Liu,Changwen Ke,Jing Lu,Yong Zhang,Hanri Zeng

doi:10.1038/srep31059

Abstract

Enterovirus B84 (EV-B84) is a newly identified serotype within the species Enterovirus B (EV-B). To date, only ten nucleotide sequences of EV-B84 are published and only one full-length genome sequence (the prototype strain) is available in the GenBank database. Here, a highly mutated EV-B84 (strain AFP452/GD/CHN/2004) was recovered from a patient with acute flaccid paralysis in the Guangdong province of China in 2004 making this the first report of EV-B84 in China. Sequence comparison and phylogenetic dendrogram analysis revealed high variation from the global EV-B84 strains (African and Indian strains) and frequent intertypic recombination in the non-structural protein region, suggesting high genetic diversity in EV-B84. The Chinese EV-B84 strain, apparently evolving independently of the other ten strains, strongly suggests that the EV-B84 strain has been circulating for many years. However, the extremely low isolation rate suggests that it is not a prevalent EV serotype in China or worldwide. This study provides valuable information about the molecular epidemiology of EV-B84 in China, and will be helpful in future studies to understand the association of EV-B84 with neurological disorders; it also helps expand the number of whole virus genome sequences of EV-B84 in the GenBank database.

Highlights

Among the enterovirus serotypes, more than 60 are known human pathogens, even though most human enteroviral infections are asymptomatic or only result in mild disease, such as common cold
Molecular serotyping and primary characterization. Both RD (Human rhabdomyosarcoma) cells and HEp-2 (Human laryngeal carcinoma) cells support the growth of strain AFP452/GD/CHN/2004, and the appearance of cytopathic effects (CPEs) on RD cells is more rapid than on HEp-2 cells
Molecular serotyping of strain AFP452 based on the entire VP1 sequence was performed using an online EV genotyping tool[20], and the results indicated that strain AFP452 belongs to the Enterovirus B84 (EV-B84) serotype

Summary

Introduction

More than 60 are known human pathogens, even though most human enteroviral infections are asymptomatic or only result in mild disease, such as common cold. In some cases, enteroviruses are the most common viral cause of serious illnesses such as acute flaccid paralysis (AFP), acute myocarditis, aseptic meningitis, and neonatal sepsis-like disease[18]. We report the complete genome sequence of an EV-B84 isolate that was recovered from a child aged 5 years with AFP in the Guangdong province of China in 2004. The virus was identified by comparison with enterovirus prototype strains and the recent enterovirus isolates that were partially characterized. The data presented here indicates that a highly mutated EV-B84 strain is circulating in China, making this the first report of EV-B84 and its probable association with acute flaccid paralysis

Methods

Results

Conclusion