Genetic analysis of the VP1 region of enterovirus 71 reveals the emergence of genotype A in central China in 2008

Abstract

Enterovirus 71 (EV71) strains from children were characterized by full-length VP1 nucleotide sequencing. Out of 22 clinical specimens, five isolates identified as EV71 were recovered by virus isolation. The VP1 sequences of the five isolates had more than 97.4% sequence identity with prototype virus BrCr, clustering in the genotype A lineage. This represents the first record of genotype A EV71 in China since the BrCr prototype strain was discovered in the USA in 1969.

The role of enterovirus 71 and coxsackievirus A strains in a large outbreak of hand, foot, and mouth disease in 2012 in Changsha, China

“…In China, from 1998 to 2004, EV-71 belonged to cluster C4b, but after 2004, cluster C4a replaced C4b and became the predominant circulating strain. 12,36 As seen in Figure 2, all Changsha EV-71 strains reported here were clustered within the C4a clade, implying that C4a was also the most prominent EV-71 subgenotype in Changsha. The sequence homology was conserved in mild/severe and child/adult cases.…”

Virology, epidemiology, pathogenesis, and control of enterovirus 71

“…Group A consists of one member, the prototype BrCr strain, which was fi rst identifi ed in California, USA, in 1970, and was not reported outside the USA until 2008, when isolates were reported from fi ve of 22 children presenting with HFMD in Anhui province of central China. 67 Sequencing of the complete VP1 gene showed very little divergence between isolates. The virus might, therefore, have been circulating undetected in central China, with very little evolutionary change for 40 years, although the source of the virus templates that were sequenced could have aff ected the results.…”

Annexin II Binds to Capsid Protein VP1 of Enterovirus 71 and Enhances Viral Infectivity

“…In the past decade, the frequency of EV71 outbreaks associated with severe neurological illness appeared to have increased in the Pacific region, most notably in China, where large outbreaks have been occurring annually since 2007 (24, 53). While the epidemiological or virological mechanism underlying this regional focus of severe EV71 infection remains largely unknown, the impact of EV71 infection is a global concern, as evidenced by the increase in virological surveillance and studies of EV71 infection in many regions of the world (29,46,53).EV71 is composed of a single-stranded, positive-polarity RNA molecule surrounded by a nonenveloped, pentameric icosahedral capsid (3, 35), which consists of 60 copies of the four structural proteins VP1 to VP4. While there is no animal model for EV71 infection in humans, intraperitoneal injection of EV71 is lethal to suckling mice.…”

“…HFMD is largely a common self-limited childhood illness but may have complications of severe to fatal neurological symptoms in some children (1,5,6,16,21). In the past decade, the frequency of EV71 outbreaks associated with severe neurological illness appeared to have increased in the Pacific region, most notably in China, where large outbreaks have been occurring annually since 2007 (24,53). While the epidemiological or virological mechanism underlying this regional focus of severe EV71 infection remains largely unknown, the impact of EV71 infection is a global concern, as evidenced by the increase in virological surveillance and studies of EV71 infection in many regions of the world (29,46,53).…”