Magagula Nonkululeko B, Esona Mathew D, Nyaga Martin M, Stucker Karla M, Halpin Rebecca A, Stockwell Timothy B, Seheri Mapaseka L, Steele A Duncan, Wentworth David E, Mphahlele M Jeffrey
Medical Research Council/Diarrhoeal Pathogens Research Unit, Department of Virology, University of Limpopo, Medunsa Campus/National Health Laboratory Service, Pretoria, South Africa.
J Med Virol. 2015 Jan;87(1):79-101. doi: 10.1002/jmv.23971. Epub 2014 May 20.
Group A rotaviruses (RVAs) are the leading cause of severe gastroenteritis and eventually death among infants and young children worldwide, and disease prevention and management through vaccination is a public health priority. In August 2009, Rotarix™ was introduced in the South African Expanded Programme on Immunisation. As a result, substantial reductions in RVA disease burden have been reported among children younger than 5 years old. Rotavirus strain surveillance post-vaccination is crucial to, inter alia, monitor and study the evolution of vaccine escape strains. Here, full-genome sequence data for the 11 gene segments from 11 South African G1P[8] rotavirus strains were generated, including 5 strains collected from non-vaccinated children during the 2004-2009 rotavirus seasons and 6 strains collected from vaccinated children during the 2010 rotavirus season. These data were analyzed to gain insights into the overall genetic makeup and evolution of South African G1P[8] rotavirus strains and to compare their genetic backbones with those of common human Wa-like RVAs from other countries, as well as with the Rotarix™ and RotaTeq™ G1P[8] vaccine components. All 11 South African G1P[8] strains revealed a complete Wa-like genotype constellation of G1-P[8]-I1-R1-C1-M1-A1-N1-T1-E1-H1. On the basis of sequence similarities, the South African G1P[8] strains (with the exception of strain RVA/Human-wt/ZAF/1262/2004/G1P[8]) were closely related to each other (96-100% identity in all gene segments). Comparison to the Rotarix™ and RotaTeq™ G1P[8] vaccine components revealed a moderate nucleotide identity of 89-96% and 93-95%, respectively. The results indicated that none of the gene segments of these 11 South African G1P[8] strains were vaccine-derived. This study illustrates that large-scale next generation sequencing will provide crucial information on the influence of the vaccination program on evolution of rotavirus strains. This is the first report to describe full genomic analyses of G1P[8] RVA strains collected from both non-vaccinated and vaccinated children in South Africa.
A组轮状病毒（RVAs）是全球婴幼儿严重胃肠炎乃至死亡的主要原因，通过接种疫苗预防和管理该疾病是一项公共卫生重点工作。2009年8月，Rotarix™疫苗被纳入南非扩大免疫规划。结果显示，5岁以下儿童的轮状病毒疾病负担大幅降低。疫苗接种后轮状病毒株监测对于监测和研究疫苗逃逸株的演变等至关重要。在此，我们获得了来自11株南非G1P[8]轮状病毒株11个基因片段的全基因组序列数据，其中包括2004 - 2009年轮状病毒流行季从未接种疫苗儿童中收集的5株病毒，以及2010年轮状病毒流行季从接种疫苗儿童中收集的6株病毒。对这些数据进行分析，以深入了解南非G1P[8]轮状病毒株的整体基因组成和进化情况，并将其基因骨架与其他国家常见的人Wa样轮状病毒以及Rotarix™和RotaTeq™ G1P[8]疫苗成分的基因骨架进行比较。所有11株南非G1P[8]病毒株均呈现出完整的Wa样基因型组合G1 - P[8] - I1 - R1 - C1 - M1 - A1 - N1 - T1 - E1 - H1。基于序列相似性，南非G1P[8]病毒株（除RVA/Human - wt/ZAF/1262/2004/G1P[8]毒株外）彼此密切相关（所有基因片段的同一性为96 - 100%）。与Rotarix™和RotaTeq™ G1P[8]疫苗成分相比，核苷酸同一性分别为中等水平的89 - 96%和93 - 95%。结果表明，这11株南非G1P[8]病毒株的基因片段均非源自疫苗。本研究表明，大规模下一代测序将为疫苗接种计划对轮状病毒株进化的影响提供关键信息。这是首篇描述从南非未接种疫苗和接种疫苗儿童中收集的G1P[8]轮状病毒株全基因组分析的报告。
