PDF(Pubmed)
Abstract：
Genomic characterization of circulating influenza type-A viruses (IAVs) directs the selection of appropriate vaccine formulations and early detection of potentially pandemic virus strains. However, longitudinal data on the genomic evolution and transmission of IAVs in Africa are scarce, limiting Africa\'s benefits from potential influenza control strategies. We searched seven databases: African Journals Online, Embase, Global Health, Google Scholar, PubMed, Scopus, and Web of Science according to the PRISMA guidelines for studies that sequenced and/or genomically characterized Africa IAVs. Our review highlights the emergence and diversification of IAVs in Africa since 1993. Circulating strains continuously acquired new amino acid substitutions at the major antigenic and potential N-linked glycosylation sites in their hemagglutinin proteins, which dramatically affected vaccine protectiveness. Africa IAVs phylogenetically mixed with global strains forming strong temporal and geographical evolution structures. Phylogeographic analyses confirmed that viral migration into Africa from abroad, especially South Asia, Europe, and North America, and extensive local viral mixing sustained the genomic diversity, antigenic drift, and persistence of IAVs in Africa. However, the role of reassortment and zoonosis remains unknown. Interestingly, we observed substitutions and clades and persistent viral lineages unique to Africa. Therefore, Africa\'s contribution to the global influenza ecology may be understated. Our results were geographically biased, with data from 63% (34/54) of African countries. Thus, there is a need to expand influenza surveillance across Africa and prioritize routine whole-genome sequencing and genomic analysis to detect new strains early for effective viral control.
摘要：
循环甲型流感病毒（IAV）的基因组表征指导选择合适的疫苗制剂和早期检测潜在的大流行性病毒株。然而,关于非洲IAV基因组进化和传播的纵向数据很少，限制非洲从潜在的流感控制策略中受益。我们搜索了七个数据库：非洲在线期刊，Embase,全球卫生,谷歌学者，PubMed,Scopus,和WebofScience根据PRISMA指南对非洲IAV进行测序和/或基因组表征的研究。我们的审查强调了自1993年以来非洲IAV的出现和多样化。循环菌株在血凝素蛋白的主要抗原和潜在的N-连接糖基化位点上不断获得新的氨基酸取代。这极大地影响了疫苗的保护性。非洲IAVs在系统发育上与全球菌株混合，形成了强大的时间和地理进化结构。系统地理分析证实，病毒从国外迁移到非洲，尤其是南亚,欧洲,北美,广泛的局部病毒混合维持了基因组多样性，抗原漂移，以及无人机在非洲的持续存在。然而,重组和人畜共患的作用仍然未知。有趣的是,我们观察到了非洲特有的替换和进化枝以及持续性病毒谱系.因此,非洲对全球流感生态的贡献可能被低估了。我们的结果在地理上有偏差，数据来自63%(34/54)的非洲国家。因此，有必要在非洲范围内扩大流感监测,并优先进行常规的全基因组测序和基因组分析,以便及早发现新毒株,从而有效控制病毒.
