Reconstruction of the Evolutionary History and Dispersal of Usutu Virus, a Neglected Emerging Arbovirus in Europe and Africa.
Reconstruction of the Evolutionary History and Dispersal of Usutu Virus, a Neglected Emerging Arbovirus in Europe and Africa.
复制标题
欧洲和非洲的新兴arbovirus忽视了USUTU病毒的进化史和扩散的重建。
DOI：
10.1128/mbio.01938-15
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发表时间：
2016-02-02
期刊：
影响因子：
6.4
通讯作者：
Schmidt-Chanasit J
中科院分区：
文献类型：
--
作者：
Engel D;Jöst H;Wink M;Börstler J;Bosch S;Garigliany MM;Jöst A;Czajka C;Lühken R;Ziegler U;Groschup MH;Pfeffer M;Becker N;Cadar D;Schmidt-Chanasit J
乌图病毒（USUV）是一种最被忽视的旧大陆脑炎黄病毒，在野生和圈养鸟类中引起动物流行病，并在人类中引起零星感染。USUV在其自然宿主中的传播和进化动力学尚不清楚。在这里，我们提出了所有可用的USUV菌株的遗传和进化历史，包括77个新测序的完整基因组从各种宿主物种在时间和空间尺度的分辨率。结果表明，USUV可以分为6个不同的谱系，最近的共同祖先的最近欧洲流行动物出现在非洲至少500年前。我们证明，USUV定期从非洲引入欧洲在过去的50年里，欧洲血统的遗传多样性主要是由原位进化，而非洲血统已被广泛的基因流驱动。大多数的氨基酸变化是有害的多态性纯化选择删除，适应性进化限制在NS 5基因和其他几个发展下情节定向选择，表明生态或免疫因素主要是USUV的传播和爆发的关键决定因素。已经检测到宿主特异性突变，而宿主转换分析确定蚊子是共同祖先的最可能来源，鸟类是最近欧洲USUV谱系的来源。我们的研究结果表明，主要的候鸟飞行路线可以预测的大陆和洲际传播模式的USUV和候鸟可能作为潜在的长距离传播媒介。流行性乙型脑炎病毒（USUV）是一种由蚊子传播的日本脑炎病毒抗原组黄病毒，主要在欧洲引起大规模鸟类死亡。越来越多的证据表明，USUV似乎对人类具有致病性，成为一个潜在的公共卫生问题。USUV在欧洲的出现使我们能够了解虫媒病毒如何在原始环境中传播，适应和进化。因此，了解有助于病毒性疾病出现、维持和进一步传播的流行病学和进化过程是制定和实施控制病毒性疾病的监测战略的必要条件。在这项工作中，我们使用所有已发表的序列和本研究期间生成的序列对USUV进行了广泛的地理和进化分析。随后，我们描述了遗传特征，重建了已确定病毒谱系的大陆/国家之间的潜在地理传播模式和病毒迁移的驱动因素，并追踪了不同宿主之间爆发和过渡事件的起源。
Usutu virus (USUV), one of the most neglected Old World encephalitic flaviviruses, causes epizootics among wild and captive birds and sporadic infection in humans. The dynamics of USUV spread and evolution in its natural hosts are unknown. Here, we present the phylogeny and evolutionary history of all available USUV strains, including 77 newly sequenced complete genomes from a variety of host species at a temporal and spatial scaled resolution. The results showed that USUV can be classified into six distinct lineages and that the most recent common ancestor of the recent European epizootics emerged in Africa at least 500 years ago. We demonstrated that USUV was introduced regularly from Africa into Europe in the last 50 years, and the genetic diversity of European lineages is shaped primarily by in situ evolution, while the African lineages have been driven by extensive gene flow. Most of the amino acid changes are deleterious polymorphisms removed by purifying selection, with adaptive evolution restricted to the NS5 gene and several others evolving under episodic directional selection, indicating that the ecological or immunological factors were mostly the key determinants of USUV dispersal and outbreaks. Host-specific mutations have been detected, while the host transition analysis identified mosquitoes as the most likely origin of the common ancestor and birds as the source of the recent European USUV lineages. Our results suggest that the major migratory bird flyways could predict the continental and intercontinental dispersal patterns of USUV and that migratory birds might act as potential long-distance dispersal vehicles. Usutu virus (USUV), a mosquito-borne flavivirus of the Japanese encephalitis virus antigenic group, caused massive bird die-offs, mostly in Europe. There is increasing evidence that USUV appears to be pathogenic for humans, becoming a potential public health problem. The emergence of USUV in Europe allows us to understand how an arbovirus spreads, adapts, and evolves in a naive environment. Thus, understanding the epidemiological and evolutionary processes that contribute to the emergence, maintenance, and further spread of viral diseases is the sine qua non to develop and implement surveillance strategies for their control. In this work, we performed an expansive phylogeographic and evolutionary analysis of USUV using all published sequences and those generated during this study. Subsequently, we described the genetic traits, reconstructed the potential pattern of geographic spread between continents/countries of the identified viral lineages and the drivers of viral migration, and traced the origin of outbreaks and transition events between different hosts.