Longdon Ben, Hadfield Jarrod D, Day Jonathan P, Smith Sophia C L, McGonigle John E, Cogni Rodrigo, Cao Chuan, Jiggins Francis M
Department of Genetics, University of Cambridge, Cambridge, United Kingdom.
Institute of Evolutionary Biology, University of Edinburgh, Edinburgh, United Kingdom.
PLoS Pathog. 2015 Mar 16;11(3):e1004728. doi: 10.1371/journal.ppat.1004728. eCollection 2015 Mar.
Emerging infectious diseases are often the result of a host shift, where the pathogen originates from a different host species. Virulence--the harm a pathogen does to its host-can be extremely high following a host shift (for example Ebola, HIV, and SARs), while other host shifts may go undetected as they cause few symptoms in the new host. Here we examine how virulence varies across host species by carrying out a large cross infection experiment using 48 species of Drosophilidae and an RNA virus. Host shifts resulted in dramatic variation in virulence, with benign infections in some species and rapid death in others. The change in virulence was highly predictable from the host phylogeny, with hosts clustering together in distinct clades displaying high or low virulence. High levels of virulence are associated with high viral loads, and this may determine the transmission rate of the virus.
新发传染病通常是宿主转移的结果，即病原体起源于不同的宿主物种。宿主转移后，病原体对宿主造成的危害——毒力可能极高（例如埃博拉病毒、艾滋病毒和非典），而其他宿主转移可能未被察觉，因为它们在新宿主中引起的症状很少。在这里，我们通过使用48种果蝇和一种RNA病毒进行大规模交叉感染实验，研究毒力如何在不同宿主物种间变化。宿主转移导致毒力发生显著变化，有些物种感染后症状轻微，而另一些则会迅速死亡。从宿主系统发育来看，毒力的变化具有高度可预测性，宿主在不同的进化枝中聚集在一起，显示出高毒力或低毒力。高毒力与高病毒载量相关，这可能决定了病毒的传播速度。
Zotero 插件
