Deltacoronavirus is the last identified Coronaviridae subfamily genus. Differing from other coronavirus (CoV) genera, which mainly infect birds or mammals, deltacoronaviruses (δ‐CoVs) reportedly infect both animal types. Recent studies show that a novel δ‐CoV, porcine deltacoronavirus (PDCoV), can also infect calves and chickens with the potential to infect humans, raising the possibility of cross‐species transmission of δ‐CoVs. Here, we explored the deep phylogenetic history and cross‐species transmission of δ‐CoVs. Virus–host cophylogenetic analyses showed that δ‐CoVs have undergone frequent host switches in birds, and sparrows may serve as the unappreciated hubs for avian to mammal transmission. Our molecular clock analyses show that PDCoV possibly originated in Southeast Asia in the 1990s and that the PDCoV cluster shares a common ancestor with Sparrow‐CoV of around 1,810. Our findings contribute valuable insights into the diversification, evolution, and interspecies transmission of δ‐CoVs and the origin of PDCoV, providing a model for exploring the relationships of δ‐CoVs in birds and mammals.

中文翻译：

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Deltacoronavirus 的跨物种传播和猪 Deltacoronavirus 的起源。

Deltacoronavirus 是最后发现的冠状病毒科亚科属。与主要感染鸟类或哺乳动物的其他冠状病毒 (CoV) 属不同，据报道，三角冠状病毒 (δ-CoV) 感染这两种动物类型。最近的研究表明，一种新型 δ-CoV 猪三角冠状病毒 (PDCoV) 也可以感染小牛和鸡，并有可能感染人类，从而增加了 δ-CoV 跨物种传播的可能性。在这里，我们探索了 δ-CoV 的深层系统发育历史和跨物种传播。病毒-宿​​主系统发育分析表明，δ-CoV 在鸟类中经历了频繁的宿主转换，而麻雀可能是禽类到哺乳动物传播的不为人知的枢纽。我们的分子钟分析表明，PDCoV 可能起源于 1990 年代的东南亚，并且 PDCoV 簇与 Sparrow-CoV 的共同祖先约为 1,810。