The host is refers to under the natural condition by the pathogen parasitism person or the animal.

宿主是指在自然条件下被病原体寄生的人或动物。

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Conclusion The natural foci of HFRS were extensively present in Guangxi with R. novegicus being the major host animal. SEOV was prevalent in the region.

结论 广西区广泛存在以褐家鼠为主要宿主的HFRS家鼠型疫源地，并存在汉城型汉坦病毒的流行。

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Until researchers can determine what animal is the natural host of the virus, and how MERS spreads from the host to humans, each new outbreak is dangerous and mysterious.

CNN: Why MERS virus is so scary

But no one knows which disease will be next, what animal will be its natural host, where it will happen, or how dangerous it will be.

ECONOMIST: Bird flu and public health