Kuiken Thijs, Holmes Edward C, McCauley John, Rimmelzwaan Guus F, Williams Catherine S, Grenfell Bryan T
Department of Virology, Erasmus Medical Center, 3015 GE Rotterdam, Netherlands.
Science. 2006 Apr 21;312(5772):394-7. doi: 10.1126/science.1122818.
Most emerging infectious diseases in humans originate from animal reservoirs; to contain and eradicate these diseases we need to understand how and why some pathogens become capable of crossing host species barriers. Influenza virus illustrates the interaction of factors that limit the transmission and subsequent establishment of an infection in a novel host species. Influenza species barriers can be categorized into virus-host interactions occurring within individuals and host-host interactions, either within or between species, that affect transmission between individuals. Viral evolution can help surmount species barriers, principally by affecting virus-host interactions; however, evolving the capability for sustained transmission in a new host species represents a major adaptive challenge because the number of mutations required is often large.
大多数人类新发传染病都源自动物宿主；为了控制和根除这些疾病，我们需要了解一些病原体是如何以及为何能够跨越宿主物种屏障的。流感病毒说明了限制在新宿主物种中传播及后续感染确立的各种因素之间的相互作用。流感的物种屏障可分为个体内发生的病毒-宿主相互作用以及影响个体间传播的物种内或物种间的宿主-宿主相互作用。病毒进化主要通过影响病毒-宿主相互作用来帮助跨越物种屏障；然而，要进化出在新宿主物种中持续传播的能力是一项重大的适应性挑战，因为所需的突变数量通常很多。
