Evolution of virulence in a host-pathogen system with local pathogen transmission
Evolution of virulence in a host-pathogen system with local pathogen transmission
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DOI：
10.2307/3545985
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发表时间：
1995-12-01
期刊：
影响因子：
3.4
通讯作者：
deRoos, AM
中科院分区：
文献类型：
--
作者：
Claessen, D;deRoos, AM
如果宿主可以被多种病原体有效感染，并且病原体传播在空间上是同质的，那么自然选择有利于更高的毒力水平，因为病原体面临着与其他共同利用者共享宿主或完全输给更强大的竞争对手的风险。在病原体传播局限于相邻宿主之间的宿主-病原体系统中，受感染的宿主要么出现在相对较小的斑块中，被易感宿主彼此隔离，要么整个空间域或多或少均匀地被受感染的宿主覆盖，中间只有少数易感宿主。当多种病原体感染对病原体生产力产生很大的负面影响并导致毒性较低的病原体受到青睐时，就会出现斑片分布。当多重感染的危害性较小并导致毒性更强的病原体受到青睐时，受感染宿主就会出现连续分布。相反，当多重宿主感染不可能时，选择有利于具有最大基本繁殖率的病原体，而不管病原体传播的方式如何。由于局部病原体传播而出现的空间异质分布对病原体入侵和种群动态产生额外的影响。
If hosts can be effectively infected by more than a single pathogen and pathogen transmission is spatially homogeneous, natural selection favors higher virulence levels, since pathogens run the risk to share their host with other co-exploiters or lose it entirely to a stronger competitor. In a host-pathogen system where pathogen transmission is localized between neighboring hosts, infected hosts either occur in relatively small patches, isolated from each other by susceptible hosts, or the entire spatial domain is more or less evenly covered with infected hosts with only few susceptible hosts in between. The patchy distribution arises when multiple pathogen infections have a large negative effect on pathogen productivity and leads to less virulent pathogens being favored. The contiguous distribution of infected hosts occurs when multiple infections are less deleterious and leads to more virulent pathogens being favored. In contrast, when multiple host infections are not possible, selection favors the pathogen with a maximal basic reproduction ratio irrespective of the mode of pathogen transmission. The spatially heterogeneous distributions that emerge because of local pathogen transmission have additional consequences for pathogen invasion and population dynamics.