Biomathematics and Bioinformatics Division, Rothamsted Research, Harpenden, AL5 2JQ, UK.
Phytopathology. 2010 Jul;100(7):638-44. doi: 10.1094/PHYTO-100-7-0638.
A number of high profile eradication attempts on plant pathogens have recently been attempted in response to the increasing number of introductions of economically significant nonnative pathogen species. Eradication programs involve the removal of a large proportion of a host population and can thus lead to significant social and economic costs. In this paper we use a spatially explicit stochastic model to simulate an invading pathogen and show that it is possible to identify an optimal control radius, i.e., one that minimizes the total number of hosts removed during an eradication campaign that is effective in eradicating the pathogen. However, by simulating the epidemic and eradication processes in multiple landscapes, we demonstrate that the optimal radius depends critically on landscape pattern (i.e., the spatial configuration of hosts within the landscape). In particular, we find that the optimal radius, and also the number of host removals associated with it, increases with both the level of aggregation and the density of hosts in the landscape. The result is of practical significance and demonstrates that the location of an invading epidemic should be a key consideration in the design of future eradication strategies.
最近，针对经济意义重大的非本地病原物种不断传入的情况，人们尝试了许多针对植物病原体的高知名度根除计划。根除计划涉及到宿主种群的大量移除，因此可能会导致重大的社会和经济成本。在本文中，我们使用空间显式随机模型来模拟入侵病原体，并表明可以确定一个最佳的控制半径，即能够在根除运动中最小化移除的宿主总数的半径，同时该运动可以有效地根除病原体。然而，通过在多个景观中模拟流行病和根除过程，我们证明最佳半径严重依赖于景观格局（即景观内宿主的空间配置）。具体来说，我们发现最佳半径，以及与之相关的宿主移除数量，随着景观中宿主的聚集程度和密度的增加而增加。该结果具有实际意义，表明入侵流行病的位置应该是未来根除策略设计的关键考虑因素。
