Kiss Istvan Z, Green Darren M, Kao Rowland R
Department of Zoology, University of Oxford, Tinbergen Building, South Parks Road, Oxford OX1 3PS, UK.
Math Biosci. 2006 Sep;203(1):124-36. doi: 10.1016/j.mbs.2006.03.002. Epub 2006 Apr 19.
Heterogeneity in the number of potentially infectious contacts amongst members of a population increases the basic reproduction ratio (R(0)) and markedly alters disease dynamics compared to traditional mean-field models. Most models describing transmission on contact networks only account for one specific route of transmission. However, for many infectious diseases multiple routes of transmission exist. The model presented here captures transmission through a well defined network of contacts, complemented by mean-field type transmission amongst the nodes of the network that accounts for alternative routes of transmission. The impact of these combined transmission mechanisms on the final epidemic size is investigated analytically. The analytic predictions for the purely mean-field case and the transmission through the network-only case are confirmed by individual-based network simulations. There is a critical transmission potential above which an increased contribution of the mean-field type transmission increases the final epidemic size while an increased contribution of the transmission through the network decreases it. Below the critical transmission potential the opposite effect is observed.
与传统的平均场模型相比，人群中潜在感染性接触数量的异质性会增加基本繁殖数（R(0)），并显著改变疾病动态。大多数描述接触网络传播的模型仅考虑一种特定的传播途径。然而，对于许多传染病来说，存在多种传播途径。这里提出的模型通过一个定义明确的接触网络来捕捉传播，同时在网络节点之间补充了考虑替代传播途径的平均场类型传播。分析研究了这些组合传播机制对最终疫情规模的影响。通过基于个体的网络模拟证实了纯平均场情况和仅通过网络传播情况的分析预测。存在一个临界传播潜力，高于该潜力时，平均场类型传播的贡献增加会使最终疫情规模增加，而通过网络传播的贡献增加则会使其减小。在临界传播潜力以下，观察到相反的效果。
