标题： 过去流行病对未来疾病动态的影响 显示英文标题

标题： The Impact of Past Epidemics on Future Disease Dynamics

摘要： 许多病原体主要通过感染宿主和易感宿主之间的直接接触传播。 因此，人群的接触模式或接触网络从根本上决定了流行病的进程。 虽然关于网络中单一流行病的动力学有坚实的且不断发展的理论，但我们对网络结构对长期流行或地方性传播的影响了解甚少。 对于季节性传染病如流感，病原体会以复杂且不断变化的易感性和免疫力模式反复回到人群中，这些易感性和免疫力是通过先前感染获得的。 在这里，我们开发了两种数学方法，用于建模具有接触异质性的种群中部分免疫感染的连续季节性爆发。 使用渗透理论的方法，我们考虑了漏性免疫，即所有先前感染个体都获得部分免疫，以及完美免疫，即一部分先前感染个体完全免疫。 通过重新构建其宿主种群中流行病学活跃的部分，这类疾病限制了未来爆发的潜力。 我们推测，这些动态可能导致增加传染性的进化压力。 显示英文摘要

摘要： Many pathogens spread primarily via direct contact between infected and susceptible hosts. Thus, the patterns of contacts or contact network of a population fundamentally shapes the course of epidemics. While there is a robust and growing theory for the dynamics of single epidemics in networks, we know little about the impacts of network structure on long term epidemic or endemic transmission. For seasonal diseases like influenza, pathogens repeatedly return to populations with complex and changing patterns of susceptibility and immunity acquired through prior infection. Here, we develop two mathematical approaches for modeling consecutive seasonal outbreaks of a partially-immunizing infection in a population with contact heterogeneity. Using methods from percolation theory we consider both leaky immunity, where all previously infected individuals gain partial immunity, and perfect immunity, where a fraction of previously infected individuals are fully immune. By restructuring the epidemiologically active portion of their host population, such diseases limit the potential of future outbreaks. We speculate that these dynamics can result in evolutionary pressure to increase infectiousness.