Data from: Opportunities and challenges of Integral Projection Models for modeling host-parasite dynamics

Epidemiological dynamics are shaped by and may in turn shape host demography. These feedbacks can result in hard to predict patterns of disease incidence. Mathematical models that integrate infection and demography are consequently a key tool for informing expectations for disease burden and identifying effective measures for control. A major challenge is capturing the details of infection within individuals and quantifying their downstream impacts to understand population-scale outcomes. For example, parasite loads and antibody titres may vary over the course of an infection and contribute to differences in transmission at the scale of the population. To date, to capture these subtleties, models have mostly relied on complex mechanistic frameworks, discrete categorization and/or agent-based approaches. Integral Projection Models (IPMs) allow variance in individual trajectories of quantitative traits and their population-level outcomes to be captured in ways that directly reflect statistical models of trait–fate relationships. Given increasing data availability, and advances in modelling, there is considerable potential for extending this framework to traits of relevance for infectious disease dynamics. Here, we provide an overview of host and parasite natural history contexts where IPMs could strengthen inference of population dynamics, with examples of host species ranging from mice to sheep to humans, and parasites ranging from viruses to worms. We discuss models of both parasite and host traits, provide two case studies and conclude by reviewing potential for both ecological and evolutionary research.

流行病学动态既受宿主种群动态的塑造，又可反过来作用于宿主种群动态。这类反馈机制可催生难以预测的疾病发生模式。因此，整合感染与种群动态的数学模型，是预判疾病负担、制定有效防控措施的核心工具。当前一大挑战在于刻画个体层面的感染细节，并量化其下游效应，以解析种群尺度的疾病转归。例如，在感染进程中，寄生虫载量与抗体滴度可能发生动态变化，进而影响种群尺度下的传播差异。迄今为止，为刻画这类细微特征，相关模型多依赖复杂的机制性框架、离散分类手段，或基于智能体的建模方法。积分投影模型（Integral Projection Models，IPMs）能够以直接反映性状-结局关系统计模型的方式，量化定量性状的个体轨迹及其种群水平结局的变异。随着数据可得性的提升与建模技术的进步，将该框架拓展至与传染病动态相关的性状研究，具备巨大应用潜力。本文综述了宿主与寄生虫的自然史背景场景，在此类场景中积分投影模型可强化种群动态的统计推断，并列举了从小鼠、绵羊到人类的宿主物种，以及从病毒到蠕虫的寄生虫类群作为示例。本文将探讨寄生虫与宿主的性状模型，提供两个案例研究，并最终回顾该框架在生态学与进化生物学研究中的应用前景。