PDF(Pubmed)
Abstract：
Coexistence of multiple strains of a pathogen in a host population can present significant challenges to vaccine development or treatment efficacy. Here we discuss a novel mechanism that can increase rates of long-lived strain polymorphism, rooted in the presence of social structure in a host population. We show that social preference of interaction, in conjunction with differences in immunity between host subgroups, can exert varying selection pressure on pathogen strains, creating a balancing mechanism that supports stable viral coexistence, independent of other known mechanisms. We use population genetic models to study rates of pathogen heterozygosity as a function of population size, host population composition, mutant strain fitness differences and host social preferences of interaction. We also show that even small periodic epochs of host population stratification can lead to elevated strain coexistence. These results are robust to varying social preferences of interaction, overall differences in strain fitnesses, and spatial heterogeneity in host population composition. Our results highlight the role of host population social stratification in increasing rates of pathogen strain diversity, with effects that should be considered when designing policies or treatments with a long-term view of curbing pathogen evolution.
摘要：
宿主群体中多种病原体菌株的共存可能对疫苗开发或治疗功效提出重大挑战。在这里，我们讨论了一种新机制，可以提高长寿命菌株多态性的比率，植根于宿主人口中社会结构的存在。我们证明了互动的社会偏好，结合宿主亚群之间的免疫力差异，可以对病原体菌株施加不同的选择压力，创建支持稳定病毒共存的平衡机制，独立于其他已知机制。我们使用群体遗传模型来研究病原体杂合率作为群体大小的函数，宿主种群组成，突变株适应度差异与宿主社会偏好的相互作用。我们还表明，即使宿主种群分层的小周期周期也会导致菌株共存。这些结果对不同的社会互动偏好是稳健的，应变率的总体差异，和寄主种群组成的空间异质性。我们的结果强调了宿主群体社会分层在增加病原体菌株多样性中的作用，具有在设计具有遏制病原体进化的长期观点的政策或治疗时应该考虑的效果。
