Host heterogeneity in susceptibility and disease dynamics: Tests of a mathematical model
Host heterogeneity in susceptibility and disease dynamics: Tests of a mathematical model
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DOI：
10.1086/286089
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发表时间：
1997-12-01
影响因子：
2.9
通讯作者：
Buonaccorsi, JP
中科院分区：
文献类型：
--
作者：
Dwyer, G;Elkinton, JS;Buonaccorsi, JP
大多数疾病的数学模型都假设传播与宿主和病原体的密度呈线性关系。然而，最近的动物疾病数据对这一假设产生了怀疑，没有评估替代模型的有用性。在这篇文章中，我们使用的实验室剂量-反应实验，现场传输实验，观察自然发生的人口表明，舞毒蛾的病毒传播是一个非线性函数的病毒密度，显然是因为个体舞毒蛾幼虫在其对病毒的易感性的异质性。剂量反应实验表明，从实验室的舞毒蛾的殖民地的幼虫是基本上不均匀的病毒比从野生种群的幼虫的易感性，和现场实验表明，有一个更强烈的非线性关系传输和病毒密度野生幼虫比实验室幼虫。这种传播的非线性改变了病毒在自然种群中的动态，因此，与忽略宿主异质性的经典模型相比，将宿主对病毒的易感性异质性纳入模型中，可以更好地拟合来自大规模田间小区的病毒动态数据。我们的研究结果表明，个体之间的异质性在几个空间和时间尺度上的昆虫疾病的动态有重要影响，易感性的异质性可能是在疾病生态学的普遍重要性。
Most mathematical models of disease assume that transmission is linearly dependent on the densities of host and pathogen. Recent data for animal diseases, however, have cast doubt on this assumption, without assessing the usefulness of alternative models. In this article, we use a combination of laboratory dose-response experiments, field transmission experiments, and observations of naturally occurring populations to show that virus transmission in gypsy moths is a nonlinear function of virus density, apparently because of heterogeneity among individual gypsy moth larvae in their susceptibility to the virus. Dose-response experiments showed that larvae from a laboratory colony of gypsy moths are substantially less heterogeneous in their susceptibility to the virus than are larvae from feral populations, and field experiments showed that there is a more strongly nonlinear relationship between transmission and virus density for feral larvae than for lab larvae. This nonlinearity in transmission changes the dynamics of the virus in natural populations so that a model incorporating host heterogeneity in susceptibility to the virus gives a much better fit to data on virus dynamics from large-scale field plots than does a classical model that ignores host heterogeneity. Our results suggest that heterogeneity among individuals has important effects on the dynamics of disease in insects at several spatial and temporal scales and that heterogeneity in susceptibility may be of general importance in the ecology of disease.