Stochastic effects on endemic infection levels of disseminating versus local contacts
Stochastic effects on endemic infection levels of disseminating versus local contacts
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DOI：
10.1016/s0025-5564(02)00124-4
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发表时间：
2002-11-01
影响因子：
4.3
通讯作者：
Jacquez, G
中科院分区：
文献类型：
--
作者：
Koopman, JS;Chick, SE;Jacquez, G
对于相同一致的确定性区室 (DC) 和随机区室 (SC) 模型，两种混合水平对地方性感染水平的影响是不同的。当人口众多、免疫力短暂且混合普遍存在时，DC 和 SC 模型都会给出相似的流行水平。但局部传播和/或短暂免疫会降低 SC 模型中的总体人群感染水平，但不会降低 DC 模型中的总体感染水平。与 SC 模型显示的消除本地传播相比，DC 模型也无法检测到消除传播传播的更大影响。模型行为中出现这些差异的原因是，很少遇到来自遥远地点的感染且感染水平随机较低的地区感染率降低，而感染水平随机较高的地区不会降低失去感染的速度。在极端情况下，这会产生局部随机消亡，并随后在 SC 模型（而非 DC 模型）中建立敏感性。这种现象应该作用于所有具有变化的地理或社会感染源的地方性感染。标准流行病学调查和充分成分原因模型都无法捕获这些影响，因为它们是在个体之间不存在差异的情况下发生的。 (C) 2002 Elsevier Science Inc. 保留所有权利。
The effects of two levels of mixing on endemic infection levels are shown to differ for identically conformed deterministic compartmental (DC) and stochastic compartmental (SC) models. Both DC and SC models give similar endemic levels when populations are large, immunity is short lived, and mixing is universal. But local transmissions and/or transient immunity decrease overall population infection levels in SC but not in DC models. DC models also fail to detect the greater effects of eliminating disseminating transmissions in comparison to eliminating local transmissions shown by SC models. These differences in model behavior arise because localities that encounter few infections from distant sites and that have stochastically low infection levels have decreased infection rates while localities with stochastically high levels of infection do not decrease the rate at which they lose infection. At the extreme this generates local stochastic die out with subsequent build up of susceptibility in SC but not DC models. This phenomenon should act upon all endemic infections that have changing geographic or social foci of infection. Neither standard epidemiological investigations nor sufficient-component cause models can capture these effects because they occur in the absence of differences between individuals. (C) 2002 Elsevier Science Inc. All rights reserved.