An integrated model of infection risk in a health-care environment
An integrated model of infection risk in a health-care environment
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DOI：
10.1111/j.1539-6924.2006.00802.x
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发表时间：
2006-08-01
期刊：
影响因子：
3.8
通讯作者：
Gang Sun
中科院分区：
文献类型：
--
作者：
Nicas, Mark;Gang Sun
某些呼吸道感染可通过手与粘膜接触、吸入和/或直接呼吸道飞沫喷雾传播。在患有这种传染性感染的患者所居住的房间中，纺织品和非纺织品表面上存在的病原体以及空气中存在的病原体为主治卫生保健工作者（HCW）提供了暴露源;此外，当患者咳嗽时与患者密切接触允许液滴喷雾暴露。我们提出了一个相关的源-环境-受体途径的综合模型，并在离散时间马尔可夫链模型中将这些途径中的物理元素表示为“状态”。我们估计在不同的步骤中的途径，和它们的关系的概率，病原体在一个国家已经移动到另一个国家的特定的时间间隔结束的转移率。给定纺织品和非纺织品表面和室内空气中的初始病原体负载，我们使用该模型来估计HCW的粘膜和呼吸道的预期病原体剂量。反过来，使用非阈值感染剂量模型，我们与预期剂量的感染风险。该系统是用一个假设的，但似乎合理的情况下，涉及通过咳嗽发出的病毒病原体说明。我们还使用该模型表明，纺织品表面上的杀菌整理有可能通过手到粘膜暴露途径大幅降低感染风险。
Certain respiratory tract infections can be transmitted by hand-to-mucous-membrane contact, inhalation, and/or direct respiratory droplet spray. In a room occupied by a patient with such a transmissible infection, pathogens present on textile and nontextile surfaces, and pathogens present in the air, provide sources of exposure for an attending health-care worker (HCW); in addition, close contact with the patient when the latter coughs allows for droplet spray exposure. We present an integrated model of pertinent source-environment-receptor pathways, and represent physical elements in these pathways as "states" in a discrete-time Markov chain model. We estimate the rates of transfer at various steps in the pathways, and their relationship to the probability that a pathogen in one state has moved to another state by the end of a specified time interval. Given initial pathogen loads on textile and nontextile surfaces and in room air, we use the model to estimate the expected pathogen dose to a HCW's mucous membranes and respiratory tract. In turn, using a nonthreshold infectious dose model, we relate the expected dose to infection risk. The system is illustrated with a hypothetical but plausible scenario involving a viral pathogen emitted via coughing. We also use the model to show that a biocidal finish on textile surfaces has the potential to substantially reduce infection risk via the hand-to-mucous-membrane exposure pathway.