Section of Epidemiology and Public Health, School of Veterinary Medicine, University of Pennsylvania, Kennett Square, PA, 19348, United States.
Department of Epidemiology and Biostatistics, Drexel University School of Public Health, Bellet Building, 6th Floor, 1505 Race Street, Philadelphia, PA, 19102, United States.
Epidemics. 2018 Jun;23:71-75. doi: 10.1016/j.epidem.2017.12.006. Epub 2017 Dec 14.
Contact tracing is a crucial component of the control of many infectious diseases, but is an arduous and time consuming process. Procedures that increase the efficiency of contact tracing increase the chance that effective controls can be implemented sooner and thus reduce the magnitude of the epidemic. We illustrate a procedure using Graph Theory in the context of infectious disease epidemics of farmed animals in which the epidemics are driven mainly by the shipment of animals between farms. Specifically, we created a directed graph of the recorded shipments of deer between deer farms in Pennsylvania over a timeframe and asked how the properties of the graph could be exploited to make contact tracing more efficient should Chronic Wasting Disease (a prion disease of deer) be discovered in one of the farms. We show that the presence of a large strongly connected component in the graph has a significant impact on the number of contacts that can arise.
接触者追踪是许多传染病控制的重要组成部分，但却是一个艰巨且耗时的过程。提高接触者追踪效率的程序可以增加实施有效控制的机会，从而减少疫情的规模。我们将使用图论来说明在主要由农场之间动物运输驱动的养殖动物传染病疫情的背景下的一种程序。具体来说，我们创建了一个宾夕法尼亚州鹿养殖场之间记录的鹿运输的有向图，并询问如果在其中一个农场发现慢性消耗病（一种鹿的朊病毒病），如何利用图的性质来提高接触者追踪的效率。我们表明，图中存在一个大的强连通分量对可能出现的接触者数量有重大影响。
