REVIEW A Review of Network Analysis Terminology and its Application to Foot-and-Mouth Disease Modelling and Policy Development C. Dube ´ 1,2 , C. Ribble 3 , D. Kelton 1 and B. McNab 4 1 Department of Population Medicine, Ontario Veterinary College, University of Guelph, Guelph, ON, Canada 2 Animal Health Division, Canadian Food Inspection Agency, Ottawa, ON, Canada 3 Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada 4 Office of the Chief Veterinarian for Ontario, Ontario Ministry of Agriculture, Food and Rural Affairs, ON, Canada Introduction One of the major problems facing policy makers in coun- tries free of highly contagious diseases such as foot-and- mouth disease (FMD) is the difficulty in assessing the potential consequences of an outbreak. Developing eradi- cation strategies in such situations can be difficult. This is especially true in a large country like Canada, which does not have recent experience with FMD (Sellers and Daggu- paty, 1990). Disease modelling as an input into policy formulation can be useful to assess the possible conse- quences of disease introductions and test control strate- gies on simulated outbreaks (Garner et al., 2007). Various models have been developed in FMD-free countries or regions such as Australia (Garner and Beckett, 2005), New Zealand (Sanson, 1993), the Netherlands (Tomassen et al., 2002; Velthuis and Mourits, 2007) and North America (Bates et al., 2003; Schoenbaum and Disney, 2003; Harvey et al., 2007). Models were also developed during the 2001 FMD outbreak in the United Kingdom (Ferguson et al., 2001a,b; Keeling et al., 2001) and reviews of these models have been published (Green and Medley, 2002; Kao, 2002; Taylor, 2003; Keeling, 2005). Quick detection of infected farms and subsequent implementa- tion of effective control measures will influence the suc- cess of an eradication strategy. By using computer models to study these scenarios in advance, it is hoped that deci- sion-making at first diagnosis of FMD will be improved (Taylor, 2003). The process of modelling diseases like FMD invariably involves defining a contact structure among animals and/or farms in a population, depending on the scale of Keywords: Foot-and-mouth disease; network analysis; animal movements Correspondence: C. Dube ´ . Terrestrial Animal Health Division, Canadian Food Inspection Agency, 59 Camelot, Ottawa, ON, Canada. Tel.: +450 424 0549; Fax: +613 228 6144; E-mail: Caroline.Dube@inspection.gc.ca Received for publication January 18, 2008 doi:10.1111/j.1865-1682.2008.01064.x Summary Livestock movements are important in spreading infectious diseases and many countries have developed regulations that require farmers to report livestock movements to authorities. This has led to the availability of large amounts of data for analysis and inclusion in computer simulation models developed to support policy formulation. Social network analysis has become increasingly popular to study and characterize the networks resulting from the movement of livestock from farm-to-farm and through other types of livestock operations. Network analysis is a powerful tool that allows one to study the relationships created among these operations, providing information on the role that they play in acquiring and spreading infectious diseases, information that is not readily available from more traditional livestock movement studies. Recent advances in the study of real-world complex networks are now being applied to veterinary epidemiology and infectious disease modelling and control. A review of the principles of network analysis and of the relevance of various complex network theories to infectious disease modelling and control is presented in this paper. Transboundary and Emerging Diseases ª 2009 Blackwell Verlag GmbH • Transboundary and Emerging Diseases. 56 (2009) 73–85 73