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Appendix 13 Global Update of Foot-and-Mouth Disease (2004-2006) Donald P King*, Nick J. Knowles, Jemma Wadsworth, Kate G. Swabey, Robert J. Statham, Yanmin Li, Geoff H. Hutchings, Scott M. Reid, Katja Ebert, Julie M. Stirling, Nigel P. Ferris and David J. Paton Institute for Animal Health, Ash Road, Pirbright, Surrey, GU24 0NF, United Kingdom. Abstract: This report summarizes the activities ofthe FAO World Reference Laboratory for Foot-and-Mouth Disease (WRLFMD) during the period from October 2004 to September 2006. During these 24 months, 998 clinical samples were received in the WRLFMD from 35 countries in Africa, Asia and Europe. This material was submitted for primary and referral diagnosis (to confirm the presence of FMD virus) and to perform antigenic characterisation andepidemiological monitoring of circulating virus strains in the world. The presence of FMD virus was determined using a combination of virus isolation (VI), antigen-ELISA and real-time RT-PCR. The genetic and antigenic relationships of FMD virus isolates were further defined using VP1 sequencing and serological comparisons to vaccine strains (r1-values). A summary of the results generated and furtherquarterly updates from the WRLFMD can be obtained from: http://www.iah.bbsrc.ac.uk/virus/. Performance data generated to support the use of real-time RT-PCR for diagnosis continue to be encouraging with FMD virus genome detected in 62.3% of the total samples compared with a 55.4% detection rate for virus by the combined use of VI and Ag-ELISA. Characterization of isolates recovered from the samplessubmitted showed that 6/7 FMD virus serotypes were represented, although type-O was the most frequently characterised serotype. Phylogenetic analysis of isolates was performed to provide further characterization data and to support epidemiological investigation into the source of outbreaks. Matching of selected field isolates against reference vaccine strains was performed to assess the likelycross-protection that might be afforded: in this respect, serotype A isolates continue to be the most problematic for antigenic matching. More details of the recent outbreaks of serotype Asia 1 in Asia, outbreaks of serotype A in Egypt in 2006 and the emergence of a further strain of serotype A in the Middle East and European Turkey are reported in other presentations at this meeting (Knowles et al.,2006 and Wadsworth et al., 2006). Although there have been no recent FMD incursions into officially FMD-free countries that do not practice vaccination, FMD continues to threaten the livestock industries of Europe and elsewhere. Introduction: Foot-and-mouth disease (FMD) is a highly contagious disease caused by a non-enveloped virus (FMDV). The virus exists as seven immunologically distinct serotypes(O, A, C, Asia 1, SAT 1, SAT 2 and SAT 3) that do not induce protection against each other after infection. In addition, within serotypes further antigenic variants can be identified that may induce incomplete cross protection against each other. FMD is endemic in large areas of Africa, Asia and South America and can readily cross international boundaries and cause epidemics in previously freeareas. The distribution of different FMD serotypes and subtypes varies according to countries and continents. Furthermore in some areas, several serotypes and subtypes can occur at the same time. However the pattern of serotypes and subtypes around the world is not static and is influenced by the type of disease control practised. This highly contagious virus is mainly transmitted by direct contactbetween naïve and infected animals or their products but it can also be spread by the airborne route or on fomites. In addition, the control of this disease is constantly challenged by the emergence of new strains. In order to develop and implement appropriate and effective control measures such as vaccines, sensitive diagnostics and contingency plans, it is important to determine the origin and...