Repeated administration of maximum payload emergency vaccines made from inactivated purified antigen concentrates do not induce significant titres of antibodies against non-structural proteins of Foot-and-Mouth disease virus

Introduction At the present time, there is not an officially (Office International des Epizooties) prescribed procedure for the routine discrimination of animals which have been infected with foot and mouth disease virus (and have otherwise fully recovered) from those which have received vaccination only. The official serological methods measure only antibodies against the structural proteins of the virus and, under normal circumstances, where there is no supporting clinical picture or other evidence, are unable to differentiate between those antibodies induced by vaccine or previous exposure to live virus. All of this has significant implications for the export of livestock or livestock products from countries which are either free of FMD with vaccination or decide to use vaccine as a control measure for a recent introduction of the disease.