IMPROVEMENT OF DIAGNOSTIC METHODS FOR INF ECTIOUS-DISEASES

Diagnostic methods to be used in case of notifiable infectious disease s have been regulated partly by regulations and partly fry guidelines to be considered obligatory. The use of internationally accepted stand ard methods is especially important because the veterinary authorities issue different transport papers, certificates based on the results o f these investigations. Only with a few exceptions, the diagnosis of i nfectious diseases in the list A of Office International des Epizootie s is the responsibility of central veterinary laboratories in each cou ntry. The laboratory procedures are based on the demonstration of viru s its antigen or nucleic acid in the animal tissues, isolation of viru s, as well as demonstration of antibodies developing in tile blood sa um by different methods. ELISA and virus isolation are used for the de monstration of foot-and-mouth disease (FMD) virus. Serum antibodies ar e demonstrated by virus neutralization or ELISA tests. In case of swin e vesicular disease (SVD) the samples are tested parallel also for the presence of FMD virus. The SVD virus can be isolated in cell cultures of porcine origin and can not be isolated in those of bovine origin. Serum antibodies are demonstrated by virus neutralization and ELISA te sts. Immunofluorescent investigation of tissue samples and virus isola tion methods are used for the diagnosis of classical swine fever (CSF) . Monoclonal antibodies are used to differentiate among CSF, BVD virus and Suvac vaccine virus strains. Different ELISA and virus neutraliza tion test are used for the demonstration of serum antibodies. In case of a suspected African Swine Fever case, haemadsorption and immunofluo rescent tests are used for the demonstration of the virus and also pig s are inoculated with the suspected material. ELISA is used for the se rological diagnosis of EBL. Cultivation of avian influenza viruses is carried out in embryonated eggs. The type of virus is determined by im muno-diffusion rest and the type of haemagglutinin and neuraminidase a nd occasionally - the virulence have also been determined. Haemaggluti nation inhibition test is used for the demonstration of serum antibodi es. Practically tile same methods are used for tile diagnosis of Newca stle disease.