The detection of classical swine fever virus from autolysed organ and meatsamples

Classical swine fever (CSF) is a highly infectious disease of domestic pigs and wild boar. Detection of CSF virus (CSFV) is quite easy while using fre sh organ samples; difficulties arise when only autolytic biological materia l is available. This is of great importance with reference to wild boar, as these animals are suspected to be a reservoir of CSFV. The purpose of this study was to investigate the possibility of CSFV detection in relation to the post mortem period of infected pigs. Fourteen pigs, infected with a hig hly virulent strain W of CSFV, were used in this study. A wide range of org an (spleen, lymph nodes, tonsils, kidney) and meat samples were taken from dead or killed animals and then kept in a cold store at 8 degreesC. The sam ples were tested for CSFV by means of virus isolation, antigen ELISA and RT nested PCR after 1, 3, 7, 14 and 28 days of storage. Virus isolation seems to be the least sensitive method for detecting CSFV from this material. On ly spleen samples, taken from 3 animals and kept for a maximum of 14 days i n the cold store, were CSFV positive. Antigen ELISA gave much better result s, especially when spleen, lymph nodes and tonsils samples were taken, resu lting in positives up to 28 days. Meat samples tested by antigen ELISA gave inconclusive results. Therefore those samples were evaluated as unsuitable for CSFV detection. As expected, the best detection method was RT nested P CR, This resulted in the detection of CSFV up to 28 days from both organ an d meat samples from the cold store. In conclusion, the antigen ELISA seems to be only sensitive enough to detec t CSFV in organ samples. RT nested PCR should be the method of choice to te st autolysed organ and meat samples for CSFV.