Detection of porcine circovirus from lesions of a pig with wasting diseasein Japan

A wasting disease characterized by progressive weight loss and dyspnea has been observed in weaning pigs on a farm in Yamagata Prefecture in 1998. His topathologic findings in an affected pig were bronchointerstitial pneumonia and intracytoplasmic clusters of basophilic inclusions in macrophages of l ymph nodes, which were similar to those in pigs with postweaning multisyste mic wasting syndrome (PMWS) recently reported in North America and Europe. Porcine circovirus (PCV)-like particles were observed in bronchial lymph no de of the pig by electron microscopy, and PCV antigens were detected in the lesions by immunohistochemical staining. PCV DNA was also detected in the lung and tonsil by PCR, and restriction fragment length polymorphism analys is of the PCR products with HinfI showed the same type of the PCV associate d with PMWS (pmws PCV). Homology of nucleotide sequences between the PCR pr oduct and corresponding regions of published pmws PCV genomes was very high . These results indicated that virus detected in this study was pmws PCV. T o our knowledge, this is the first report on the presence of pmws PCV in Ja pan.