ABSTRACT. Anti-Borna disease virus (BDV) antibodies were detected from cats in Japan, Philippines and Indonesia by using electrochemiluminescence immunoassay. Positive rates were 3.1%, 3.8% and 2.0% in Japan, Philippines and Indonesia, respectively. There was no differences in the positive rate of anti-BDV antibodies between male and female cats and among habitats. While, a significantly (P<0.05) higher prevalence (6.5%) was found in the oldest age group (more than 6 years) cats. KEY WORDS: Borna disease virus (BDV), electrochemiluminescence immunoassay (ECLIA), feline.J. Vet. Med. Sci. 63(8): 921-923, 2001 Borna disease is an infectious neurological disease that occurs sporadically in horses and sheep in Central Europe. Borna disease virus (BDV) is a noncytolytic, neurotropic, single strand, negative sense RNA virus that naturally infects a wide range of vertebrate species from birds and rodents to primates [1,3]. BDV can also cause encephalomyelitis in a wide range of experimental animals [5,6,14].In domestic cats, an characteristic disease of the central nervous system has been observed in Sweden [9]; the dominating clinical sign is an unsteady (staggering) gait. Histopathological examination of the cats showed that the inflammatory reaction of the central nervous system was most pronounced in the grey matter of the brain stem, basal ganglia and hippocampus. These changes and laboratory findings including leukopenia and elevations in protein content and white blood cell count of the cerebrospinal fluid in affected cats suggested that staggering disease is infectious and most probably caused by virus. By using an indirect immunofluorescence assay (IFA), anti-BDV antibody has been detected in the cats with typical staggering disease [10,13]. Recently, the high prevalence of BDV infections has been demonstrated in domestic cats with neurological disorders in Japan [11].A seroepidemiological survey of the cat has been done by using IFA and/or Western blot (WB) analysis also in Japan [12]. Since the antibody titers were usually very low in Borna disease, an establishment of sensitive and reliable method to detect a small amount of anti-BDV antibodies is required. Recently, we have developed a new system, electrochemiluminescence immunoassay (ECLIA), using recombinant BDV p24 and p40 proteins, which has the sensitivity and specificity to serve as a serological screening method for measuring anti-BDV antibodies [16]. In this study we tried to detect anti-BDV antibodies of domestic cats in Asian countries and to compare the prevalence of BDV among the countries.Blood samples were collected from domestic cats at veterinary hospitals of University of Philippines Los Baños, Laguna, Philippines; Faculty of Veterinary Science, Bogor Agricultural University, Bogor, Indonesia; Osaka, Kitakyushu, Kumamoto and Nagasaki, Japan. Serum samples were stored at -30°C until use.To measure antibody against BDV, ECLIA is performed as previously described [16]. Briefly, micro beads were coated with horse-derived BDV p24 and p40 reco...