Detection of antibodies against Borna disease virus in sera and cerebrospinal fluid of horses in the USA

Abstract

Sera from 295 horses in the USA were examined by an indirect immunofluorescence assay and Western blot assays to determine the prevalence of Borna disease virus infection. Eight (2.7 per cent) of the samples were positive in both assays, and 18 (6.1 per cent) were positive only in the Western blot assay. The indirect fluorescence titres ranged from 1:20 to 1:80 of antibodies recognising the virus-specific antigen from Borna disease virus-infected cells. The purified virus-specific proteins isolated from infected rat brains were recognised by positive equine serum samples after immunostaining by a Western blot technique. Information obtained from the owners about the history of the seropositive horses revealed that they were either clinically normal or had a pathological diagnosis of disease unrelated to Borna disease. This is the first report of the detection of antibodies to Borna disease virus in horses in the USA. The disease may be more widespread in a subclinical form, with very long incubation periods, and may not necessarily be restricted to historically endemic areas.

Detection of Anti-Borna Disease Virus Antibodies from Cats in Asian Countries, Japan, Philippines and Indonesia Using Electrochemiluminescence Immunoassay.

“…Sporadic outbreaks of Borna disease have been reported in Germany [8]. There are several serological surveys from horses without giving rise to clinical signs in the Netherlands, and other European countries [8], the USA [7], Iran [2] and Japan [15], suggesting that the virus is more widely distributed than previously thought. In this paper, although we could not find any positive relationship between the detection of anti-BDV antibodies and the diseases such as neurological disorders in cats, we added Philippines and Indonesia as BDV-distributed countries.…”

Clinical, Serologic, and Histopathologic Characterization of Experimental Borna Disease in Ponies

“…These factors may underlie some of the difficulties in interpreting discordant BDV serologic test results. 3,8,10,13,14 Because BDV isolation is notoriously difficult, well-controlled RT-PCR procedures may be useful in detecting the presence of BDV nucleic acid in postmortem brain samples, as was true in this study.…”

“…This observation is pertinent because several recent studies have reported serologic evidence of BDV exposure in animal and human populations not previously known to harbor BDV. 1,10,13 Possible antigenic mimicry, absence of antibody in clinically ill animals, appearance of different antigen-specific antibodies at different times postinfection, and the presence of antibodies in clinically normal convalescent animals all complicate seroepidemiologic studies of BDV exposure in animal populations. In response to these concerns, some investigators have used stringent criteria for diagnosing seropositivity, requiring the recognition of Ն2 BDV proteins by immunoblot or immunoprecipitation prior to a seropositive classification.…”

Antemortem diagnosis of Borna disease (BD) in equids

“…Aus diesem Grund sind diese Methoden zur intra vitam Diagnose nicht zuverlässig. Somit sind positive Antikörperbefunde in der CSF mittels Westernblot bei stets negativen Ergebnissen im IFA bei inapparent infizierten Pferden (Kao et al, 1993) im vorgenannten Sinne zu interpretieren. Angaben zum Nachweis BDV-spezifischer Antikörper in Serum und Liquor bei an BD erkrankten Equiden mittels ELISA bzw.…”