BORNA-DISEASE VIRUS-INFECTION IN ANIMALS AND HUMANS

The geographic distribution and host range of Borna disease (BE), a fa tal neurologic disease of horses and sheep, are larger than previously thought. The etiologic agent, Borna disease virus (BDV), has been ide ntified as an enveloped nonsegmented negative-strand RNA virus with un ique properties of replication. Data indicate a high degree of genetic stability of BDV in its natural host, the horse. Studies in the Lewis rat have shown that BDV replication does not directly influence vital functions; rather, the disease is caused by a virus-induced T-cell-me diated immune reaction. Because antibodies reactive with BDV have been found in the sera of patients with neuropsychiatric disorders, this r eview examines the possible link between BDV and such disorders. Seroe pidemiologic and cerebrospinal fluid investigations of psychiatric pat ients suggest a causal role of BDV infection in human psychiatric diso rders. In diagnostically unselected psychiatric patients, the distribu tion of psychiatric disorders was found to be similar in BDV seroposit ive and seronegative patients. In addition, BDV-seropositive neurologi c patients became ill with lymphocytic meningoencephalitis. In contras t to others, we found no evidence is reported for BDV RNA, BDV antigen s, or infectious BDV in peripheral blood cells of psychiatric patients .