A known virus in animals is suspected in humans. Borna disease virus has been detected in human neuropathy

Borna disease virus (BDV) is a newly classified non-segmented neurotrophic negative-strand RNA virus with a worldwide distribution and affecting warm-blooded animals ranging from birds to primates. Infection may be asymptomatic or results in manifest disturbances of movement behaviour. Although BDV has not been unequivocally implicated in any human disease, several reports have suggested relationship to exist between BDV infection and certain neuropsychiatric syndromes including affective disorders, chronic fatigue syndrome, and schizophrenia. Moreover, at least one centre has initiated a trial of antiviral therapy in patients with affective disorders attributable to BDV. The article consists in a review of recent advances in the molecular biology, pathogenesis and epidemiology of BDV, and an outline of anticipated directions for future research.