Activated Borna disease virus in affective disorders.

BACKGROUND: Borna disease virus (BDV) is an animal pathogen that causes behavioral changes in animals. Previous studies have found a high prevalence of serum antibodies as well as Borna disease viral antigens (BDVAGs) and RNA in the white blood cells of psychiatric patients, especially those with affective disorders. The present study attempts to offer a better description of the BDVAG cohort using clinical parameters. METHODS: The prevalence of BDVAG was examined in the peripheral mononuclear leukocytes of patients with a major depressive episode. A subgroup of patients underwent further clinical analysis. RESULTS: In this pilot study, at least, there was a significant difference in the prevalence of BDVAG between psychiatric inpatients with a major depressive episode and control individuals. It also appeared that BDVAG is more frequent in patients with recurrent major depression or bipolar disorder than in those with any other psychiatric disorder studied. The number of previous depressive episodes, as well as symptoms involving fatigue and concentration difficulties were positively related to BDVAG. CONCLUSIONS: The high rate of BDVAG, especially in fatigued patients with recurrent major depression or bipolar disorder, may be a nonspecific aspect of immunosuppression. The question remains whether this neurotropic virus may contribute to the pathogenesis of some types of affective disorder.