Health care professionals at risk of infection with Borna disease virus – evidence from a large hospital in China (Chongqing)

BACKGROUND: Human Borna disease virus (BDV) infections have recently been reported in China. BDV causes cognitive and behavioural disturbances in animals. The impact on human mental disorders is subject to debate, but previous studies worldwide have found neuropsychiatric patients more frequently infected than healthy controls. A few isolates were recovered from severely depressed patients, but contagiousness of BDV strain remains unknown. METHOD: We addressed the risk of infection in health care settings at the first affiliated hospital of Chongqing Medical University (CQMU), located in downtown Chongqing, a megacity in Southwest China. Between February 2012 and March 2013, we enrolled 1529 participants, of whom 534 were outpatients with major depressive disorder (MDD), 615 were hospital personnel, and 380 were healthy controls who underwent a health check. Infection was determined through BDV-specific circulating immune complexes (CIC), RNA, and selective antibodies (blood). RESULTS: One-fifth of the hospital staff (21.8%) were found to be infected (CIC positive), with the highest prevalence among psychiatry and oncology personnel, which is twice as many as were detected in the healthy control group (11.1%), and exceeds the prevalence detected in MDD patients (18.2%). CONCLUSION: BDV circulates unnoticed in hospital settings in China, putting medical staff at risk and warranting clarification of infection modes and introduction of prevention measures.