Preliminary Seroepidemiological And Molecular Epidemiological Study Of Human Borna Disease Virus Infection In Chongqing

Background:Borna disease virus (BDV) is negative single-strand RNA virus, whichis non-cytotoxic and highly neurotropic. The virus could persistently infectcentral nervous system. BDV could infect a variety of warm-blood hostssuch as horse, rabbit, mice and dog. Animals infected with BDV could showobvious mental, behavioral disorders and other neuropsychiatric symptoms.Recently a large number of domestic and international epidemiologicalstudies focus on the relationship between human with BDV, in which manystudies showed the evidence that human could be infected with BDV.Meanwhile based on serum and molecular epidemiological studies, theinfection of BDV is considered the pathogenesis of a variety of mentalillness such as major depressive disorder.ObjectiveWe enrolled patients who were diagnosed as major depressive disorderand healthy people in Chongqing as participants in the study. Serologicaland molecular epidemiological research methods were performed toexplore the pattern of human BDV infection in Chongqing. And also, the distribution of BDV infection was compared between patients with majordepressive disorder and healthy people.Method1. Participants enrolled: In this study914participants were enrolled,which included534patients with major depressive disorder (187males,347females) and380healthy people (160males,220females). All theparticipants had been sifted by rigorous inclusion and exclusion criteria.2. Serologic detection: We performed ELISA method to detect BDVcirculating immune complexes (CICs) in plasma，which has been reportedpreviously. Each plasma sample was tested twice, the final result was takenas the average of the two repeated tests.3. Molecular biological detection: Molecular biological marker ofBDV infection was detected in all914blood samples. We extracted RNAfrom the whole blood samples, then perform reverse transcription to getcDNA. Subsequently we detected p24fragment by performing fluorogenicprobe RT-PCR.Result1. Serological test: BDV circulating immune complexes were detectedin139samples, the positive rate was15.2%. All these positive samplesincluded42healthy people (11.1%) and97patients with major depressivedisorder (18.2%). The positive rate was significantly different between thetwo groups (X~2=5.093, P=0.024). 2. Molecular biology test results: Overall35positive samples weredetected, the positive rate was3.8%. All these positive samples included8healthy people (2.1%) and27patients with major depressive disorder(5.1%). The positive rate was significantly different between the twogroups (X~2＝5.250，P=0.022).Conclusion1. This study firstly reported epidemiology data of human BDVinfection in Chongqing, which included depressed patients and healthypeople.2. This study showed that rate of BDV infection in patients with majordepressive disorder was significantly higher than that of healthy people,which was identical to the related foreign researches.