fox.rrq4a ua Er'rrrapcKara aKaAeMrls Ha HaJrKr{Te Comptes rendus de ltAcad6mie bulgare des Sciences Tome 67, IYo8, 2014 MEDECINE M6decine clinique PCR SYSTEMS FOR DETECTION OF NOVEL ELUSIVE HUMAN PATHOGENS TORQUE TENO VIRUSES (TTVs) IN BULGARIA Kalina Shishkova, Iliya Tsekov*, Rumen Popov**, Stoyan Shishkov, Zlatko Kalvatchev* (Submitted by Corresponding Member O. Poljakova-Krusteva on April 30, 2014) Abstract TT virus is a newly described agent infecting humans. Initially isolated from a patient (initials T. T.) with unexpiained hepatitis, the virus has since been found in both healthy and diseased individuals. The objective of our study was to apply effective TTV PCR detection system in order to analyse and prove its presence in biood samples among patients with: hepatitis, brain tumour, respiratory diseases,unknown pathology cases, renal transplantation and volunteer blood donors in Bulgaria. The most sensitive of the PCR assays was utilised to demonstrate the prevalence of TT viruses to be at least 6I.57% in volunteer blood donors, 62.74%in patients with respiratory diseases,65.2lTo in hepatitis cases, 62.96% in unknown pathology cases, 66.66% in patients with brain tumour and 64.28% in patients with renal transplantation. This is the first report demonstrating the TT viruses in Bulgaria. Key words: TT virus, detection system, TTV prevalence Introduction. In 1997 a novel DNA virus, unrelated to the known human viruses, was isolated by representational difference analysis from the serum of a patient with post-transfusion hepatitis of unknown aetiology, and it was named as TT virus (TTV) after the initials (T. T.) of the patient [1]. TTV has been classified into a new family called Anelloviridae [2]. In 2000 Torque Teno Mini Virus (TTMV) was accidentally discovered in the serum of a blood donor by PCR using TTV-specific primers that partially matched homologous sequences in TTMV but generated a noticeably shorter amplicon than that expected for TTV. In 2007 a small virus was found, related to the known two viruses, which 1t75