Zehender G, Manzin A, De Maddalena C, Colasante C, Solforosi L, Corsi F, Bianchi-Bosisio A, Girotto M, Schirru I, Russo U, Galli M, Clementi M
Istituto di Malattie Infettive e Tropicali, Universita' degli Studi di Milano, Milan, Italy.
J Med Virol. 2001 Jan;63(1):76-84.
The prevalence and genotype distribution of human TT virus (TTV) in Italy were analysed in 593 subjects at different risk of parenteral infection who included blood donors, patients with chronic type C hepatitis (HCV), thalassemic patients, patients on haemodialysis, human immunodeficiency virus type 1 (HIV-1)-negative intravenous drug users (IVDUs), and HIV-1-infected subjects (IVDUs, heterosexual contacts and homosexual males). Plasma TTV-DNA was detected using nested PCR with primers deduced from the N22 region of the open reading frame 1 (ORF-1) and from the untranslated region (UTR) of the viral genome. Phylogenetic analysis of the sequences obtained from ORF-1 was also undertaken. A high prevalence of plasma TTV-DNA was observed using the UTR primers, with rates varying from 83-100% in the study groups. Using the N22 primers, HIV-1 positive IVDUs and homosexual males, haemodialysed patients and thalassemic patients had a significantly higher TTV prevalence (range: 23.0-86.1%) than blood donors, who displayed a high frequency of positivity (10.6%). Sequence analysis of 127 N22-positive isolates revealed that 42.5% were of type 1, 53.5% of type 2, 2.4% of type 3, and that two isolates (1.6%) were closely related to genotypes 1-2 but distinct from the other major genotypes. TTV-2 was significantly more prevalent in patients at high risk for parenteral infection and in HIV-1 positive homosexuals. In sequential samples from 15 TTV-infected subjects, N22 sequences were detectable persistently in 12 (80.0%) and UTR sequences persisted in all 15 patients over a mean period of 29.6 months. This data indicates that TTV is widespread in Italy in parenterally exposed subjects, and that the infection frequently persists.
对意大利593名有不同经肠感染风险的受试者进行了人类细小病毒TTV（TTV）的流行率和基因型分布分析，这些受试者包括献血者、慢性丙型肝炎（HCV）患者、地中海贫血患者、接受血液透析的患者、1型人类免疫缺陷病毒（HIV-1）阴性的静脉吸毒者（IVDU）以及HIV-1感染受试者（IVDU、异性接触者和男同性恋者）。使用巢式PCR检测血浆TTV-DNA，所用引物推导自开放阅读框1（ORF-1）的N22区域和病毒基因组的非翻译区域（UTR）。还对从ORF-1获得的序列进行了系统发育分析。使用UTR引物观察到血浆TTV-DNA的高流行率，各研究组的流行率在83%至100%之间。使用N22引物时，HIV-1阳性的IVDU和男同性恋者、接受血液透析的患者和地中海贫血患者的TTV流行率（范围：23.0%至86.1%）显著高于献血者，献血者的阳性频率较高（10.6%）。对127株N22阳性分离株的序列分析显示，42.5%为1型，53.5%为2型，2.4%为3型，有两株分离株（1.6%）与1-2型基因型密切相关，但与其他主要基因型不同。TTV-2在经肠感染高风险患者和HIV-1阳性男同性恋者中显著更为普遍。在15名TTV感染受试者的连续样本中，12名（80.0%）可持续检测到N22序列，所有15名患者在平均29.6个月的时间内均持续存在UTR序列。该数据表明，TTV在意大利经肠暴露的受试者中广泛存在，且感染常常持续存在。
