Prevalence of GBV-C/hepatitis G virus viremia and anti-E2 in Canadian blood donors

BACKGROUND AND OBJECTIVES: GB virus C (GBV-C)/hepatitis G virus (HGV) is a recently recognized parenterally and sexually transmitted agent. The prevalence of GBV-C/HGV markers in Canadian blood donors has not been previously studied and was therefore determined. MATERIALS AND METHODS: Blood donors [identity unlinked (IU), short-term temporarily deferred (STTD) and autologous groups] and donor samples with antibodies to hepatitis C (anti-HCV) or hepatitis B core were tested for GBV-C/HGV RNA and for antibodies to E2 antigen (anti-E2). RESULTS: GBV-C/HGV RNA was found in 1.1% and anti-E2 in 7.3% of the combined IU/STTD donor group. Viremia was much more common in anti-HCV-positive samples (12.5%); anti-E2 was present in >50% of this group. In the STTD group, female gender was significantly associated with viremia. CONCLUSION: GBV-C/HGV infection is relatively common in Canadian donors, and a small proportion are viremic. The association of female gender and viremia was unexpected. Further study is needed to clarify the epidemiology and natural history of GBV-C/HGV infection.     

A case-control study of transmission routes for GB virus C/hepatitis G virus in Swedish blood donors lacking markers for hepatitis C virus infection.

BACKGROUND AND OBJECTIVES: The transmission routes for GB virus-C (GBV-C)/hepatitis G virus (HGV) in blood donors unexposed to hepatitis C virus (HCV) are unknown. We performed a case-control study of risk factors for GBV-C/HGV exposure in blood donors. MATERIALS AND METHODS: After testing stored sera from 458 HCV-negative blood donors for GBV-C/HGV RNA and GBV-C/HGV E2 antibodies, 66 donors with GBV-C/HGV markers and 125 age- and gender-matched controls were interviewed regarding risk factors for viral transmission. RESULTS: Exposure to GBV-C/HGV was strongly associated with previous treatment for a sexually transmitted disease (odds ratio [OR] 4.6; 95% confidence interval [CI] 2.2-9.8), with multiple sexual partners (OR 2.9; 95% CI 1.4-5.7) and with a past history of endoscopy (OR 7.0; 95% CI 3.0-16.4). CONCLUSIONS: In blood donors with GBV-C/HGV markers, sexual contacts and medical procedures appear to be the main transmission routes.     

Assessment of liver disease and biochemical and immunological markers in Swedish blood donors with isolated GB virus C/hepatitis G virus viremia

OBJECTIVE: To investigate signs of liver disease, and biochemical and immunological markers in blood donors with isolated GBV-C/HGV viremia. METHODS: Eighteen donors with isolated GBV-C/HGV viremia were followed up 3-5 years after initial identification. Testing for GBV-C/HGV RNA, GBV-C/HGV-E2 antibodies and a range of biochemical and immunological tests was performed. Thirteen donors consented to liver biopsy. RESULTS: Twelve donors remained GBV-C/HGV viremic at follow-up. Five donors had developed E2 antibodies. Liver biopsies revealed mild portal inflammatory lesions in 6/11 individuals with persistent viremia, and steatosis in 10/13 biopsied donors. CONCLUSION: Steatosis and mild portal inflammatory lesions were found in liver biopsies from several blood donors with isolated GBV-C/HGV viremia.     

GB virus C/Hepatitis G virus infection is frequent in American children and young adults.

The novel flavivirus GB virus C/hepatitis G virus (GBV-C/HGV) has been detected in approximately 2% of blood donors in the United States, and neutralizing antibody to the envelope protein (E2), a marker of previous infection with GBV-C/HGV, is present in approximately 9% of donors. The rate of GBV-C/HGV infection among American children is unknown. To determine whether viral infection might occur during childhood, 160 serum specimens (obtained from blood bank samples) from children and young adults with no history of transfusion were tested. Viral RNA and antibody to E2 were detected in 6.3% and 9.4% of subjects, respectively. Evidence of previous or current infection (viremia and/or antibody to E2) was detected in 13.8% of subjects, indicating that GBV-C/HGV infection appears to be common among American children and young adults, even in the absence of blood transfusion.     

肝炎病人血清、外周血单个核细胞和肝脏中GBV-C/HGV复制中间体的研究

目的:关于GBV-C/HGV组织亲和性的研究尚无结论性资料。我们研究27例肝炎病人血清、外周血单个核细胞(PBMCs)及肝脏中GBV-C/HGV正链及负链RNA(复制中间体)的存在状况。方法:应用逆转录-巢式多聚酶链反应技术检测GBV-C/HGV正、负链RNA。结果:27例病人血清中21例病人血清、7例PBMCs、10例肝组织中检测到GBV-C/HGV正链RNA,其中2例单一GBV-C/HGV感染者肝组织中检测到负链RNA,在27例病人血清及PBMCs中均未检测到负链RNA。结论:提示GBV-C/HGV是一种嗜肝病毒,肝脏可能是其复制的主要场所之一,但GBV-C/HGV与HCV混合感染时,在PBMCs及肝脏中尚未发现该病毒复制的证据。     

A high frequency of GBV-C/HGV coinfection in hepatitis C patients in Germany

AIM:To detect infection rate of GBV-C/HGV in hepatitis C patients, to determine the methods of higher sensitivity and the primers of higher efficiency for GBV-C/HGV RNA detection and to study the dominant subtype and mutation of GBV-C/HGV.METHODS:Quantitative RT-PCR for detection pf HCV RNA concentration in serum samples, RT-nested PCR with two sets of primers for detection of GBV-C RNA, RT-PCR ELISA with two sets of primers for detection of HGV RNA, nucleotide sequence and putative amino acid sequence analysis.RESULTS:The positive rates of GBV-C RNA at the 5'-NCR and NS3 region in 211 serums amples from the patients with HCV infection were 31.8% and 22.8% respectively. The positive rates of HGV RNA at the 5'-NCR and NS5 region in the same samples were 47.9% and 31.8% respectively. The total positive rate of GBV-C/HGV RNA was as high as 55.5%. HCV copy numbers in the patients without GBV-C/HGV coinfection were statistically higher than that in the patients with GBV-C/HGV coinfection (P<0.01).Frequent mutation of nucleotide residue was present in the amplification products. Frameshift mutation was found in two samples with GBV-C NS3 region nucleotide sequences. All nucleotide sequences from amplification products showed higher homology to HGV genome than to GBV-C genome even though part of the sequences were amplified with GBV-C primers.CONCLUSION:A high frequency of GBV-C/HGV coinfection existed in the hepatitis C patients. RT-PCR ELISA was more sensitive than RT-nested PCR for detection of GBV-C/HGV RNA. The primers derived from the 5'-NCR was more efficient than those derived from the NS3 and NS5 regions. A reverse relationship was found to exist between HCV RNA concentration and GBV-C/HGV infection frequency. HGV was the dominant subtype of the virus in the local area. The major mutations of GBV-C/HGV genomes were random mutation of nucleotide residue.     

聚合酶链反应和杂交试验检测上海地区庚型肝炎病毒感染的初步报告

为探讨上海地区庚型肝炎病毒感染的现状，采用逆转录套式聚合酶链反应（ＲＴＮｅｓｔｅｄＰＣＲ）检测庚型肝炎病毒（ＨＧＶ／ＧＢＶＣ）核酸（ＨＧＶＲＮＡ）。结果在各类患者和助血员中ＨＧＶＲＮＡ的检出率分别是：血液透析和肾移植为１５７％（８／５１）、丙型肝炎为３３％（１／３０）、乙型肝炎为０（０／１９）、散发性非Ａ～Ｅ型肝炎为０（０／２８）、义务助血员为７５％（５／６７）。提示ＨＧＶ感染多为无症状或亚临床型，常与ＨＣＶ重叠感染，并与输血密切相关。作者肯定了上海地区存在庚型肝炎，指出筛选助血员对控制输血后庚型肝炎至关重要。     

Status and natural course of GB virus C/hepatitis G virus infection among high-risk groups and volunteer blood donors in Taiwan

BACKGROUND: Hemophilia, thalassemia and uremia patients are at risk of parenterally transmitted infectious agents. The status and nature of the course of GB virus C/hepatitis G virus (GBV-C/HGV) infection among these groups and blood donors in Taiwan was investigated. METHODS: Serum GBV-C HGV-RNA and antibodies to GBV-C/HGV envelope-2-protein (anti-E2) were determined in 500 blood donors and in 44 hemophilia, 37 thalassemia and 85 uremia patients. Phylogenetic analysis was performed. RESULTS: The prevalence of GBV-C/HGV-RNA and anti-E2, respectively, was 38.6 and 27.3% in hemophilia patients, 27.0 and 27.3% in thalassemia patients, 14.1 and 10.6% in uremia patients and 3.4 and 7.2% in blood donors. The prevalence of GBV-C HGV exposure was 59.1 and 51.4% in hemophilia and thalassemia patients, respectively, which was significantly higher than that for uremia patients (22.4%; P < 0.01) and blood donors (10.2%; P < 0.001). The anti-E2 seroconversion rate was 66.7% in blood donors and 47.4, 36.8 and 34.6% in thalassemia, uremia (P < 0.05 compared with blood donors) and hemophilia (P < 0.01 compared with blood donors) patients, respectively. Discrepancies in the prevalence of GBV-C HGV and hepatitis C virus infection were found among the three risk groups. Phylogenetic analysis showed that 51 of 56 GBV-C HGV isolates clustered in group 3; the remaining five were of group 2a. Twelve of 39 viremic patients in the risk groups cleared the virus during the 4 year follow-up period; seven developed concomitant anti-E2 reactivity. CONCLUSIONS: GB virus C hepatitis G virus infection is epidemic among risk groups and GBV-C HGV group 3 is the major strain in Taiwan. In the risk groups, approximately 18% of infections resolve with concomitant anti-E2 seroconversion within 4 years.     

Prevalence of GBV C/HGV RNA and GBV C/HGV Antibodies in French Volunteer Blood Donors: Results of a Collaborative Study

BACKGROUND AND OBJECTIVES: Posttransfusion hepatitis still occurs at an incidence of about 1 in 118,000 for HBV and 1 in 220,000 for HCV. This collaborative study aimed to determine the prevalence of a novel flavivirus, GBV-C/HGV, even though its role in transfusion-associated hepatitis is uncertain. MATERIALS AND METHODS: GBV-C/HGV RNA was detected by PCR using either the Boehringer detection kit or by primers previously described. HGV antibodies were detected by a serological assay from Boehringer. RESULTS: The observed GBV-C/HGV RNA frequency was 3.4%. HGV antibodies occurred in 9.5% of donors. CONCLUSION: In our study, 12. 9% of the donors had been in contact with the GBV-C/HGV virus.     

High frequencies of HGV and TTV infections in blood donors in Hangzhou

AIM: To determine the frequencies of HGV and TTV infections in blood donors in Hangzhou. METHODS: RT-nested PCR for HGV RNA detection and semi-nested PCR for TTV DNA detection in the sera from 203 blood donors, and nucleotide sequence analysis were performed. RESULTS: Thirty-two (15.8%) and 30 (14.8%) of the 203 serum samples were positive for HGV RNA and TTV DNA, respectively. And 5 (2.5%) of the 203 serum samples were detectable for both HGV RNA and TTV DNA. Homology of the nucleotide sequences of HGV RT-nested PCR products and TTV semi-nested PCR products from 3 serum samples compared with the reported HGV and TTV sequences was 89.36%, 87.94%, 88.65% and 63.51%, 65.77% and 67.12%, respectively. CONCLUSION: The infection rates of HGV and/or TTV in blood donors are relatively high, and to establish HGV and TTV examinations to screen blood donors is needed for transfusion security. The genomic heterogeneity of TTV or HGV is present in the isolates from different areas.     

Hepatitis G virus genotypes in Australia, Papua New Guinea and the Solomon Islands: a possible new Pacific type identified

BACKGROUND: Hepatitis G Virus (HGV)/GB Virus-C (GBV-C) is a newly discovered RNA virus. Nucleotide sequence comparison and phylogenetic studies of the 5' untranslated region (5'UTR) within the viral genome have identified at least three different types which have provisionally been classified as type 1 (West African origin), type 2 (North American origin) and type 3 (Asian origin). METHODS AND RESULTS: The products of RT-PCR were sequenced by using blood donors and patients infected with HGV/GBV-C in Australia, Papua New Guinea and the Solomon Islands to investigate the genotype distribution in this area of the world. All the Australian isolates showed strong sequence homology with type 2, while the Papua New Guinea and Solomon Islands sequences were more closely related, but differ from type 3, which has previously been reported from isolates studied within Asia. CONCLUSIONS: Phylogenetic analysis suggests that these latter sequences are either a new HGV/GBV-C Pacific type or a subtype of the Asian type RNA virus. Isolates homologous with type 1 were not identified in these population groups.