Transmission of GBV-C/HGV from drug-addicted mothers to their babies

Discovery of a Novel Simian Pegivirus in Common Marmosets (Callithrix jacchus) with Lymphocytic Enterocolitis

From 2010 to 2015, 73 common marmosets (Callithrix jacchus) housed at the Wisconsin National Primate Research Center (WNPRC) were diagnosed postmortem with lymphocytic enterocolitis. We used unbiased deep-sequencing to screen the blood of deceased enterocolitis-positive marmosets for viruses. In five out of eight common marmosets with lymphocytic enterocolitis, we discovered a novel pegivirus not present in ten matched, clinically normal controls. The novel virus, which we named Southwest bike trail virus (SOBV), is most closely related (68% nucleotide identity) to a strain of simian pegivirus A isolated from a three-striped night monkey (Aotus trivirgatus). We screened 146 living WNPRC common marmosets for SOBV, finding an overall prevalence of 34% (50/146). Over four years, 85 of these 146 animals died or were euthanized. Histological examination revealed 27 SOBV-positive marmosets from this cohort had lymphocytic enterocolitis, compared to 42 SOBV-negative marmosets, indicating no association between SOBV and disease in this cohort (p = 0.0798). We also detected SOBV in two of 33 (6%) clinically normal marmosets screened during transfer from the New England Primate Research Center, suggesting SOBV could be exerting confounding influences on comparisons of common marmoset studies from multiple colonies.

Detection and phylogenetic analysis of human pegivirus (GBV-C) among blood donors and patients infected with hepatitis B virus (HBV) in Qatar

Human Pegivirus (HPgV), formerly GB virus-C/Hepatitis G virus (GBV-C/HGV), collectively known as GBV-C, is widely spread and has been reported to be associated with non-A-E hepatitis. To our knowledge, no previous study was conducted about HPgV in Qatar. Thus, the objectives of this study were as follows: (i) to determine the rates of HPgV infection in Qatar among healthy blood donors and HBV-infected patients, and (ii) to determine the most predominant HPgV genotype in Qatar. A total of 714 blood plasma samples from healthy donors (612) and HBV-infected patients (102) were collected. RNA was extracted, reversed transcribed, and then subjected for HPgV detection by two round-nested PCR using primers amplifying a 208 bp of 5'-UTR of the HPgV. For genotyping, the 5'-UTR PCR products (from 25 randomly picked samples) were cloned and sequenced. The overall infection rate of HPgV in Qatar was 13.3%. There was no significant difference (P = 0.41) in the infection rates between healthy donor (13.7%) and in HBV-infected patients (10.7%). Moreover, we did not find any significant association between HPgV infection rates and nationality, sex, or age (P > 0.05). Sequence analysis of 40 5'-UTR PCR amplicons yielded the European genotype 2 as most predominant in Qatar, although other genotypes (5 and 7) were also present. Our results indicate that there is no strong correlation between HPgV infection rate, condition, nationality, age, and sex, and genotype 2 is most predominant in Qatar.

GB Virus C (GBV-C) Infection in Hepatitis C Virus (HCV) Seropositive Women with or at Risk for HIV Infection

Background

GB virus C (GBV-C) may have a beneficial impact on HIV disease progression; however, the epidemiologic characteristics of this virus are not well characterized. Behavioral factors and gender may lead to differential rates of GBV-C infection; yet, studies have rarely addressed GBV-C infections in women or racial/ethnic minorities. Therefore, we evaluated GBV-C RNA prevalence and genotype distribution in a large prospective study of high-risk women in the US.

Results

438 hepatitis C virus (HCV) seropositive women, including 306 HIV-infected and 132 HIV-uninfected women, from the HIV Epidemiologic Research Study were evaluated for GBV-C RNA. 347 (79.2%) women were GBV-C RNA negative, while 91 (20.8%) were GBV-C RNA positive. GBV-C positive women were younger than GBV-C negative women. Among 306 HIV-infected women, 70 (22.9%) women were HIV/GBV-C co-infected. Among HIV-infected women, the only significant difference between GBV-negative and GBV-positive women was age (mean 38.4 vs. 35.1 years; p<0.001). Median baseline CD4 cell counts and plasma HIV RNA levels were similar. The GBV-C genotypes were 1 (n = 31; 44.3%), 2 (n = 36; 51.4%), and 3 (n = 3; 4.3%). The distribution of GBV-C genotypes in co-infected women differed significantly by race/ethnicity. However, median CD4 cell counts and log₁₀ HIV RNA levels did not differ by GBV-C genotype. GBV-C incidence was 2.7% over a median follow-up of 2.9 (IQR: 1.5, 4.9) years, while GBV-C clearance was 35.7% over a median follow-up of 2.44 (1.4, 3.5) years. 4 women switched genotypes.

Conclusions

Age, injection drug use, a history of sex for money or drugs, and number of recent male sex partners were associated with GBV-C infection among all women in this analysis. However, CD4 cell count and HIV viral load of HIV/HCV/GBV-C co-infected women were not different although race was associated with GBV-C genotype.

GB virus C infection in pregnancy: maternal and perinatal importance of the infection

OBJECTIVES

The more effective way of transmission of GB virus C (GBV-C) is parenteral, but sexual and vertical transmission seem to be the main way of spreading. We evaluated the prevalence and the effect of GBV-C infection on pregnant women, vertical transmission and viral effects on the newborn.

STUDY DESIGN

This study has consecutively enrolled 879 pregnant women. All patients had blood sampling to determine GBV-C RNA, serologic tests for chronic viral infections and seric tests of hepatic damage. The newborns from infected mothers had blood sampling to detect the presence of GBV-C at birth, and after 3 and 6 months. Positive babies were checked until 18 months.

RESULTS

36 (4.1%) women resulted GBV-C positive. Among the positive patients none presented complications during pregnancy. Neither embryonic-fetal abnormalities nor relevant differences in fetal birth weight and week of gestation at delivery were found. 20 out of 36 babies had a follow-up. At birth, 13 (65%) babies were positive. 4 out of 9 vaginal deliveries (44%) and 9 out of 11 cesarean sections (82%) resulted positive to GBV-C RNA. The risk of GBV-C vertical transmission was not significantly increased by type of delivery (p=0.274). At 3 months, 13 babies were GBV-C positive (65%) and 7 were negative (35%). At the end of the follow-up, 9 babies were positive (45%), while 11 were negative (55%).

CONCLUSION

The percentage of patients positive to GBV-C RNA was comparatively high (4.1%). This prevalence, in a population without particular risk factors, confirms that common ways of transmission, such as the sexual and vertical ones, might have an important role in viral diffusion. Our data suggest that the infection does not influence the course of pregnancy. The rate of transmission found in our study is high. Type of delivery does not seem to be actually involved in vertical transmission and the protective role of cesarean section has not been confirmed.

The prevalence of GB virus C/hepatitis G virus RNA among healthy and HCV-infected Catalan children

GB virus C (GBV-C) is a blood-borne flavivirus. The prevalence of GBV-C viremia among healthy adults is 0.5% to 4% and, to date, no disease has been definitely associated with GBV-C infection. We conducted a cross-sectional study to evaluate GBV-C viremia prevalence in a group of 327 healthy children with normal alanine amino transferase (ALT) levels (Group A) and elevated ALT levels (Group B) of unknown origin, and among 38 pediatric patients with mother-to-child-transmitted hepatitis C virus (HCV) infection (Group C). No statistically significant differences were observed between prevalences in Groups A and B (2.2% vs 6.7%, p = 0.06). None of the children in Groups A or B who tested positive for GBV-C RNA showed any clinical symptoms. The prevalence of GBV-C viremia in Group A was lower than for patients in Group C (2.2% vs 13.2%, p = 0.007); no differences were observed in HCV infection characteristics between those patients who were co-infected with GBV-C and those who were not. In conclusion, while GBV-C viremia is more frequent among HCV-infected pediatric patients, it is neither associated with liver disease nor has any influence on HCV-related chronic hepatitis.

GB virus C genotype 1 is rarely transmitted vertically but acquired during infancy in West Africa

Paired Ghanaian plasma and cord blood from pregnant women, alongside plasma samples from children aged 1 day to 70 months, were tested for GBV-C, HIV-1 RNA loads and anti-E2. Frequency of GBV-C vertical transmission in West Africa is significantly lower than in Europe, the USA or East Asia where genotype 2 or 3 is prevalent. While horizontal transmission appears predominant in West Africa, the lower viral load of African genotype 1 might explain limited vertical transmission.

Detection and genotyping of GBV-C virus in the United Arab Emirates

GB virus-C/Hepatitis G virus (GBV-C/HGV), collectively known as GBV-C, is spread widely and has been reported to be associated with non A-E hepatitis. The aim of the current project was to determine the rate of infection and genotypic characteristics of GBV-C in the United Arab Emirates (UAE). A total of 379 plasma/serum samples representing different populations in the UAE and comprising healthy as well as patients positive for HBV and HCV were screened using RT-PCR/nested PCR of the 5'-untranslated region (UTR). National subjects (n=168) and non-nationals residing in the UAE (n=211) were tested. The results obtained showed that the rate of GBV-C infection in healthy nationals, and those positive for HCV or HBV were 11.1%, 14.3%, and 5.7%, respectively, compared to 8.3%, 33.3%, and 8.6%, respectively, in non-nationals. No statistically significant correlation between infection with GBV-C and HCV or HBV (P>0.05) was found. Sequence analysis of the 5'-UTR using 37 and 46 clones from 8 and 6 healthy nationals and non-nationals, respectively, revealed the prevalence of the European/North American genotype 2 when compared to the five reference genotypes in GenBank.

GB virus C coinfection and vertical transmission in HIV-infected mothers before the introduction of antiretroviral prophylaxis

OBJECTIVES

To investigate the prevalence of GB virus C (GBV-C) viraemia and GBV-C antibodies in a cohort of HIV-infected mothers and their infants between 1987 and 1994.

METHODS

GBV-C viraemia and antibodies were determined by polymerase chain reaction (PCR) and enzyme-linked immunosorbent assay (ELISA) in 52 HIV-infected mothers and their 53 infants, who were born before antiretroviral prophylaxis for reduction of HIV transmission was introduced at the end of 1994. Ten of these children acquired HIV.

RESULTS

Mothers of three children had GBV-C viraemia and mothers of another 14 children carried antibodies against GBV-C. No mother had GBV-C antibodies and GBV-C viraemia simultaneously. GBV-C viraemia was detected in only one infant. This child was delivered by the vaginal route to a mother with GBV-C viraemia, and was not HIV-infected. No vertical transmission of GBV-C occurred from mothers with GBV-C antibodies. However, four of 10 children who were infected with HIV had a mother with past or ongoing GBV-C infection.

CONCLUSION

Our findings suggest that the risk of vertical transmission of GBV-C is not elevated in HIV-infected mothers. Furthermore, although the number of HIV-1-infected children was low, we saw no evidence that the presence of ongoing or past GBV-C infection influenced the probability of vertical HIV transmission.

Genotype distribution of the GB virus C in citizens of São Paulo City, Brazil

There has been several studies worldwide on phylogenetics and genotype distribution of the GB-virus C / Hepatitis G virus (GBV-C/HGV). However, in their great majority, those investigations were based on some epidemiologically linked group, rather than on a representative sampling of the general population. The present is a continuation of the first study in Brazil with such a population; it addresses the GBV-C/HGV phylogenetics and genotype distribution based on samples identified among more than 1,000 individuals of the city of S o Paulo. For this purpose, a 728 bp fragment of the 5 non-coding region (5 NCR) of the viral genome, from 24 isolates, was sequenced and subjected to phylogenetic analysis. Genotypes 1, 2a and 2b were found at 8.3% (2/24), 50% (12/24) and 41.7% (10/24), respectively. In conclusion S o Paulo displays a genotype distribution similar to the published data for other States and Regions of Brazil, endorsing the notion that types 1 and 2 would have entered the country with African and European people, respectively, since its earliest formation.

Transmission of SEN virus from mothers to their babies

Sera from 30 women at high risk for infection, one half of which were SEN virus positive (SENV(+)), were collected at delivery to study SENV mother-to child transmission. Thirteen of their babies were positive for at least one SENV strain: one baby was SENV(+) at birth, eight became positive within 6 months from delivery, and four became positive in the following months. Our data indicate that vertical transmission of SENV does occur, presumably, at delivery, but it may not induce persistent viremia. This is supported by the fact that, generally, SENV is not detected at birth, by the high SENV homology in the sequences found in the mothers and in their children, by a lack of other risk factors for infection of the babies, and by the irregular detection of SENV in the follow-up. No clinical events surely linked to SENV infection were found, but transient elevations of alanine aminotransferase were observed in babies followed for a long period of time.

GB virus C/hepatitis G virus

GB virus C (GBV-C), or hepatitis G virus (HGV), is a recently discovered enveloped RNA virus belonging to the Flaviviridae family. GBV-C/HGV is transmitted by contaminated blood and/or blood products, intravenous drug use, from mother to child, sexually, and possibly through close social contacts. Several reports indicate a high prevalence of GBV-C/HGV viremia (1-4%) within healthy populations in Europe and North America, and an even higher prevalence (10-33%) among residents in South America and Africa. GBV-C/HGV has been suggested to be a causative agent for non-A-non-E hepatitis. However, several contradictory observations suggest that its ability to cause hepatitis is questionable. Taken together most data suggest that GBV-C/HGV is not a major cause of liver disease despite recent data indicating that it may infect and replicate in hepatocytes.

GB virus C/hepatitis G virus (GBV-C/HGV): still looking for a disease

GB Virus C and Hepatitis G Virus (GBV-C/HGV) are positive, single-stranded flaviviruses. GBV-C and HGV are independent isolates of the same virus. Transmission via the blood-borne route is the commonest mode, although vertical and sexual transmission is well documented. GBV-C/HGV is distributed globally; its prevalence in the general population is 10 fold higher in African countries than in non-African countries. High prevalences of GBV-C/HGV have been found in subjects with frequent parenteral exposure and in groups at high risk of exposure to blood and blood products. The clinical significance of human infection with GBV-C/HGV is currently unclear. The virus can establish both acute and chronic infection and appears to be sensitive to interferon. Only some 12-15% of chronic Non-A, B, C hepatitis cases are infected with GBV-C/HGV. A direct association with liver pathology is still lacking and it is not yet clear as to whether GBV-C/HGV is indeed a hepatotropic virus. Current evidence suggests that the spectrum of association of GBV-C/HGV infection with extrahepatic diseases ranges from haematalogical diseases, aplastic anaemia, human immunodeficiency virus (HIV)-positive idiopathic thrombocytopenia and thalassemia, through to common variable immune deficiency and cryoglobunemia.

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-CRNA, 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.

GB virus C/hepatitis G virus (GBV-C/HGV): still looking for a disease

GB Virus C and Hepatitis G Virus (GBV-C/HGV) are positive, single-stranded flaviviruses. GBV-C and HGV are independent isolates of the same virus. Transmission via the blood-borne route is the commonest mode, although vertical and sexual transmission is well documented. GBV-C/HGV is distributed globally; its prevalence in the general population is 10 fold higher in African countries than in non-African countries. High prevalences of GBV-C/HGV have been found in subjects with frequent parenteral exposure and in groups at high risk of exposure to blood and blood products. The clinical significance of human infection with GBV-C/HGV is currently unclear. The virus can establish both acute and chronic infection and appears to be sensitive to interferon. Only some 12-15% of chronic Non-A, B, C hepatitis cases are infected with GBV-C/HGV. A direct association with liver pathology is still lacking and it is not yet clear as to whether GBV-C/HGV is indeed a hepatotropic virus. Current evidence suggests that the spectrum of association of GBV-C/HGV infection with extrahepatic diseases ranges from haematalogical diseases, aplastic anaemia, human immunodeficiency virus (HIV)-positive idiopathic thrombocytopenia and thalassemia, through to common variable immune deficiency and cryoglobunemia.

High rate of GB virus type C/HGV transmission from mother to infant: possible implications for the prevalence of infection in blood donors

BACKGROUND

Because GB virus type C(GBV-C)/HGV (GBV-C/HGV) is blood-borne and sexually transmitted, persons at risk of infection with such viruses have a high prevalence of GBV-C/HGV markers. However, adults with no apparent risk factors, such as blood donors, frequently are positive for GBV-C/HGV markers. Mother-to-infant transmission could explain this high prevalence, but it has been studied only through small series of GBV-C/HGV-infected mothers co-infected with HCV or HIV.

STUDY DESIGN AND METHODS

To determine the rate of mother-to-infant transmission of GBV-C/HGV RNA in women who are HCV- or HIV-negative, a prospective study was performed in a cohort of 288 mothers screened for viral RNA and in the infants born to GBV-C/HGV-infected mothers.

RESULTS

Thirteen mothers (4.5%) were found positive for GBV-C/HGV RNA. Of the infants in whom at least one blood sample was collected between the third and the ninth months of life, 89 percent were positive for viral RNA. The majority of these newborns were negative for GBV-C/HGV RNA at birth and positive after the third month. The viral RNA titers of infants born to GBV-C/HGV-infected mothers appeared as elevated as those of their mothers. All the GBV-C/HGV-infected infants remained positive for viral RNA during the entire study period. No clinical events possibly linked to a primary GBV-C/HGV infection were reported in infants. Serum ALT level and blood count remained within normal values throughout the follow-up of all GBV-C/HGV-infected infants.

CONCLUSION

The frequency of mother-to-infant GBV-C/HGV transmission is elevated and could explain the high prevalence of GBV-C/HGV markers (viral RNA and E2 antibody) in adults at low risk for blood-borne or sexually transmitted viruses, such as blood donors.

The prevalence of serum GB virus C/hepatitis G virus RNA and anti-E2 in Japanese children without a history of blood transfusion

The prevalence of serum GB virus C (GBV-C)/Hepatitis G virus (HGV) RNA and anti-E2 was investigated in Japanese children younger than 16 years of age without a history of blood transfusion and the family members of serum GBV-C/HGV RNA-positive children. The prevalences of serum GBV-C/HGV RNA and anti-E2 were 0.5% (5/1000) and 0% (0/330), respectively. Viral RNA was also detected in the mothers of all five GBV-C/HGV RNA-positive children and in two of their siblings. Sequence determinations indicated the likelihood of mother-to-infant transmission in all cases. The presence of the virus persisted for at least 10-18 months in all 5 children, without any appearance of anti-E2.

Hepatitis G virus: molecular organization, methods of detection, prevalence, and disease association

This article reviews data on hepatitis G virus (HGV) prevalence and possible disease associations in various groups of patients. An important fraction of acute or chronic hepatitis cases probably have a viral etiology and are not attributable to known hepatitis viruses. Therefore, researchers continually are looking for new hepatitis viruses. Among the agents found are members of GB hepatitis viruses, including GB-C virus, or HGV. This review presents the history of the discovery of HGV, its molecular biology and some methods of detection; results of clinical and molecular studies of HGV infection also are discussed.

The hepatic flaviviridae: summary

Hepatitis C envelope proteins (E1, E2) induce protective neutralizing antibodies. The extent of sequence diversity reflects the host's ability to control viral populations and the response to antiviral therapy. Attempts to prepare effective vaccines against HCV are foiled by lack of prolonged protective immunity. Plasmid vaccines and the use of uninfectious virus-like particles are being developed. HCV induces a cellular humoral immune response, but this is inadequate to clear the virus and the disease becomes chronic. In any patient, the natural history of HCV infection depends on the age when infected, and the presence of other diseases. The transfusion-related disease has a worse prognosis than that transmitted by syringes and needles. The outlook in 'healthy blood donors' is uncertain. Interferon therapy for 3 or preferably 6 months results in a sustained response in about 30% of patients. Negative serum HCV RNA and normal AST values after 3 months of therapy indicates that there may be a sustained response. Whether or not to stop treatment at that time if HCV is still positive remains a matter of debate. The role of interferon treatment in preventing progression to cirrhosis and hepatocellular cancer is still uncertain. Ribavirin therapy alone reduces transaminases and hepatic histology improves. Improved results follow the combination of ribavirin with interferon. Ribavirin may have immuno-modularity and anti-inflammatory actions. Hepatitis G virus (HGV) is unlikely to play a significant role in liver disease in man.

Molecular evidence of mother-to-infant transmission of hepatitis G virus among women without known risk factors for parenteral infections

Hepatitis G virus (HGV) RNA was detected in 18 of 133 pregnant women from Tanzania without known risk factors for HGV infection and in 7 of 18 children born to HGV RNA-positive mothers. Molecular evidence of mother-to-infant transmission was obtained only for three of seven children. HGV RNA was also detected in 4 of 42 children born to non-HGV-infected women. Thus, mechanisms other than materno-filial may play an important role in HGV transmission during early childhood.

Hepatitis G virus infections in Iceland

This study describes the prevalence of hepatitisG virus (HGV) in Iceland, in blood donors and in persons with parenteral risk factors. Among 370 randomly selected Icelandic blood donors, the prevalence of HGV viraemia was 3.8%, whereas the prevalence of HGV antibodies in the same donor group was found to be 13.2%, thus indicating that at least 17% of blood donors in Iceland had previously been exposed to HGV. Previous exposure was seen in all age groups and also in older blood donors. Among intravenous drug users (IVDUs), the prevalence of HGV was much higher. Among 109 hepatitisC virus (HCV) antibody-positive serum samples collected in the years 1992-1997, 33. 9% were polymerase chain reaction (PCR)-positive for HGV and 48.6% had HGV antibodies. Thus, the pattern of HGV in IVDUs was similar to findings among IVDUs in other western countries. HGV viraemia was detected neither in 10 patients with haemophilia nor in five dialysis patients. However, six of the 10 haemophilic patients and one of the five dialysis patients had HGV antibody. In conclusion, unlike hepatitis C, which seems to have been introduced into Iceland relatively recently and has remained virtually confined to IVDUs, exposure to HGV is common among all age groups in the general population, suggesting that the virus has been prevalent in Iceland for much longer, making additional routes of transmission probable.

Inquiries on intraspousal transmission of hepatitis C virus: benefits and limitations of genome sequencing and phylogenetic analysis

During recent years, courts had to decide in some notable cases whether or not defendants infected the plaintiffs with HIV. Lawsuits on the transmission of other viral pathogens up to now have hardly become known. We report here on the use of genome sequencing and phylogenetic analysis to investigate possible intraspousal transmission of hepatitis C virus (HCV). The high degree of genetic relatedness observed in phylogenetic analysis among the HCV strains isolated from the couple demonstrates that the man and the woman are infected with the same isolate of the virus. After other plausible routes of infection have been virtually excluded by anamnestic and conventional epidemiological evaluation we could infer that the man most probably has infected his girlfriend with HCV. This conclusion was further supported by the finding that both are also infected with closely related isolates of GB virus C (GBV-C). Thus, the results from molecular biological investigations and epidemiological evaluation are complementary pieces of evidence in inquiries on possible intraspousal transmission of HCV.

GB virus type C infection in patients treated for childhood acute lymphoblastic leukemia

BACKGROUND

The purpose of this study was to determine the prevalence of GB virus type C (GBV-C) infection in subjects treated for childhood acute lymphoblastic leukemia (ALL) or non-Hodgkin's lymphoma.

STUDY DESIGN AND METHODS

One hundred forty patients (82 males) aged 4 to 27 years (median, 11) diagnosed with ALL between 1976 and 1993, were prospectively followed for a median of 5 years (range, 0.1-17) after completion of therapy. Stored sera were tested for antibody to hepatitis C virus (HCV), HCV RNA, antibody to GBV-C E2 (anti-E2), and GBV-C RNA.

RESULTS

Thirty-eight patients (27%) were exposed to GBV-C: 30 were positive for GBV-C RNA (mostly type 2) and 8 were positive for anti-E2. Anti-E2 and GBV-C RNA were mutually exclusive: 61 patients (43%) were positive for HCV RNA, 16 (11%) were coinfected with GBV-C and HCV. Alanine aminotransferase (ALT) levels were increased (>35 mU/mL) in 32 (23%) of 137: 3 of 20 who were positive for GBV-C and negative for HCV, 7 of 15 who were positive for GBV-C and HCV, 15 of 44 who were negative for GBV-C and positive for HCV, and 7 of 58 who were negative for GBV-C and HCV (p<0.001). Median ALT values were significantly higher in patients positive for GBV-C and HCV than in those who were positive for GBV-C and negative for HCV (35 vs. 13 mU/mL, p = 0.003). Thirty-one of 38 patients with GBV-C markers were retested: GBV-C RNA was lost in 16 of 30 tested, but 7 were still GBV-C RNA positive up to 50 months later, 3 tested positive for anti-E2 up to 27 months later, and 1 was positive for GBV-C RNA and anti-E2 26 months later, while 20 tested negative for both.

CONCLUSION

GBV-C did not behave as a liver pathogen, because ALT alterations were unrelated to GBV-C status, but, rather, were related to HCV infection or coinfection. GBV-C RNA was frequently lost over a relatively short period, though in some cases, it was retained for a longer time. Anti-E2 rarely coexisted with GBV-C RNA and might be short-term.

Prevalence of GB virus type C/hepatitis G virus RNA and anti-E2 among blood donors in Southeastern France

BACKGROUND

The purpose of the study was to analyze serologic and molecular markers of the GB virus type C/hepatitis G virus (GBV-C/HGV) infection in voluntary blood donors from Southeastern France.

STUDY DESIGN AND METHODS

Sera were tested for the presence of GBV-C/HGV RNA by reverse transcriptase-polymerase chain reaction and that of antibodies to the GBV-C/HGV E2 (anti-E2) antigen by an enzyme-linked immunosorbent assay. A first cohort (1660 blood donors) was tested prospectively and a second cohort (238 samples with hepatitis markers) was tested retrospectively. Donors in the prospective study were questioned for possible risk factors of virus transmission. Amplification products were sequenced and subjected to phylogenetic analysis.

RESULTS

Approximately 2.6 percent of individuals accepted for blood donation and 15.4 percent with positive hepatitis C virus serologic tests carried GBV-C/HGV RNA. Anti-E2 was detected in these two populations in approximately 12 percent and 48 percent of donors, respectively. Moderate relative risks were found only in tattooed or pierced individuals (1.82) and health care workers (2.45). Almost all strains were located in the same phylogenetic branch as HGV Group 2.

CONCLUSION

Though a large proportion of the donors tested have been in contact with GBV-C/HGV, no elevated relative risk of infection was identified. The phylogenetic distribution of viral strains suggests that the infection is endemic in this population.

HGV/GBV-C infection in liver transplant recipients: antibodies to the viral E2 envelope glycoprotein protect from de novo infection

BACKGROUND/AIMS

Liver transplantation for endstage liver cirrhosis provides a useful model to investigate the pathogenetic role of hepatotropic viral agents. Recently, a new member of the Flaviviridae family, provisionally named HGV/GBV-C virus, has been associated with acute and chronic non A-E hepatitis. We studied 136 patients with cirrhosis consecutively transplanted at our institution for evidence of hepatitis G virus infection and correlation with the patients' clinical course.

METHODS

All patients survived for at least 6 months after transplantation (median follow-up 44 months) and underwent routine liver biopsies. Hepatitis G virus infection was studied using both direct viral RNA identification by RT-PCR and indirect detection of antibodies to the E2 glycoprotein.

RESULTS

There was a high frequency of the hepatitis G virus among patients undergoing liver transplantation, with HGV RNA and anti-E2 prevalence rates of 18.4% and 26.5%, respectively. HGV RNA prevalences significantly increased after transplantation (47.8%), with 47.3% rate of new infections in susceptible subjects. Anti-E2 antibodies were significantly more prevalent among patients transplanted for HCV-related cirrhosis and represented a strong protective factor against hepatitis G virus reinfection or recurrent infection. No correlation was found between HGV RNA or anti-E2 prevalences and survival after transplantation or rates of recurrent liver damage.

CONCLUSIONS

All available evidence suggests that, although liver transplant patients are heavily exposed to hepatitis G virus both before and after transplantation, hepatitis G virus does not induce liver disease in this setting. Most infections appear to be self-limited and induce a protective immunity which is marked by the presence of anti-E2 antibodies.

Prevalence of GBV-C/HGV infection in pregnant Japanese women

Recently, a novel viral agent, hepatitis G virus, was identified by independent researchers from the serum of patients with liver disease, and termed GBV-C or HGV. At present, GBV-C and HGV are considered to be separate isolates of the same virus; however, the role of this virus in acute and chronic liver disease remains uncertain. Although vertical transmission is known to be one of the routes of transmission, the prevalence of GBV-C/HGV viremia in pregnant Japanese women is unknown. Thus, we determined this prevalence using the reverse transcription polymerase chain reaction (RT-PCR).

Natural history and molecular biology of hepatitis G virus/GB virus C

BACKGROUND

The hepatitis G virus (HGV) or GB virus C (GBV-C) is a new member of the Flaviviridae family. The virus is transmitted by transfusion of blood, infusion of some blood products, and by parenteral exposure to blood during intravenous drug use (IVDU) and haemodialysis. Transmission from mother to infant and by sexual contact has also been documented. Although the virus has been found in patients with acute and chronic hepatitis, evidence of disease association has not been forthcoming. The majority of patients carry the virus in the absence of liver enzyme abnormalities.

OBJECTIVES

To review what is currently known about HGV/GBV-C in order to evaluate its similarity with other members of the Flaviviridae and the association of the virus with disease.

RESULTS

The genomic organisation of the virus is typical for Flaviviridae, with long 5' and 3' untranslated regions (UTR). However, a clearly identifiable nucleocapsid encoding region is lacking. Polyprotein synthesis is mediated through an internal ribosome entry site (IRES) contained within the 5' UTR. Phylogenetic tree analysis of sequences derived from this region has demonstrated the existence of at least three genotypes. Apart from serum, HGV-RNA has been detected in lymphocytes also, but the quasispecies present in the two compartments appear to be different. The envelope glycoprotein E2 lacks a hypervariable region and is potentially the target of a neutralising antibody response.

CONCLUSION

Molecular analysis of HGV reveals close similarity of the virus with HCV. However, an association of the virus with liver disease remains unresolved and no association of the virus with hepatocellular carcinoma has been reported.

Hepatitis G virus infection in Amerindians and other Venezuelan high-risk groups

Recently, a new virus related to flaviviruses, the hepatitis G virus (HGV), or GBV-C virus, was discovered as a putative blood-borne human pathogen. HGV RNA (NS5 region) was amplified by reverse transcription-nested PCR in the sera of 6 of 64 (9%) hemodialysis patients; 2 of 80 (2.5%) West Yukpa Amerindians, a population with a high rate of HBV infection but negative for HCV infection; and 1 patient with an acute episode of non-A, non-B, non-C hepatitis (NABCH). The patterns of single-strand conformation polymorphism of the amplified products were unique among different specimens and similar on follow-up for hemodialysis patients. All patients tested remained HGV RNA positive 1 and 2 years later, without major sequence variation, except for the NABCH patient, for whom a double infection and an apparent clearance of the original dominant variant was observed after 2 years. The sequences of the NS5 amplified products demonstrated 85 to 90% identity with other reported HGV sequences.

Multicenter trial on mother-to-infant transmission of GBV-C virus. The Lombardy Study Group on Vertical/Perinatal Hepatitis Viruses Transmission

Evidence indicates that the GBV-C or hepatitis G virus can cause persistent infection in humans, but little is known on the importance of vertical transmission. To assess the risk of mother-to-infant transmission and the clinical outcome of infected babies, we investigated 175 anti-HCV positive mothers and followed-up their children for 3-33 months. GBV-C RNA was detected by RT-PCR and anti-E2 antibody was assayed by EIA. Thirty-four (19.4%) women were GBV-C RNA positive and transmission occurred to 21 (61.8%) babies; 20 (95.2%) acquired GBV-C alone, and one (4.8%) GBV-C and HCV. Maternal factors such as intravenous drug use, HIV coinfection, HCV-RNA positivity, and type of feeding were not correlated with GBV-C transmission. GBV-C RNA remained persistently positive in all infected babies but one baby who seroconverted to anti-E2. Seven (35%) babies with GBV-C alone developed marginally elevated ALT; the baby with HCV and GBV-C co-infection had the highest ALT peak value (664 IU/l). Seven of the 141 (5%) babies born to the GBV-C RNA negative mothers acquired HCV and six (85.7%) had abnormal ALT. The mean ALT peak value was significantly higher (P < 0.05) for babies with HCV than for those with GBV-C. None of the children with GBV-C or with HCV became icteric. GBV-C is frequently present in anti-HCV positive women. The infection is transmitted efficiently from mother to baby and rate of transmission is much higher than that for HCV. GBV-C can cause persistent infection in babies but usually without clear evidence of liver disease.

Detection of GBV-C/HGV RNA in saliva and serum, but not in urine of infected patients

Saliva and urine samples from six GB virus C (GBV-C)/hepatitis G virus (HGV)-infected renal transplant patients were tested by RT-PCR. Viral RNA was detected in all saliva samples, but the viral RNA titers in saliva were 100 to 10,000 lower than those in the corresponding sera. Comparative sequence analysis of the amplified 354 bp DNA from one patient revealed full identity of GBV-C/HGV variants present in serum and saliva. None of the urine samples from the six patients was found to contain GBV-C/HGV RNA. High prevalence of GBV-C/HGV RNA in saliva of infected individuals may contribute to a wide spread of GBV-C/HGV infection, at least in some settings.