Genomic characterization of hepatitis C virus isolates from Argentina

Thirty-three Argentinian patients infected with hepatitis C virus (HCV) were studied for viral genotyping. The patients included 10 hemophiliac and 4 polytransfused children and 19 adults: 3 polytransfused, 7 dialyzed and 9 sporadic cases. Core-based genotyping permitted the classification of 31 samples. Genotypes II, I and V were the most frequent: 21 (63.6%), 16 (48.4%) and 10 (30.3%) of the 33 patients, respectively. Only one polytransfused patient carried genotype IV. Genotype II was detected in 7 out of 9 sporadic cases. Thirteen patients (39.3%) were coinfected with two genotypes, and 2 others were coinfected with three genotypes. The remaining 2 samples which could not be typed were characterized following the restriction fragment length polymorphism (RFLP) method, and were classified as type 1. One of these had two consecutive transitional mutations in the 5′ untranslated region (5′ UTR). © 1995 Wiley-Liss, Inc.     

Contrasting patterns of hepatitis C virus infection in two regions from Tunisia

This report is a population-based study describing the pattern of hepatitis C virus (HCV) infection in two distinct regions in Tunisia. The study included a total of 11,507 individuals sampled in 1996 from both genders, all age groups, urban and rural settings belonging to 2,973 families. HCV infection was assessed by commercial enzyme immunoassay (EIA) and immunoblot assays and detection of HCV RNA by PCR. HCV genotypes and subtypes were determined by sequencing in the 5'-untranslated region (UTR) viral genomic region and the INNO-LiPA HCVII genotyping kit. Genetic relatedness between HCV strains was assessed by sequencing of a portion of the NS5B region. HCV prevalence was significantly higher in the North-Western region than in the Southern one: 1.7% versus 0.2% (P < 10(-3), chi(2) = 8,506). There was no difference in positivity according to gender or living in rural or urban settings; the only significant risk factor was advanced age. HCV prevalence among household contacts of HCV positives was not significantly higher than the prevalence in the whole study population. These results indicate a heterogeneity in the geographical distribution of HCV in Tunisia. An increased HCV transmission occurs in the North-Western region with large predominance of genotype 1b (88%) and low contribution of intrafamilial transmission.     

Genetic heterogeneity of hepatitis E virus

Hepatitis E virus (HEV) infection has been considered a disease associated with developing regions and attributed to oral-fecal transmission due to inadequate sanitation. Several recent findings, however, have led to a new understanding of this virus. A number of novel isolates have been identified in patients with acute hepatitis from regions not considered endemic for HEV, and these individuals reported no recent travel to HEV endemic areas. In addition, a number of HEV-like sequences have also been isolated from swine worldwide, suggesting the potential of an animal reservoir. Although full-length sequence is available for some strains, the majority of HEV isolates have only been sequenced partially. Sequence comparisons and phylogenetic analyses were performed to determine the genotypic distribution of HEV isolates, based on the partial sequence data available. It has been suggested that HEV isolates segregate into four major genotypes based on full-length comparisons. These analyses, however, indicate that HEV may be distributed into at least nine different groups.     

GB virus type C infection in hemodialysis patients considering co-infection with hepatitis C virus

GB virus type C is a well-known viral agent with capability of infecting patients undergoing hemodialysis. Liver enzyme levels in infected individuals have been reported to remain within the normal range. Simultaneous infection of GBV-C and other viral agents may occur due to common routes of transmission. A total of 104 hemodialysis patients living in Tehran were included in this case-control study (53 patients with HCV infection, group I; and 51 with no HCV infection, group II). Diagnosis was made by detection Anti-E(2) protein using ELISA and HCV-RNA using RT-PCR. History of HBV-infection, organ transplantation, depression, malignancies, chemotherapy, diabetes mellitus, thyroid disorders and chronic cutaneous disorders were considered. Patients were evaluated for high- risk behaviors such as intravenous drug injection, addiction or substance abuse. A total of 14 patients (13.6%) were GBV-C-infected. Four of them were co-infected with HCV. All patients with GBV-C infection had viral genotype 2. Thirteen patients (12%) had a history of multiple blood transfusions. Mean (+/-SD) age of GBV-C-infected patients was 48.7+/-13.8 years. Among GBV-C infected patients, three patients had a history of organ transplantation and three had a co-morbidity of diabetes mellitus. This study as the first case-control study to evaluate the association between GBV-C and HCV infection, to our knowledge, shows hemodialysis patients living in Tehran are infected with GBV-C with intermediate level of frequency. The association of GBV-C transmission with other viral blood-borne agents might be necessary.     

GB virus C (GBV-C) infection in patients with chronic hepatitis C. Influence on liver disease and on hepatitis virus behaviour: Effect of interferon alfa therapy

The aim of this study was to evaluate, in patients with chronic hepatitis C, 1) the prevalence and the epidemiological characteristics of GB virus C (GBV-C) infection, 2) the influence of GBV-C on hepatitis C virus (HCV) infection, 3) the pathogenicity of GBV-C in the absence of treatment and under interferon therapy, and 4) the effect of interferon alfa on GBV-C and HCV replications. One hundred fifteen patients with chronic hepatitis C were studied. Before treatment, they were tested for GBV-C RNA by PCR and GBV-C genotype was determined for positive samples. Pretreatment information was collected, including age, gender, source of HCV, estimated duration of HCV infection, alanine aminotransferase and gamma-glutamyl transpeptidase activities, cirrhosis and Knodell's score on liver biopsy, HCV genotype, HCV viral burden and anti-HCV core IgM antibodies. The genetic complexity of the hypervariable region 1 (HVR1) of HCV was studied by PCR-Single Strand Conformation Polymorphism. All patients were treated with 3 to 9 mega units of interferon alfa-2a three times per week for 3 to 6 months. The influence of GBV-C on the evolution of ALT and HCV replication during and after treatment was studied, and GBV-C and HCV RNA were monitored monthly by PCR during this period. Eighteen patients (16%) were GBV-C RNA-positive. Among 11 samples studied, GBV-C genotype 2a was present in 9 cases, 2b in one case and type 3 in one case. GBV-C RNA-positive patients were significantly younger than GBV-C RNA-negative ones (38.4 ± 11.5 vs. 47.4 ± 14.0, P = 0.012), a result independent of the route of transmission and the disease duration. No difference between GBV-C RNA-positive and -negative patients was found for other epidemiological parameters (e.g. gender, risk factor for parenteral viral infections, disease duration and HCV genotypes), or for the characteristics of HCV infection and related liver disease (e.g. HCV RNA level, genetic complexity of the HVR1, anti-HCV core IgM, alanine aminotransferase and gamma-glutamyl transpeptidase activities, cirrhosis and Knodell's score). GBV-C did not influence the rates of ALT normalization at months 3, 6 and 12 and of sustained hepatitis C virological response at month 12 of treatment follow-up. During treatment, GBV-C viremia became undetectable in 12 patients (67%) but relapse occurred after treatment withdrawal in all the nine patients with sufficient follow-up. In the remaining six patients (33%), GBV-C resisted interferon. Whatever the effect of interferon on GBV-C replication, the ALT levels correlated with the presence of HCV RNA. In conclusion, GBV-C infection is frequent in patients with chronic hepatitis C, who are mainly, but not exclusively, infected by GBV-C genotype 2a. GBV-C positive patients are significantly younger than GBV-C negative ones. GBV-C does not seem to affect HCV replication, liver disease and responses of HCV infection and liver disease to interferon therapy. GBV-C is sensitive to 3 mega units of interferon alfa administered three times per week in two-thirds of the patients, but relapse is constant with this dosage after treatment withdrawal. J. Med. Virol. 54:26–37, 1998. © 1998 Wiley-Liss, Inc.     

Distribution of hepatitis C virus genotypes among hemodialysis patients in Tehran--a multicenter study

Hepatitis C virus has substantial heterogeneity of genotypes throughout the world. The aim of this study was to determine the frequency of HCV genotypes, risk factors and clinical implications in cases of hemodialysis living in Tehran. A total of 155 patients treated by hemodialysis, who had been identified to be anti-HCV positive at 45 medical centers in Tehran, were enrolled. Genotyping was using restriction fragment length polymorphism (RFLP) on HCV-RNA positive samples. HCV-RNA was detected in 66 (42.6%) patients. Genotyping of HCV-RNA positive serum samples demonstrated that subtypes 3a and 1a were predominant accounting for 30.3 and 28.8%, respectively. The distribution of other HCV genotypes showed genotype 1b, 18.2%; genotype 4, 16.7%; mixed genotypes 1a and 1b, 3%; and genotype 3b, 3%. Genotype 2 was not detected in this study. Statistically significant differences were identified between HCV infected and non-HCV infected patients regarding history of hemodialysis unit changes more than two times (P = 0.01), and history of hemodialysis for more than 20 years (P = 0.02). However, blood transfusion, mean duration of hemodialysis therapy and the history of solid organ transplantation did not differ between these two groups. This study indicates that the dominant HCV genotypes among patients treated by hemodialysis living in Tehran were 3a and 1a, and considering previous reports from the general population, genotype 4 was strongly associated with hemodialysis. The duration of treatment by hemodialysis and, in turn, more hemodialysis unit changes will lead to more frequent HCV infections.     

Molecular epidemiology of hepatitis C virus infection amongst intravenous drug users in rural communities

The prevalence of hepatitis C virus (HCV) infection amongst a group of intravenous drug users (IVDUs) resident in West Suffolk (East Anglia, England) was investigated and compared with the prevalence of infection with hepatitis B virus (HBV) and human immunodeficiency virus (HIV). In addition, both the level of HCV persistence, as defined by detection of viral RNA, and the HCV genotypes present in this population were determined. It was found that HCV antibodies were present in 59% of those tested; by comparison 22% had antibodies to HBV and 1% antibodies to HIV. HCV RNA was found in 44% of those with HCV antibody. HCV genotype 1 was the most prevalent within this population although both genotypes 2 and 3 were also represented. © 1995 Wiley-Liss, Inc.     

Transmission of hepatitis C virus among spouses in Cameroon and the Central African Republic

Heterosexual transmission of hepatitis C virus (HCV) is uncommon, with few studies undertaken in Central Africa. To determine the frequency of inter‐spouse HCV transmission, cross‐sectional studies of elderly individuals in Ebolowa, Cameroon and Nola, Central African Republic, in which, respectively, 24 and 83 long‐term couples had been identified, were examined further. Blood samples were tested for antibody to HCV. Anti‐HCV positive samples were genotyped by phylogenetic analysis of a fragment of the NS5B gene. In Nola, 4 out of 9 (44.4%) wives of anti‐HCV positive husbands and 1 out of 74 (1.4%) wives of anti‐HCV negative husbands were anti‐HCV positive (P < 0.001); in Ebolowa, the corresponding proportions were 10 out of 15 (66.7%) and 3 out of 9 (33.3%) (P = 0.21). After adjustment for age and site‐specific risk factors of HCV infection, HCV seropositivity of the wives remained associated with their husbands' HCV serostatus, significantly so in Nola (P = 0.003) and marginally in Ebolowa (P = 0.06). In 7 out of 14 concordant seropositive couples, the genotype could be determined in both spouses. Four couples were infected with different genotypes, while three were infected with the same genotype. Thus, serological concordance between the spouses was related to a combination of infections acquired independently and inter‐spouse transmission. It could not be determined whether inter‐spouse transmission occurred sexually, through blood–blood contact, or otherwise. Inter‐spouse transmission may have contributed to the high prevalence among elderly populations of Central Africa since some patients infected during healthcare subsequently transmitted the virus to their spouse. J. Med. Virol. 83:2113–2118, 2011. © 2011 Wiley Periodicals, Inc.     

Long-term follow-up of hepatitis B virus and hepatitis C virus replicative levels in chronic hepatitis patients coinfected with both viruses

Dual infection with hepatitis B and C viruses is often encountered in endemic areas of both viruses. However, understanding of the clinical and virological implications is limited. The aim of this study was to investigate the role of each virus in liver injury and the interaction between the two viruses in dual infection with hepatitis B and C viruses. Three patients who had chronic infection with both hepatitis B and C viruses were examined, and a longitudinal study of both serum hepatitis B virus DNA and hepatitis C virus RNA levels over 4 years was undertaken. The results were correlated with serum alanine aminotransferase levels. Serum alanine aminotransferase values showed a relationship with hepatitis B virus replicative levels, but not with hepatitis C virus replicative levels in all 3 patients. Serial changes of replicative levels of both viruses were studied, and it was found that hepatitis C virus replicative levels were enhanced after the decline of hepatitis B virus replication in 1 of the 3 patients. In the remaining 2 patients, a transient rise of hepatitis C virus replicative levels in association with a decrease of hepatitis B virus replication was also observed during part of the follow-up period. These findings indicate that hepatitis B virus may play a dominant etiological role in liver injury, and that a suppressive action between hepatitis B and C viruses may occur in dual infection with both viruses. © 1995 Wiley-Liss, Inc.     

Autoimmune forms of chronic hepatitis associated with hepatitis C virus (HCV) infection with and without HCV-RNA: histological differences from pure autoimmune hepatitis and chronic hepatitis C

Liver biopsy specimens of pure autoimmune hepatitis (pAIH), autoimmune forms of chronic hepatitis with positivity for anti-hepatitis C virus (anti-HCV) and negativity for HCV-RNA (cAIH-RNA(-)), autoimmune forms of chronic hepatitis with positivity for anti-HCV and HCV-RNA (cAIH-RNA(+)), and chronic hepatitis C (CHC) were compared histologically and statistically to clarify the histological character of the autoimmune form of chronic hepatitis with HCV infection. The following representative histological features were used to investigate: inflammation, fibrosis, plasma cell infiltration, lymphoid aggregates/follicles, non-suppurative destructive cholangitis, and the shape of the enlarged portal tracts. While a considerable overlap in histological features between the pAIH and cAIH-RNA(-) groups and between the CHC and cAIH-RNA(+) groups was recognized, the overlap between the pAIH and CHC groups was small. Significant differences were found between cAIH-RNA(-) and cAIH-RAN(+) groups, especially in necroinflammatory findings. In conclusion, most cases of cAIH-RNA(-) with histological features similar to those of pAIH were shown to be AIH. The remaining cases might be CHC with subsidence of viral duplication. Conversely, many cases of cAIH-RNA(+) with histological findings similar to those of CHC were shown to be CHC clinically mimicking pAIH. The remaining cases might represent coexistence of pAIH and HCV infection.     

Effect of interferon on GB virus C and hepatitis C virus in hepatitis patients with the co-infection

Of 74 patients who were infected with hepatitis C virus (HCV) and received interferon, 12 (16%) were positive for RNA of GB virus C (GBV-C). RNA of GBV-C was determined in sera from the co-infected patients retrospectively, and the effect of interferon on GBV-C was compared with that on HCV in them. Titers of both GBV-C and HCV RNAs decreased during interferon in all of them. Two patients lost both GBV-C and HCV RNAs and remained clear until 6 months after treatment with interferon, while 2 lost RNA for GBV-C only and 2 for HCV RNA alone. Low pre-treatment RNA titers of GBV-C and HCV correlated with the efficacy of interferon in clearing. Alanine aminotransferase returned to normal only in the patients who lost HCV RNA, regardless of the persistence or loss GBV-C RNA. These results indicate that the response to interferon of GBV-C is comparable to but independent of that of HCV and that the persistence of GBV-C would not prevent the normalization of aminotransferases in response to interferon in patients with chronic hepatitis C. J. Med. Virol. 52:156–160, 1997. © 1997 Wiley-Liss, Inc.     

Concurrent hepatitis C virus and hepatitis delta virus superinfection in patients with chronic hepatitis B virus infection.

Since hepatitis C virus (HCV) and hepatitis delta virus (HDV) are transmitted by the same routes as hepatitis B virus (HBV), simultaneous or concurrent HCV and HDV infection in patients with chronic HBV infection may occur. To test this hypothesis and to examine the clinicohistological and immunopathological presentations of such multiple hepatitis virus infections, acute and/or convalescent serum specimens from 86 patients with acute HDV superinfection were tested by enzyme immunoassay for antibodies to HCV. Of the 86 patients, 18 (20.9%) were associated with HCV infection. Although patients with early mortality cannot be evaluated by the HCV markers used in this study, the results showed that the clinical and histologic features were similar except that patients with HCV infection were older than those without HCV infection (P less than 0.01). Immunopathological studies carried out within 2 months after the onset of acute HDV superinfection demonstrated that hepatitis B core antigen (HBcAg) was not detected in any patient and HDV antigen was detected in 18.2% of the patients with HCV infection whereas HBcAg and HDAg were found in 7% and 65.1%, respectively, of those without HCV coinfection (P less than 0.02). It is concluded that concurrent HCV and HDV superinfections can and do occur in patients with chronic HBV infection. In these triple viral infections, HCV may even transiently suppress HDV and HBV.     

Hepatitis C virus genotype distribution in China: predominance of closely related subtype 1b isolates and existence of new genotype 6 variants

To determine hepatitis C virus (HCV) genotype distribution in China, a total of 148 HCV RNA positive serum samples were collected from nine geographic areas and subjected to RT-PCR followed by direct DNA sequencing and phylogenetic analysis of the core, E1, and NS5B regions. HCV was genotyped in 139 (93.9%) samples. Among them subtype 1b was the most predominant [66% (92/139)] followed by 2a [14% (19/139)]. Of 92 subtype 1b isolates, 35 (38%) and 30 (33%) formed two clusters, designated groups A and B. Group A was prevalent throughout China, while group B was predominant in the central and southern regions. In three cities in the Pearl River Delta, subtype 6a replaced 2a as the second most predominant subtype, and in Kunming (southwest) multiple HCV genotypes/subtypes were present. New variants of HCV genotype 6 were discovered in three samples from Kunming and one in Guangzhou in the Pearl River Delta.     

Interferon therapy in chronic hepatitis C virus: Evidence of different outcome with respect to different viral strains

The aim of the study was to assess the role of different viral strains of hepatitis C virus (HCV) in determining the outcome of the alpha-interferon (IFN) therapy. Fifty-seven patients (34 from Italy and 23 from Japan) with HCV-positive liver disease were enrolled in the study. The NS4 region of HCV was amplified in sera by “nested” polymerase chain reaction (PCR) using a primer pair synthesized according to the sequence of JK-1. The NS4 region was positive in 14 (41%) Italian and in 13 (56%) Japanese patients. In positive patients the sequence of the NS4 region was also obtained. Subsequently, HCV genotype was determined in all patients by PCR amplification of the core region. All patients received recombinant alpha2a-interferon (IFN), 6 million units 3 times a week for 1 month followed by 3 million units 3 times a week for 5 months. The patients were followed for 1 year after the end of treatment. At the end of the follow-up, 17 (30%) had sustained normal levels of serum alanine aminotransferase (ALT). The outcome of treatment was not correlated with race, age, sex, histology, and pretreatment ALT level, but was significantly (P < 0.00001) associated with the presence of both the NS4-JK-1 region and HCV type II. Among the 27 NS4-positive patients, only 1 patient (3.7%) achieved a complete response, whereas the remaining 26 patients (96.3%) either were non-responders or relapsed after IFN was discontinued. In contrast, among the 30 NS4-JK-1-negative patients, 15 (53%) had a sustained remission. HCV genotyping showed type I in 3 (6%), type II in 40 (74%), type III in 4 (7%), and type IV in 3 (6%) cases. Coinfection was present in 4 (7%), while in 3 cases amplification was not obtained. Patients with type II were all non-responders or relapsers, while a response to the treatment was oberved in 17 of 17 (100%) of the remaining patients. These data indicate that the presence of JK-1 variant of HCV or HCV type II is almost always predictive of a poor response rate Of IFN therapy. © 1995 Wiley-Liss, Inc.     

Impact of universal vaccination on intrafamilial transmission of hepatitis B virus

To control hepatitis B virus (HBV) infection, a nationwide vaccination program was launched in 1984 and resulted in a significant reduction in the rate of persistent infection of children. However, the relative contribution of vaccination to the intrafamilial clustering of HBV infection remains unclear. The rate of intrafamilial HBV transmission in vaccinated children was investigated. Eighty-four sera from vaccinated children were enrolled and HBV serum markers were determined. The modes of intrafamilial HBV transmission were investigated by history taking and serological assay, and confirmed by genotyping and phylogenetic analysis. The results showed 66 (78.6%) vaccinated children born to hepatitis B surface antigen (HBsAg)-negative parents were HBsAg-negative. Eighteen vaccinees were born to HBsAg-positive parents; four (21.4%) of the children were HBsAg-positive. According to the parents' HBsAg status, three patterns of HBsAg-positive parents were identified. Serological analysis showed that three of 15 children born to HBsAg-positive mother (pattern I) and one of two children born to HBsAg-positive father became infected (pattern II). The remaining one child was HBsAg negative with both parents positive for HBsAg (pattern III). Genotyping and phyogenetic analysis confirmed the mode of intrafamilial transmissions. Sequence analysis of S and pre-S genes showed that HBV isolates of HBsAg-positive vaccinees were variants; no G145R but G145A and other substitutions were found. In conclusion, this small study showed that both maternal and paternal transmissions are important of the intrafamilial spread of HBV infection. In addition, the introduction of HBV vaccination has resulted in a reduction of intrafamilial transmission, but a study of a large population is needed.