Chronic hepatitis C infection: influence of the viral load, genotypes, and GBV-C/HGV coinfection on the severity of the disease in a Brazilian population

Pegivirus Detection in Cerebrospinal Fluid from Patients with Central Nervous System Infections of Unknown Etiology in Brazil by Viral Metagenomics

Metagenomic next-generation sequencing (mNGS) methodology serves as an excellent supplement in cases where diagnosis is challenging to establish through conventional laboratory tests, and its usage is increasingly prevalent. Examining the causes of infectious diseases in the central nervous system (CNS) is vital for understanding their spread, managing outbreaks, and effective patient care. In a study conducted in the state of São Paulo, Brazil, cerebrospinal fluid (CSF) samples from 500 patients with CNS diseases of indeterminate etiology, collected between 2017 and 2021, were analyzed. Employing a mNGS approach, we obtained the complete coding sequence of Pegivirus hominis (HPgV) genotype 2 in a sample from a patient with encephalitis (named IAL-425/BRA/SP/2019); no other pathogen was detected. Subsequently, to determine the extent of this virus's presence, both polymerase chain reaction (PCR) and/or real-time PCR assays were utilized on the entire collection. The presence of the virus was identified in 4.0% of the samples analyzed. This research constitutes the first report of HPgV detection in CSF samples in South America. Analysis of the IAL-425 genome (9107 nt) revealed a 90% nucleotide identity with HPgV strains from various countries. Evolutionary analyses suggest that HPgV is both endemic and extensively distributed. The direct involvement of HPgV in CNS infections in these patients remains uncertain.

Hepatitis C and Human Pegivirus Coinfection in Patients with Chronic Hepatitis C from the Brazilian Amazon Region: Prevalence, Genotypes and Clinical Data

Coinfection of HPgV-1 with hepatitis C virus (HCV) is common due to shared modes of transmission, with a prevalence of HPgV-1 viremia of approximately 20% among individuals with chronic HCV infection. The aim of the present study was to estimate the prevalence of HPgV-1 RNA and circulating genotypes in patients with hepatitis C from a health service located in the city of Belém, in the state of Pará, Northern Brazil. A total of 147 samples were included in the study from February to December 2019. Among the participants, 72.1% (106/147) were monoinfected with HCV, with detectable HCV viral RNA, and 27.9% (41/147) were coinfected with HCV/HPgV-1. The most frequently found genotypes were HPgV-1 genotypes 1 and 2 (36.6% and 63.4%), respectively. While for HCV there was a predominance of genotypes 1 and 3 (58.5% and 41.5%). No significant differences were found when comparing any risk, sociodemographic, or clinical factors between groups. Also, there was no statistically significant difference when relating the viral genotypes of both agents. This study indicated that the prevalence of infection by HPgV-1 is high in HCV carriers in Belém, Pará, and probably does not change the clinical course of HCV infection, however, further studies are still needed.

Intrahepatic TLR3 and IFNL3 Expressions Are Associated with Stages of Fibrosis in Chronic Hepatitis C

An inefficient immune response against the hepatitis C virus (HCV), combined with viral evasion mechanisms, is responsible for the chronicity of infection. The need to evaluate the innate mechanisms of the immune response, such as TLR3 and IFN-λ3, and their relationship with the virus-host interaction is important for understanding the pathogenesis of chronic hepatitis C. The present study aimed to investigate the gene expressions of TRL3 and IFNL3 in liver tissue, seeking to evaluate whether these could be potential biomarkers of HCV infection. A total of 23 liver biopsy samples were collected from patients with chronic HCV, and 8 biopsies were collected from healthy control patients. RNA extraction, reverse transcription and qPCR were performed to quantify the relative gene expressions of TLR3 and IFNL3. Data on the viral load; AST, ALT, GGT and AFP levels; and the viral genotype were collected from the patients' medical records. The intrahepatic expression of TLR3 (p = 0.0326) was higher in chronic HCV carriers than in the control group, and the expression of IFNL3 (p = 0.0037) was lower in chronic HCV carriers than in the healthy control group. The expression levels of TLR3 (p = 0.0030) and IFNL3 (p = 0.0036) were higher in the early stages of fibrosis and of necroinflammatory activity in the liver; in contrast, TLR3 and IFNL3 expressions were lower in the more advanced stages of fibrosis and inflammation. There was no correlation between the gene expression and the serum viral load. Regarding the initial METAVIR scale scores, liver transaminase levels were lower in patients with advanced fibrosis when correlated with TLR3 and IFNL3 gene expressions. The results suggest that in the early stages of the development of hepatic fibrosis, TLR3 and IFN-λ3 play important roles in the antiviral response and in the modulation of the tolerogenic liver environment because there is a decrease in the intrahepatic expressions of TLR3 and IFNL3 in the advanced stages of fibrosis, probably due to viral evasion mechanisms.

Hepatitis C virus genotypes and associated risk factors in the state of Pará, Northern Brazil

Background

Despite the emergence of more effective therapies, hepatitis C virus (HCV) infection remains a serious public health problem at the global level. Currently, this virus is classified into seven genotypes and 67 subgenotypes, which in turn are distributed heterogeneously in Brazil and worldwide. Studies have shown that this genetic divergence results in differences in the progression of chronic disease associated with HCV infection and its treatment.

Objective

The aim of this study was to report the frequency of HCV genotypes in the state of Pará, Northern Brazil, and to assess the association between genotype and different clinical and laboratory characteristics, as well as risk factors for infection.

Method

Data from 85 medical records of untreated patients who had chronic hepatitis C infection were analyzed; the patients were evaluated at two hospitals in Belem, Pará, Brazil.

Results

Circulation of genotypes 1 and 3 was detected, with a higher prevalence of genotype 1 (75.3%) than genotype 3 (24.7%). In addition, there was a predominance of subgenotype 1b (60.34%) compared to 1a (20.69%) and 3a (18.97%). Reuse of needles and/or glass syringes was significantly associated with infection by HCV genotype 1 than genotype 3; however, the small number of patients infected with genotype 3 may have biased the results. No associations between genotype and the evaluated clinical and laboratory characteristics were observed.

Conclusion

This study reinforces the differences in the distribution of HCV genotypes in Brazil and showed no association between HCV genotype and progression of chronic hepatitis C in the studied group.

Genotype Distribution and Prevalence of Human Pegivirus among High-Risk Populations in Tunisia

OBJECTIVE

A recently discovered non-A-E hepatitis virus has been designated as human Pegivirus (HPgV). HPgV is prevalent in high-risk groups such as patients with hepatitis C virus (HCV), and it is of interest for patients who are at risk for transmitted infections. The aim of this study was to evaluate the prevalence of HPgV as well as the genotype distribution among patients in the Tunisian population who are infected with HCV and also in multitransfused patients.

METHODS

A total of 144 patients were screened using RTPCR/nested PCR of the 5'-untranslated region (UTR); 14 cases were sequenced and phylogenetically analyzed.

RESULTS

Seven (14.9%) subjects from the multitransfused group and 7 (7.2%) patients infected with HCV, respectively, were found positive for HPgV RNA. Sequencing and phylogenetic analysis of the 14 cases revealed that genotype 2a was the main genotype circulating in Tunisian patients. Genotype 2b was found in the amplified samples of 2 HCV-infected patients.

CONCLUSION

This study enriches the limited data on HPgV prevalence in Tunisia, and shows, for the first time, the molecular epidemiology of the circulating strains in this country.

Clinical Profile and Response to Treatment with Pegylated Interferon α 2b and Ribavirin in Chronic Hepatitis C-A Reappraisal from a Tertiary Care Center in Northern India

AIM

To assess the clinical profile of 80 chronic hepatitis C patients in a tertiary health care center in Northern India and also to study the efficacy and tolerability of pegylated interferon (Peg-IFN) α 2b and ribavirin therapy in a cohort of chronic hepatitis C patients.

METHODS

Thirty subjects with chronic hepatitis C (CH-C) with genotypes 2 and 3 received Peg-IFN α 2b 1.5 μg/kg subcutaneously weekly plus daily ribavirin 800 mg for 24 weeks .Subjects with genotype 1 infection received therapy for 48 weeks with ribavirin 1000 mg/day and Peg-IFN α 2b dose remained the same. The primary end point was the sustained viral response (SVR). Drug dosage was modified or temporarily discontinued if anemia or bone marrow suppression developed.

RESULTS

The clinical profile of chronic hepatitis C infected patients showed decompensated cirrhosis in the more elderly patients. Genotype 3 was the commonest genotype and was seen in 21 (70%) patients. The mean baseline HCV RNA was high. SVR was achieved less commonly with genotype 1 than with genotype 2/3. Patients who became negative for HCV RNA at 4-weeks (rapid virological response or RVR) and 12 weeks (early virological response or EVR) of treatment showed significantly higher sustained virological response (SVR) rates. Similarly, patients who showed normalization of ALT level at 4-weeks and 12-weeks of treatment showed significant high rate of SVR. Overall treatment was well tolerated.

CONCLUSION

In our region, CHC subjects have high viral load and genotype 3 being the most common. Treatment with Peg-IFN α 2b and ribavirin is effective and well tolerated. Genotype 1 was more resistant to the treatment. Patients who achieved RVR and EVR are more likely to achieve SVR. Although the numbers of patients in this study was small, considering the paucity of data of treatment from India, the data is relevant.

GB Virus C infection in Patients With HIV/Hepatitis C Virus Coinfection: Improvement of the Liver Function in Chronic Hepatitis C

BACKGROUND

Previous studies in patients with hepatitis C virus (HCV)/HIV coinfection have shown that the presence of GBV-C is associated with significantly less compensated and decompensated cirrhosis, and an improvement in cirrhosis-free survival.

OBJECTIVES

This study aimed to describe the effect of GBV-C in patients with chronic hepatitis C and HIV coinfection.

PATIENTS AND METHODS

We retrospectively studied 105 injecting drug users with chronic hepatitis C and HIV coinfection and 72 patients with chronic HCV mono-infections. Plasma samples were tested for GBV-C RNA with primers to the 5'untranslated region gene. HIV and HCV viral load, CD4(+) and CD8(+) cell count, and the levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were tested in all patients.

RESULTS

GBV-C RNA was identified in 34 (32.38%) of the patients with HIV/HCV coinfection, and in 24 (33.33%) of the patients with HCV mono-infection. GBV-C infection was associated with significantly lower ALT and AST levels in patients with chronic hepatitis C and HIV coinfection, but not in those HCV mono-infections. The presence of GBV-C infection was not correlated with CD4(+) and CD8(+) cell count, gender, age, HIV load, HCV load, and HCV genotype.

CONCLUSIONS

This study found that GBV-C infection has a high frequency among injecting drug users with HIV/HCV coinfection and HCV mono-infection in Yunnan, China. In patients with chronic hepatitis C and HIV coinfection, GBV-C RNA was associated with significantly lower ALT and AST levels, suggesting a beneficial effect of GBV-C infection on chronic hepatitis C.

Role of nitric oxide synthase genes in hepatitis E virus infection

Hepatitis E virus (HEV) is the most common cause of endemic and epidemic acute hepatitis. A correlation between iNOS, eNOS polymorphisms, levels and severity of disease has been reported, and here, we examined the role of iNOS and eNOS gene polymorphisms and their levels in HEV-related acute viral hepatitis and acute liver failure. Hepatitis E virus-related cases of acute hepatitis (294 patients) and liver failure (82 patients) and age- and sex-matched healthy controls (331 subjects) were included in the study. PCR-RFLP was performed to identify the polymorphisms in the iNOS and eNOS genes. iNOS and eNOS levels were studied using ELISA assays and HEV viral load, genotype and combined effects of iNOS genotype, levels and parameters for disease severity were examined. The frequency of iNOS (CT + TT) and eNOS (GT + TT) genotypes was higher in subjects with liver failure compared with controls. iNOS and eNOS levels in patients with acute liver failure (55.51 ± 6.33 IU/mL, 60.2 ± 3.69) cases were significantly increased as compared to patients with acute viral hepatitis (17.8 ± 6.08 IU/mL, 23.7 ± 6.57) and controls (P < 0.05). A significant positive correlation was observed between the iNOS and eNOS levels in our study population when compared with the severity of disease parameters. Hence, the iNOS C150T polymorphism and the eNOS G894T polymorphism and high levels of iNOS and eNOS are associated with an increased risk of HEV-related acute hepatitis and liver failure. This study supports the possible role of nitric oxide synthase genes (iNOS and eNOS) in determining the severity of HEV infection.

Genetic diversity of HCV in Brazil

BACKGROUND

Many studies have documented the molecular epidemiological scenario of HCV within individual Brazilian states, but we still have an incomplete understanding of the dispersion dynamics of the virus in different regions throughout the country.

METHODS

A total of 676 HCV NS5B gene sequences of subtypes 1a (n=321), 1b (n=170) and 3a (n=185), isolated from seven different Brazilian states covering four out of five regions were analysed in the present study. We also analysed 22 HCV NS5B gene sequences of minor genetic variants including genotype 2 (n=13), genotype 4 (n=6) and subtype 5a (n=3). Brazilian HCV sequences were aligned with sequences of non-Brazilian origin and subjected to maximum likelihood phylogenetic analyses.

RESULTS

These analyses revealed that the Brazilian HCV epidemic resulted from multiple introductions and autochthonous transmission of subtypes 1a, 1b, 3a and genotypes 2, 4 and 5. Brazilian HCV subtype 1a epidemic is dominated by the dissemination of one major clade; while Brazilian HCV subtypes 1b and 3a epidemics are characterized by concurrent dissemination of several independent HCV lineages. Some HCV Brazilian lineages of subtypes 1a, 1b, 2b and 3a were successful in becoming established and disseminated through several regions in the country. Despite significant phylogenetic intermixing of Brazilian sequences, the distribution of HCV strains from different states across lineages was not completely homogeneous.

CONCLUSIONS

These results demonstrate the existence of multiple introductions and local propagation of both prevalent and uncommon HCV genetic variants in Brazil and identify some major Brazilian HCV clades with nationwide dissemination. This study also suggests that the observed HCV diversity in Brazil has been shaped by both frequent viral migration among regions and in situ viral dissemination.

Dynamics of resistance mutations to NS3 protease inhibitors in a cohort of Brazilian patients chronically infected with hepatitis C virus (genotype 1) treated with pegylated interferon and ribavirin: a prospective longitudinal study

Abstract

About sixty thousand new cases of Hepatitis C virus (HCV) infection are recorded in Brazil each year. These cases are currently treated with pegylated interferon (PEG-IFN) and ribavirin (RBV) with an overall success rate of 50%. New compounds for anti-HCV therapy targeted to the HCV NS3 protease are being developed and some already form the components of licensed therapies. Mapping NS3 protease resistance mutations to protease inhibitors or anti-viral drug candidates is important to direct anti-HCV drug treatment.

Methods

Sequence analysis of the HCV NS3 protease was conducted in a group of 68 chronically infected patients harboring the HCV genotype 1. The patients were sampled before, during and after a course of PEG-IFN-RBV treatment.

Results

Resistance mutations to the protease inhibitors, Boceprevir and Telaprevir were identified in HCV isolated from three patients (4.4%); the viral sequences contained at least one of the following mutations: V36L, T54S and V55A. In one sustained virological responder, the T54S mutation appeared during the course of PEG-IFN and RBV therapy. In contrast, V36L and V55A mutations were identified in virus isolated from one relapsing patient before, during, and after treatment, whereas the T54S mutation was identified in virus isolated from one non-responding patient, before and during the treatment course.

Conclusions

The incidence and persistence of protease resistance mutations occurring in HCV from chronically infected patients in Brazil should be considered when using protease inhibitors to treat HCV disease. In addition, patients treated with the current therapy (PEG-IFN and RBV) that are relapsing or are non-responders should be considered candidates for protease inhibitor therapy.

Does high viral load of hepatitis E virus influence the severity and prognosis of acute liver failure during pregnancy?

The incidence and mortality in pregnant women with acute liver failure caused by hepatitis E virus (HEV) is high. Data on the viral load of HEV during pregnancy are limited. The study was designed to determine the viral load of HEV and its association with the disease severity in patients with acute liver failure. A total of HEV related 163 patients with acute liver failure which included 105 pregnant, 46 non-pregnant women and girls and 12 men and 730 patients with acute viral hepatitis which comprised of 220 pregnant women; 282 non-pregnant women and girls and 228 men were included. Viral load was measured by real-time PCR. Comparison was made between the pregnant and non-pregnant women. HEV RNA was detectable in 265 patients (142 pregnant; 75 non-pregnant and 48 men) and 104 patients with acute liver failure (64 pregnant, 34 non-pregnant and 6 men). The viral load of HEV in pregnant women with acute liver failure and acute viral hepatitis was significantly higher 129,984.0 ± 103,104.17 and 768.92 ± 1,105.40 copies/ml, respectively compared to the non-pregnant women which was 189.2 ± 225 and 12.73 ± 7.8 copies/ml (P < 0.0001). The viral load of HEV was also significantly higher in the pregnant patients with acute liver failure compared to the pregnant women with acute viral hepatitis and also men (P < 0.0001). High viral load of HEV during pregnancy could be one of the factors responsible for the severity of the infection during pregnancy.

Role of GB virus C in modulating HIV disease

GB virus C (GBV-C) is a member of the Flaviviridae family and the most closely related human virus to HCV. However, GBV-C does not replicate in hepatocytes, but rather in lymphocytes. GBV-C has a worldwide distribution and is transmitted sexually, parenterally and through mother-to-child transmission. Thus, co-infection with HCV and HIV is common. Until now, no human disease has been associated with GBV-C infection. However, there are several reports of a beneficial effect of GBV-C on HIV disease progression in vivo. Different mechanisms to explain these observations have been proposed, including modification of antiviral cytokine production, HIV co-receptor expression, direct inhibition of HIV-1 entry, T-cell activation and Fas-mediated apoptosis. Further understanding of these mechanisms may open new strategies for the treatment of HIV/AIDS.

Prevalence, incidence density, and genotype distribution of GB virus C infection in a cohort of recently HIV-1-infected subjects in Sao Paulo, Brazil

BACKGROUND

The results of previous studies elsewhere have indicated that GB virus C (GBV-C) infection is frequent in patients infected with the human immunodeficiency virus type 1 (HIV-1) due to similar transmission routes of both viruses. The aim of this study was to determine the prevalence, incidence density and genotypic characteristics of GBV-C in this population.

METHODOLOGY/PRINCIPAL FINDINGS

The study population included 233 patients from a cohort primarily comprised of homosexual men recently infected with HIV-1 in São Paulo, Brazil. The presence of GBV-C RNA was determined in plasma samples by reverse transcriptase-nested polymerase chain reaction and quantified by real-time PCR. GBV-C genotypes were determined by direct sequencing. HIV viral load, CD4+ T lymphocyte and CD8+ T lymphocyte count were also tested in all patients. The overall prevalence of GBV-C infection was 0.23 (95% CI: 0.18 to 0.29) in the study group. There was no significant difference between patients with and without GBV-C infection and Glycoprotein E2 antibody presence regarding age, sex, HIV-1 viral load, CD4+ and CD8+T cell counts and treatment with antiretroviral drugs. An inverse correlation was observed between GBV-C and HIV-1 loads at enrollment and after one year. Also, a positive but not significant correlation was observed between GBV-C load and CD4+ T lymphocyte. Phylogenetic analysis of the GBV-C isolates revealed the presence of genotype 1 and genotype 2, these sub classified into subtype 2a and 2b.

CONCLUSION/SIGNIFICANCE

GBV-C infection is common in recently HIV -1 infected patients in Sao Paulo, Brazil and the predominant genotype is 2b. This study provides the first report of the GBV-C prevalence at the time of diagnosis of HIV-1 and the incidence density of GBV-C infection in one year.

GB virus C infection among young, HIV-negative injection drug users with and without hepatitis C virus infection

Our study examined the association between GB virus C (GBV-C) and (i) hepatitis C virus (HCV) infection status, (ii) biomedical indicators of liver disease (alanine and aspartate aminotransferases) and (iii) HCV RNA level among young injection drug users (IDUs) recruited using street outreach and respondent-driven methods. Cross-sectional and longitudinal analyses were completed. GBV-C (active or resolved) infection was significantly (P < 0.05) more prevalent among HCV antibody-positive (anti-HCV+) (65.1%) than antibody-negative (anti-HCV-) (32.3%) (OR = 3.9, 95% CI: 2.3-6.9) IDUs. The prevalence of resolved GBV-C infection was highest among those with chronic HCV infection (41.9%), followed by those with resolved HCV infection (34.4%) and significantly lower (P < 0.05) among anti-HCV participants (16.9%). Although not statistically significant (P = 0.13), a similar pattern was observed for active GBV-C infection. No association between GBV-C infection status and biomedical indicators of liver disease or HCV RNA level over time was observed. In conclusion, GBV-C infection prevalence was higher among anti-HCV+ compared to anti-HCV- young IDUs, similar to prior studies among older populations. In particular, chronically HCV-infected young IDUs had an increased rate of GBV-C clearance.

Does hepatitis E viral load and genotypes influence the final outcome of acute liver failure during pregnancy?

BACKGROUND

Hepatitis E is a major health problem in developing countries including India. The incidence and mortality rate in pregnant women with fulminant hepatic failure (FHF) due to hepatitis E virus (HEV) has been reported to be significantly higher, specifically in Asian women. Pregnancy is usually associated with an altered status of sex steroid hormones and immunity. Steroid hormones directly influence the replication through their effects on viral regulatory elements. Moreover, pregnant women in Asia generally suffer from folate deficiency, which is known to cause reduced immunocompetence leading to greater risk of multiple viral infections and higher viral load.

OBJECTIVES

To correlate and analyze the viral load and genotypes of HEV in acute liver failure with that of acute viral hepatitis among pregnant and nonpregnant women.

MATERIALS AND METHODS

A total of 100 FHF and 150 acute viral hepatitis (AVH) patients (50, 75 pregnant and 50, 75 nonpregnant, respectively), were included in the study. These cases were evaluated on the basis of history, clinical examination, liver function profile, and serological test of hepatitis A, B, C, and E using commercially available ELISA kits. Quantification of HEV RNA-positive samples was carried out.

RESULTS

Out of 100 FHF and 150 acute viral hepatitis (AVH) patients, 28 (56%) and 22 (29.3%) pregnant and 7 (14%) and 8 (16%) nonpregnant, respectively, were HEV RNA-positive. HEV viral load in FHF pregnant women was 5.87 x 10(4)+/- 1.5 x 10(5) microL/mL as compared to AVH pregnant women 343.29 +/- 216.44 microL/mL and FHF and AVH nonpregnant 199.2 +/- 225.5 microL/mL and 13.83 +/- 7.8 microL/mL, respectively. Sequencing data of all the positive samples of FHF and AVH pregnant and nonpregnant women showed genotype 1.

CONCLUSION

HEV viral load was found to be significantly higher (P < 0.05) in pregnant patients compared to the nonpregnant. Pregnancy appears to be a risk factor for viral replication. The viral copies of HEV in FHF pregnant women were comparatively higher when compared to AVH pregnant women, which may be related to the severity of the disease in these patients. We could detect only one genotype (genotype 1) in our study population. Thus in the absence of other genotypes in this population, the impact of genotype could not be adequately assessed in this study.

Distribution of hepatitis C virus genotypes among blood donors from mid-west region of Brazil

In order to investigate the hepatitis C virus (HCV) genotypes in mid-west region of Brazil, 250 anti-HCV positive blood donors were studied. Among them, the anti-HCV serological status was confirmed in 205 (82%). HCV RNA was detected in 165 samples, which were genotyped. HCV types 1, 2 and 3 were found in 67.9%, 3% and 29.1% of the donors, respectively. In Goiás state, subtype 1a (50%) was the most prevalent, followed by subtypes 3a (30.9%) and 1b (16.7%). In Mato Grosso state, subtype 1a was also predominant (41%), followed by subtypes 1b (29.5%) and 3a (25%). In Mato Grosso do Sul state, subtypes 1a and 1b were detected equally (36.8%), followed by 3a (21.1%). Subtype 2b was rare (2.4%, 4.5% and 5.3%, respectively). In Distrito Federal, subtype 3a (39%) was more frequent than 1a (31.7%) and the remaining (29.3%) belonged to subtype 1b.

GB virus C: insights into co-infection

GB virus C (GBV-C) is a single stranded positive sense RNA virus, which is a member of the Flaviviridae. It has a close sequence homology and genomic organisation to hepatitis C virus (HCV). However, unlike HCV it is not hepatotrophic. GBV-C replicates within cells of the haemopoietic lineage, in particular lymphocytes. No disease has been associated with GBV-C infection but co-infection with human immunodeficiency virus (HIV) leads to improved morbidity and mortality for the HIV infected individual and slows progression to acquired immunodeficiency syndrome. This potential benefit of GBV-C has been demonstrated in the pre and post highly active anti-retroviral treatment (HAART) eras. GBV-C has been found to decrease HIV replication in in vitro models. The mechanism of the beneficial effect of GBV-C appears to be mediated by alterations in the cellular immune response, the details of which remain unclear. Despite this, there continues to be controversy regarding the influence of GBV-C on HIV as several reports have questioned the beneficial effect. GBV-C does not appear to influence liver related disease in subjects co-infected with HCV or hepatitis B virus (HBV). Combination of HIV and HCV leads to accelerated liver disease. The influence of GBV-C in this situation is yet to be determined. Elucidation of the putative protective effect of GBV-C in HIV co-infection could potentially identify novel targets for anti-HIV therapeutics and lead to the development of disease modifying vaccines.

Treatment of hepatitis C virus infection in patients of northern India

BACKGROUND AND AIM

The purpose of the present study was to evaluate the therapeutic response of north Indian patients with chronic hepatitis C (CH-C) to two different treatment regimens of interferon and ribavirin.

METHODS

Consecutive patients with a diagnosis of CH-C attending the Liver Clinic at the All India Institute of Medical Sciences, New Delhi between April 1999 and April 2002 were included in the study. A competitive reverse transcription-polymerase chain reaction (RT-PCR) method developed in the authors' laboratory was used for quantification of hepatitis C virus (HCV)-RNA. Genotyping of HCV was also determined. The clinical, biochemical, virological and histological parameters were used to assess the therapeutic response among a clinical cohort of patients with chronic hepatitis C. They were treated with two different protocols (interferon [IFN]-alpha-2b, 3 million units daily and ribavirin 10.6 mg/kg daily in two divided doses for 6 months or IFN-alpha-2b, 3 million units thrice weekly and ribavirin 10.6 mg/kg daily for 6 months).

RESULTS

Sixty-five patients with CH-C were included in the study. Blood transfusion (n = 28, 43%) and community-acquired (n = 23, 35%) HCV infections were the commonest. The mean HCV load was high (24.14 +/- 12.5 x 10(8) copies/mL). Genotype 2 and 3 were prevalent in 80% (41/51) of the patients. Forty-five patients received 3 million units of IFN thrice weekly and 20 received the same dose daily. All received the same dose of ribavirin. A sustained virological response (SVR) of 95% (19/20) was achieved among patients receiving daily IFN, whereas 64.4% (29/45) of those who received IFN thrice weekly had SVR. The virological relapse was significantly lower among patients who received daily IFN than in those treated with thrice weekly IFN (n = 1/20, 5% vs 10/39, 25.6%; P = 0.015). The proportion of patients receiving daily IFN among those achieving SVR (19/48, 40%) was significantly higher than the proportion of patients receiving similar therapy among patients without SVR (1/17, 6%; P = 0.02).

CONCLUSIONS

Transfusion and community-acquired HCV infection were the major causes of CH-C. Genotype 2 and 3 HCV were most prevalent among these patients. Despite high viral load, these patients responded well to a combination of daily IFN-alpha-2b and ribavirin.

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.

Non-A to E hepatitis

PURPOSE OF THE REVIEW

The list of possible hepatotropic viruses continues to grow with the discovery of the GB virus-C, the TT virus and the SEN virus. There is emerging data on the biology of these newly discovered :In spite of continuing research into the pathogenicity of the GB virus-C and the TT virus, definite evidence linking them to acute or chronic liver disease is lacking. The SEN virus was reported in 2000, and although there seems to be an association between virus and transfusion-related hepatitis, more data are awaited before definite conclusions can be drawn. The effect of GB virus-C, the TT virus and the SEN virus co-infection on other viral and non-viral hepatitides has also been studied in some detail. Again, there is no definite evidence so far that these viruses modify other liver diseases.

SUMMARY

At the present time, diagnostic testing for these viruses does not seem to be warranted outside of clinical studies. The discovery of these viruses, however, paves the way for further research into novel viral agents that infect humans, other among hosts.