Characterization of seven genotypes (A to E, G and H) of hepatitis B virus recovered from Japanese patients infected with human immunodeficiency virus type 1

TGF-β1/SMAD3-driven GLI2 isoform expression contributes to aggressive phenotypes of hepatocellular carcinoma

Hedgehog signaling is activated in response to liver injury, and modulates organogenesis. However, the role of non-canonical hedgehog activation via TGF-β1/SMAD3 in hepatic carcinogenesis is poorly understood. TGF-β1/SMAD3-mediated non-canonical activation was found in approximately half of GLI2-positive hepatocellular carcinoma (HCC), and two new GLI2 isoforms with transactivating activity were identified. Phospho-SMAD3 interacted with active GLI2 isoforms to transactivate downstream genes in modulation of stemness, epithelial-mesenchymal transition, chemo-resistance and metastasis in poorly-differentiated hepatoma cells. Non-canonical activation of hedgehog signaling was confirmed in a transgenic HBV-associated HCC mouse model. Inhibition of TGF-β/SMAD3 signaling reduced lung metastasis in a mouse in situ hepatic xenograft model. In another cohort of 55 HCC patients, subjects with high GLI2 expression had a shorter disease-free survival than those with low expression. Moreover, co-positivity of GLI2 with SMAD3 was observed in 87.5% of relapsed HCC patients with high GLI2 expression, indicating an increased risk of post-resection recurrence of HCC. The findings underscore that suppressing the non-canonical hedgehog signaling pathway may confer a potential strategy in the treatment of HCC.

Marked reduction in the incidence of transfusion-transmitted hepatitis B virus infection after the introduction of antibody to hepatitis B core antigen and individual donation nucleic acid amplification screening in Japan

BACKGROUND

In Japan, 41 million blood donations have been screened for hepatitis B virus (HBV) during the past 8.4 years using individual donation nucleic acid amplification testing (ID-NAT) and antibody to hepatitis B core antigen (anti-HBc) screening.

STUDY DESIGN AND METHODS

Transfusion-transmitted HBV infection (TT-HBV) incidence was examined. Donated blood implicated in TT-HBV was analyzed for infection stage and DNA levels. Causative HBV strains were phylogenetically analyzed.

RESULTS

Among 5162 (0.013%) ID-NAT positives, window period (WP) and occult HBV infection (OBI) accounted for 3.4% (176) and 11.5% (594), respectively. No OBI-related TT-HBV occurred. Seven blood donations caused eight TT-HBV cases, six of which were in the pre-ID-NAT WP, leaving one with an unresolved infection stage. Seven cases were caused by platelet concentrate (180 mL plasma) and one case by fresh-frozen plasma (200 mL plasma), which contained estimated infectious doses varying between 2 and 2300 HBV virions. HBV subgenotypes in five cases were HBV/A2. Complete genome sequences of the transmitting A2 strains were nearly identical (99.6%-100%) and clustered in a group that included HBV/HIV-1 coinfections and a higher proportion of donors in the acute infection phase (69%) than the other group of HBV/A2 sequences (5%).

DISCUSSION

The incidence of observed TT-HBV cases has significantly reduced to 0.19 per million in the ID-NAT screening period. OBI-related TT-HBV was eliminated by anti-HBc screening. Established TT-HBV cases were caused by blood products with large plasma volumes containing extremely low HBV concentrations derived from blood donors at a very early infection stage.

Rapid quantification assay of hepatitis B virus DNA in human serum and plasma by Fully Automated Genetic Analyzer μTASWako g1

Real-time monitoring of serum hepatitis B virus (HBV) levels is essential for the management of patients with chronic HBV infection in clinical practice, including monitoring the resistance of anti-HBV nucleotide analog or the detection of HBV reactivation. In this context, serum HBV deoxyribonucleic acid (DNA) quantification should be rapidly measured. A rapid HBV DNA quantification assay was established on the Fully Automated Genetic Analyzer, μTASWako g1. The assay performs automated sample preparation and DNA extraction, followed by the amplification and detection of quantitative polymerase chain reaction (PCR) combined with capillary electrophoresis (qPCR-CE) on integrated microfluidic chip. This study aimed to evaluate the analytical and clinical performance of HBV DNA assay on the μTASWako g1 platform in human serum and EDTA-plasma. The HBV DNA assay has a linear quantitative range from 20 to 108 IU/mL of HBV DNA with standard deviation (SD) of ≤0.14 log10 IU/mL. The limits of detection of the assay were 4.18 for the serum and 4.35 for EDTA-plasma. The HBV assay demonstrated the equivalent performance in both human serum and EDTA-plasma matrices. The HBV genotypes A to H were detected with an accuracy of ±0.34 log10 IU/mL. In quantification range, the HBV DNA assay was correlated with Roche cobas AmpliPrep/cobas TaqMan Ver2.0 (CAP/CTM v2) (r = 0.964). The mean difference (μTASWako g1-CAP/CTM v2) of the reported HBV DNA was -0.01 log10 IU/mL. Overall, the sensitivity, accuracy, and precision of the μTASWako g1 HBV assay were comparable to the existing commercial HBV DNA assay, and the assay can be completed within 110 min. This evaluation suggests that the HBV DNA assay on the μTASWako g1 is potentially applied for alternative method of the HBV viral load test, in particular with the advantage of the HBV DNA result availability within 2 h, improving the HBV infection management.

Hepatitis B Virus Genotype G: The Odd Cousin of the Family

With a widespread distribution but low prevalence worldwide, the hepatitis B virus (HBV) genotype G (HBV/G) is a recently described genotype for which the origin and biology are poorly understood. Some unique features make HBV/G the most peculiar of all genotypes. In this review, we reflect on the major milestones in HBV/G research, highlighting the main aspects of its discovery, molecular epidemiology, and virological and clinical characteristics. We also illustrate common pitfalls in the routine detection, which may lead to underestimated rates of HBV/G infection. Large-scale analysis of data from dozens of articles was further performed, with the aim of gaining comprehensive insights into the epidemiological aspects of HBV/G. Finally, we point out recent findings on HBV/G origins and discuss new perspectives regarding the evolutionary history of HBV/G and the plausibility of an African geographic re-emergence of this genotype.

Virologic analysis of tenofovir resistance in a patient with chronic hepatitis B experiencing viral breakthrough during combination treatment with tenofovir disoproxil fumarate and entecavir

Tenofovir disoproxil fumarate (TDF) is widely used to treat hepatitis B virus (HBV) patients worldwide. We previously reported a patient with CHB and cirrhosis in whom viral breakthrough occurred during combination therapy with TDF and entecavir (ETV) against ETV-resistant virus. A recent Korean report showed that two patients with viral breakthrough during treatment with TDF-containing regimens were found to carry five reverse transcriptase (rt) mutations ([rt]S106C[C], rtH126Y[Y], rtD134E[E], rtM204I/V, and rtL269I [I]), with the C, Y, E, and I mutations being associated with tenofovir resistance. We report the clinical course up to September 2019 in our patient, and compare the HBV mutations to those of the two Korean patients. Four mutations (rtS106C, rtD134N/S[N/S], rtM204V, and rtL269I) plus ETV resistance (rtL180M and rtS202G) existed when she developed viral breakthrough during ETV and TDF combination therapy in April 2013. Moreover, three mutations (rtS106C, rtD134N, and rtL269I) existed at baseline. Our patient's father is Korean. Considering these factors, patients with these three or four mutations (CYEI or CN/SI) at baseline could experience tenofovir resistance in addition to lamivudine (LAM) or ETV resistance. In addition, HBV DNA levels fluctuated during tenofovir alafenamide (TAF) and LAM therapy in our patient, although treatment was switched from LAM, TDF, and ETV to LAM and TAF combination therapy in April 2018. In conclusion, three mutations (CN/SI) plus ETV resistance (rtL180M, rtM204V, and rtS202G) can cause tenofovir resistance. Long-term therapy with tenofovir against ETV-resistant virus has the potential to induce viral breakthrough and resistance, necessitating careful follow-up.

Analysis of HBV Genomes Integrated into the Genomes of Human Hepatoma PLC/PRF/5 Cells by HBV Sequence Capture-Based Next-Generation Sequencing

Hepatitis B virus (HBV) infection is a leading cause of hepatocellular carcinoma (HCC) worldwide. The integration of HBV genomic DNA into the host genome occurs randomly, early after infection, and is associated with hepatocarcinogenesis in HBV-infected patients. Therefore, it is important to analyze HBV genome integration. We analyzed HBV genome integration in human hepatoma PLC/PRF/5 cells by HBV sequence capture-based next-generation sequencing (NGS) methods. We confirmed the results by using Sanger sequencing methods. We observed that HBV genotype A is integrated into the genome of PLC/PRF/5 cells. HBV sequence capture-based NGS is useful for the analysis of HBV genome integrants and their locations in the human genome. Among the HBV genome integrants, we performed functional analysis and demonstrated the automatic expression of some HBV proteins encoded by HBV integrants from chromosomes 3 and 11 in Huh7 cells transfected with these DNA sequences. HBV sequence capture-based NGS may be a useful tool for the assessment of HBV genome integration into the human genome in clinical samples and suggests new strategies for hepatocarcinogenesis in HBV infection.

Prevalence and burden of HBV co-infection among people living with HIV: A global systematic review and meta-analysis

Globally, in 2017 35 million people were living with HIV (PLHIV) and 257 million had chronic HBV infection (HBsAg positive). The extent of HIV-HBsAg co-infection is unknown. We undertook a systematic review to estimate the global burden of HBsAg co-infection in PLHIV. We searched MEDLINE, Embase and other databases for published studies (2002-2018) measuring prevalence of HBsAg among PLHIV. The review was registered with PROSPERO (#CRD42019123388). Populations were categorized by HIV-exposure category. The global burden of co-infection was estimated by applying regional co-infection prevalence estimates to UNAIDS estimates of PLHIV. We conducted a meta-analysis to estimate the odds of HBsAg among PLHIV compared to HIV-negative individuals. We identified 506 estimates (475 studies) of HIV-HBsAg co-infection prevalence from 80/195 (41.0%) countries. Globally, the prevalence of HIV-HBsAg co-infection is 7.6% (IQR 5.6%-12.1%) in PLHIV, or 2.7 million HIV-HBsAg co-infections (IQR 2.0-4.2). The greatest burden (69% of cases; 1.9 million) is in sub-Saharan Africa. Globally, there was little difference in prevalence of HIV-HBsAg co-infection by population group (approximately 6%-7%), but it was slightly higher among people who inject drugs (11.8% IQR 6.0%-16.9%). Odds of HBsAg infection were 1.4 times higher among PLHIV compared to HIV-negative individuals. There is therefore, a high global burden of HIV-HBsAg co-infection, especially in sub-Saharan Africa. Key prevention strategies include infant HBV vaccination, including a timely birth-dose. Findings also highlight the importance of targeting PLHIV, especially high-risk groups for testing, catch-up HBV vaccination and other preventative interventions. The global scale-up of antiretroviral therapy (ART) for PLHIV using a tenofovir-based ART regimen provides an opportunity to simultaneously treat those with HBV co-infection, and in pregnant women to also reduce mother-to-child transmission of HBV alongside HIV.

Long-term follow-up of a Japanese patient with hepatitis B virus genotype H and human immunodeficiency virus coinfection

Hepatitis B virus (HBV) genotypes affect the pathogenesis of disease progression during the course of HBV infection. In Japan, HBV genotype H is one of the rare HBV genotypes. We recovered HBV genotype H from a blood sample from a Japanese HIV-infected patient with acute exacerbation of chronic HBV infection. Due to the development of drugs for treating HBV and HIV, HBV genotype H and HIV coinfection has been well controlled by nucleos(t)ide analogs and highly active antiretroviral therapy, respectively, from 2002 to 2019. Further study is needed with regard to HBV genotype H and its pathogenesis.

Occult hepatitis B virus infection in immunized children born to carrier mothers

BACKGROUND

The prevalence of occult hepatitis B virus (HBV) infection (OBI) in children due to mother-to-child transmission (MTCT) despite immunoprophylaxis remains controversial and is still unknown in Japan. The aim of this study was to determine the OBI prevalence in such children in Japan and identify the genomic mutations that might be associated with the pathogenesis of OBI in children.

METHODS

The data on 158 children born to HBV carrier mothers and who received complete passive-active immunoprophylaxis after birth in 2002-2014 were reviewed. HBV markers were detected using commercial enzyme-linked immunosorbent assay kits. HBV-DNA was detected using real-time and nested polymerase chain reaction. Complete genomic sequences were determined.

RESULTS

Among the 158 children studied, three had HBV MTCT: two had OBI, and one had resolved HBV infection (RBI). The prevalence of OBI and RBI was estimated to be 1.3% and 0.6%, respectively. The HBV genomes of the two OBI children were wild type and 100% identical to those of their mothers. Of these two children, one received repeated hepatitis B immunoglobulin (HBIG) and developed overt HBV infection. Her HBV genome had a G145R mutation in the S gene that might have been induced by HBIG treatment. The RBI child was persistently positive for antibody to HBV core antigen (10-12 signal/cut-off ratio; S/CO).

CONCLUSIONS

A low prevalence of OBI was observed in children who received immunoprophylaxis for preventing MTCT in Japan. The development of overt HBV infection in infants with OBI indicates the necessity of close and long-term monitoring.

Real-time PCR assays for hepatitis B virus DNA quantification may require two different targets

Background

Quantification Hepatitis B virus (HBV) DNA plays a critical role in the management of chronic HBV infections. However, HBV is a DNA virus with high levels of genetic variation, and drug-resistant mutations have emerged with the use of antiviral drugs. If a mutation caused a sequence mismatched in the primer or probe of a commercial DNA quantification kit, this would lead to an underestimation of the viral load of the sample. The aim of this study was to determine whether commercial kits, which use only one pair of primers and a single probe, accurately quantify the HBV DNA levels and to develop an improved duplex real-time PCR assay.

Methods

We developed a new duplex real-time PCR assay that used two pairs of primers and two probes based on the conserved S and C regions of the HBV genome. We performed HBV DNA quantitative detection of HBV samples and compared the results of our duplex real-time PCR assays with the COBAS TaqMan HBV Test version 2 and Daan real-time PCR assays. The target region of the discordant sample was amplified, sequenced, and validated using plasmid.

Results

The results of the duplex real-time PCR were in good accordance with the commercial COBAS TaqMan HBV Test version 2 and Daan real-time PCR assays. We showed that two samples from Chinese HBV infections underestimated viral loads when quantified by the Roche kit because of a mismatch between the viral sequence and the reverse primer of the Roche kit. The HBV DNA levels of six samples were undervalued by duplex real-time PCR assays of the C region because of mutations in the primer of C region.

Conclusions

We developed a new duplex real-time PCR assay, and the results of this assay were similar to the results of commercial kits. The HBV DNA level could be undervalued when using the COBAS TaqMan HBV Test version 2 for Chinese HBV infections owing to a mismatch with the primer/probe. A duplex real-time PCR assay based on the S and C regions could solve this problem to some extent.

Widespread hepatitis B virus genotype G (HBV-G) infection during the early years of the HIV epidemic in the Netherlands among men who have sex with men

Background

Hepatitis B virus (HBV) variants belong to different genotypes, A-J, whose worldwide distribution is linked with geography, probably because viral spread was associated with ancient human migrations. HBV genotype G (HBV-G) is an aberrant genotype with little sequence divergence, suggesting a recent origin. HBV-G is strongly associated with certain risk groups such as intravenous drug users (IDUs) and men who have sex with men (MSM), but hardly with geography. The origin and epidemiology of HBV-G remain unresolved, as is the disease association.

Methods

To estimate the prevalence and possible time of introduction of HBV-G into the MSM community in Amsterdam, the Netherlands, we have retrospectively analysed 226 blood serum samples from HBsAg positive MSM enrolled in the Amsterdam Cohort Studies (ACS) on HIV infection and AIDS dating from 1984 to 1999 using genotype-specific PCR assays.

Results

Of the 226 HBsAg-positive samples, 149 were HBV DNA positive. Of those, 104 were positive for HBV genotype A (HBV-A) and five for HBV-G, and 40 showed a dual infection with both HBV-A and HBV-G. Being HIV-infected was significantly associated with a reduced HBV DNA viral load in blood, but not with the prevalence of HBV-G. Early virus already contained stop codons in the precore region and a 36 bp insertion in the core gene which are the characteristics of HBV-G.

Conclusions

HBV-G was introduced before 1985 into the Amsterdam MSM community. Early isolates show very limited sequence variation, confirming a low evolutionary rate. HBV-G acquisition was independent of HIV infection, but being HIV-infected was significantly associated with a reduced HBV viral load in blood, indicating a beneficial effect of early HIV infection in controlling HBV replication.

Electronic supplementary material

The online version of this article (doi:10.1186/s12879-016-1599-7) contains supplementary material, which is available to authorized users.

Hepatitis B virus intergenotypic recombinants worldwide: An overview

Novel variants generated by recombination events between different hepatitis B virus (HBV) genotypes have been increasingly documented worldwide, and the role of recombination in the evolutionary history of HBV is of significant research interest. In the present study, large-scale data retrieval and analysis on HBV intergenotypic recombinant genomes were performed. The geographical distribution of HBV recombinants as well as the molecular processes involved in recombination were examined. After review of published data, a total of 436 complete HBV sequences, previously identified as recombinants, were included in the recombination detection analysis. About 60% of HBV recombinants were B/C (n=179) and C/D (n=83) hybrids. A/B/C, A/C, A/C/G, A/D, A/E, A/G, B/C/U (U=unknown genotype), C/F, C/G, C/J, D/E, D/F, and F/G hybrids were additionally identified. HBV intergenotypic sequences were reported in almost all geographical regions with similar circulation patterns as their original genotypes, indicating the potential for spreading in a wide range of human populations and developing their own epidemiology. Recombination breakpoints were non-randomly distributed in the genome, and specific favored sites detected, such as within nt 1700-2000 and 2100-2300 regions, which displayed a statistically significant difference in comparison with the remaining genome. Elucidation of the effects of recombination events on the evolutionary history of HBV is critical to understand current and future evolution trends.

Identification of Novel Recombinant Forms of Hepatitis B Virus Generated from Genotypes Ae and G in HIV-1-Positive Japanese Men Who Have Sex with Men

The rare hepatitis B virus (HBV) genotype G (HBV/G) coinfects HIV-1-positive individuals along with HBV/A and generates recombinants. However, the circulation of HBV A/G recombinants remains poorly understood. This molecular epidemiologic study examined HBV A/G recombinants in Japanese HIV-1-positive men who have sex with men (MSM). Initially, blood specimens submitted for confirmatory tests of HIV infection in Osaka and Tokyo, Japan, from 2006 to 2013 were examined for HIV-1, and HIV-1-positive specimens were screened for HBV. Among 817 specimens from HIV-1-positive individuals, HBsAg was detected in 59 specimens; of these, HBV/Ae (alternatively A2), a subgenotype of HBV/A prevalent in Europe and North America, was identified in 70.2%, HBV/C in 17.5%, and HBV/G in 10.5%, and HBV/E in 1.8% according to the core gene sequence. The full-length genome analysis of HBV was performed on HBV/G-positive specimens because some HBV A/G recombinants were historically overlooked by genotyping based on a partial genome analysis. It revealed that five of the specimens contained novel Ae/G recombinants, the core gene of which had a high sequence similarity to HBV/G. Detailed analyses showed that novel recombinants were coinfected with HBV/Ae in a recombinant-dominant fashion. No major drug-resistant mutations were found in the newly identified HBV Ae/G recombinants. Some of the individuals asymptomatically coinfected with HIV/HBV suffered mild liver injury. This study demonstrated that novel Ae/G HBV recombinants were identified in Japanese HIV-1-positive MSM. The pathogenicity of novel HBV Ae/G recombinants should be examined in a future longitudinal study. Surveillance of such viruses in HIV-1-positive individuals should be emphasized.

An adolescent female having hepatocellular carcinoma associated with hepatitis B virus genotype H with a deletion mutation in the pre-S2 region

The genotypes of hepatitis B virus (HBV) have a distinct geographical distribution, with HBV genotype H being very rare in East Asia, including Japan. We herein report the case of a 12-year-old Japanese female with hepatocellular carcinoma (HCC) who exhibited HBV genotype H. Notably, the HBV isolated from the patient had a deletion mutation in the pre-S2 region. The genome of HBV genotype H in the patient with HCC has not been analyzed in detail. The deletion mutations in the pre-S2 region, which may play an important role in hepatocarcinogenesis in children, can also present in genotype H.

Acute hepatitis B of genotype H resulting in persistent infection

A 47-year-old man presented with general fatigue and dark urine. The laboratory data showed increased levels of hepatic transaminases. The patient was positive for hepatitis B virus (HBV) markers and negative for anti-human immunodeficiency virus. The HBV-DNA titer was set to 7.7 log copies/mL. The patient was diagnosed with acute hepatitis B. The HBV infection route was obscure. The serum levels of hepatic transaminases decreased to normal ranges without any treatment, but the HBV-DNA status was maintained for at least 26 mo, indicating the presence of persistent infection. We isolated HBV from the acute-phase serum and determined the genome sequence. A phylogenetic analysis revealed that the isolated HBV was genotype H. In this patient, the elevated peak level of HBV-DNA and the risk alleles at human genome single nucleotide polymorphisms s3077 and rs9277535 in the human leukocyte antigen-DP locus were considered to be risk factors for chronic infection. This case suggests that there is a risk of persistent infection by HBV genotype H following acute hepatitis; further cases of HBV genotype H infection must be identified and characterized. Thus, the complete determination of the HBV genotype may be essential during routine clinical care of acute hepatitis B outpatients.

High prevalence of hepatitis B virus dual infection with genotypes A and G in HIV-1 infected men in Amsterdam, the Netherlands, during 2000-2011

Background

Hepatitis B virus (HBV) is divided into 8 definite (A-H) and 2 putative (I, J) genotypes that show a geographical distribution. HBV genotype G, however, is an aberrant genotype of unknown origin that demonstrates severe replication deficiencies and very little genetic variation. It is often found in co-infections with another HBV genotype and infection has been associated with certain risk groups such as intravenous drug users and men having sex with men (MSM). We aimed to estimate the prevalence of HBV-G in the Netherlands by analysing samples from HBV-positive patients visiting the Academic Medical Center in Amsterdam.

Methods

Ninety-six HBV-infected patients, genotyped as HBV-A or HBV-G infected, were retrieved from the clinical database. Blood plasma samples were analysed with a newly-developed real-time PCR assay that detects HBV-A and HBV-G. For three patients, the HBV plasma viral load (pVL) of both genotypes was followed longitudinally. In addition, three complete genomes of HBV-G were sequenced to determine their relationship to global HBV-G strains.

Results

Ten HBV-G infections were found in the selected Dutch patients. All concerned HIV-1 infected males with HBV-A co-infection. Dutch HBV-G strains were phylogenetically closely related to reference HBV-G strains.

Conclusions

In this study, HBV-G infection in the Netherlands is found exclusively in HIV-1 infected men as co-infection with HBV-A. A considerable percentage (37%) of men infected with HBV and HIV-1 are actually co- infected with two HBV genotypes.

HBV endemicity in Mexico is associated with HBV genotypes H and G

Hepatitis B virus (HBV) genotypes have distinct genetic and geographic diversity and may be associated with specific clinical characteristics, progression, severity of disease and antiviral response. Herein, we provide an updated overview of the endemicity of HBV genotypes H and G in Mexico. HBV genotype H is predominant among the Mexican population, but not in Central America. Its geographic distribution is related to a typical endemicity among the Mexicans which is characterized by a low hepatitis B surface antigen seroprevalence, apparently due to a rapid resolution of the infection, low viral loads and a high prevalence of occult B infection. During chronic infections, genotype H is detected in mixtures with other HBV genotypes and associated with other co-morbidities, such as obesity, alcoholism and co-infection with hepatitis C virus or human immunodeficiency virus. Hepatocellular carcinoma prevalence is low. Thus, antiviral therapy may differ significantly from the standard guidelines established worldwide. The high prevalence of HBV genotype G in the Americas, especially among the Mexican population, raises new questions regarding its geographic origin that will require further investigation.

Role of genotype G hepatitis B virus mixed infection on the progression of hepatic fibrosis in HIV positive patients over 5 years of follow-up

BACKGROUND

Due to common routes of transmission, HIV and HBV are frequently found as concomitant infections. The dynamic of liver disease in co-infected patients is important to understand for appropriate clinical management. Conflicting data surround the role played by genotype-G HBV (HBV-G) during the course of HIV co-infection.

OBJECTIVES

This study aims to assess, using non-invasive methods, liver disease progression in HIV-HBV genotype-G co-infected patients.

STUDY DESIGN

Co-infected patients with residual HBV replication (n=125) were screened for HBV-G infection by specific real-time PCR. The impact of HBV-G on liver fibrosis progression, as assessed by a non invasive biomarker (Fibrotest), was evaluated first, by a cross sectional analysis comparing fibrosis between HBV-G (n=23) and non-G (n=55) infected patients and second, by a longitudinal study performed over a 5 year period.

RESULTS

Selected patients were mostly male (90%), with homogenous characteristics between the HBV-G and non-G infected groups, in terms of age, known duration of HIV disease, immune and virological status and duration of HIV/HBV treatment. HBV-G infected patients were exclusively from Western Europe with homosexual intercourses (83%) as principal risk of transmission. Cross sectional analysis revealed comparable liver disease severity distribution between HBV-G and non-G infected patients. Co-infection with other hepatitis viruses and low CD4-nadir, but not HBV-G co-infection, were associated with a 5-year risk of fibrosis progression.

CONCLUSIONS

This study suggests that HBV-G infection is not significantly associated with a more severe liver disease and does not have a deleterious impact on fibrosis progression in efficiently treated HIV-HBV co-infected patients.

Molecular epidemiology and genetic diversity of hepatitis B virus in Mar del Plata city, Argentina

The aim of this work was to describe the current molecular epidemiology and genetic diversity of HBV in Mar del Plata, an important Argentinean touristic city. The phylogenetic analysis of 29 HBV DNA positive serum samples showed that F1b was the predominant subgenotype (sgt, 62.1%), followed by sgt A2 (13.8%) and sgt F4, gt D and gt G (6.9% each). Among anti-HBc IgM positive samples, 75.0% were sgt F1b, followed by sgt F4 (12.5%), sgt A2 (6.25%) and sgt D (6.25%). Three recombinant full length genomes were found: two G/F1b (some of the first gt G detected in Argentina) and one F4/D2. The circulation of clinical important mutations in the city was described. Mutations at the HBsAg were detected in 34.5% of the analyzed samples, associated with laboratory diagnosis and antiviral treatment failures, immune escape and hepatocellular carcinoma. Most of the samples presented wild type BCP/PC sequences. Coalescence analysis for the most prevalent sgt F1b estimated that the diversification mainly occured during mid '90s and the tMRCA was estimated in 1987. Finally, the high presence of the autochthonous sgt F1b, associated with the anti-HBc IgM positive infection and its present-day diversification process, shows the strong impact of internal human migratory movements into the current population of Mar del Plata.

Distribution of HBV genotypes F and H in Mexico and Central America

The distribution of HBV genotypes is associated with populations of specific geographical regions of the world. We show data from the GenBank sequence database and medical reports, which indicate that HBV genotype H (HBV/H) is mainly distributed in Mexico, whereas HBV genotype F (HBV/F) is distributed in countries from Central America. The phylogenetic analysis and historical records suggest that HBV/H has been present in Mexico even before the arrival of the Spaniards. Interestingly, occult hepatitis B is a common finding in both natives and patients with chronic liver disease in Mexico. This suggests that an immunogenic background could be important during the natural history of liver diseases. The estimated large number of HBV/H-infected patients in Mexico does not correlate with the total number of patients with chronic liver disease and cirrhosis reported in the country. This may be because of the fact that HBV infection is often masked by alcoholic liver disease, HCV coinfection and/or obesity. Here, we analyse the data concerning the distribution of HBV/F and HBV/H genotypes in Central America and Mexico. Specifically, we focus on the effect of molecular epidemiology and pathogenesis of HBV/H. These recent findings reveal new areas of study with therapeutic potential in viral liver diseases.

Prevalence of hepatitis B virus and hepatitis C virus in patients with human immunodeficiency virus infection in Central China

Co-infection of hepatitis B virus (HBV) and/or hepatitis C virus (HCV) with human immunodeficiency virus (HIV) has an adverse effect on liver disease progression. This study investigated the prevalence of HBV and/or HCV co-infection in HIV-infected patients in Central China. A total of 978 HIV-infected patients from Hunan Province were enrolled. HBV serum markers, anti-hepatitis-C-virus antibody (anti-HCV), HBV DNA, and HBV genotypes were analyzed. The prevalence of hepatitis B surface antigen (HBsAg) and anti-HCV in HIV-infected patients was 19.4 % and 62.4 %, respectively. The prevalence of anti-HCV in HIV-positive intravenous drug users was 93.6 %. Among HBsAg-positive patients, 88.1 % were found to have at least one HBV serum marker. The rates of HIV mono-infection, HBV/HIV dual infection, HCV/HIV dual infection, and HBV/HCV/HIV triple infection were 30.4 %, 7.2 %, 50.2 %, and 12.2 %, respectively. Antibody to HBsAg (Anti-HBs) was more common in anti-HCV-positive than anti-HCV-negative patients (53.3 % vs 40.2 %, P = 0.000), but isolated hepatitis B core antibody (anti-HBc) was more common in anti-HCV-negative than anti-HCV-positive patients (24.2 % vs 12.3 %, P = 0.000). Hepatitis B e antigen (HBeAg) and sexual transmission were independent risk factors for active HBV replication. Intravenous drug use and male sex were independent risk factors, but old age and presence of HBeAg were independent protective factors for anti-HCV. Co-infection of HBV and/or HCV with HIV infection is common in central China. HCV status is associated with anti-HBs and isolated anti-HBc in co-infected patients.

Comparative analysis of CpG islands among HBV genotypes

DNA methylation is being increasingly recognized to play a role in regulation of hepatitis B virus (HBV) gene expression. The aim of this study was to compare the CpG island distribution among different HBV genotypes. We analyzed 176 full-length HBV genomic sequences obtained from the GenBank database, belonging to genotypes A through J, to identify the CpG islands in the HBV genomes. Our results showed that while 79 out of 176 sequences contained three conventional CpG islands (I–III) as previously described, 83 HBV sequences harbored only two of the three known islands. Novel CpG islands were identified in the remaining 14 HBV isolates and named as CpG island IV, V, and VI. Among the eight known HBV genotypes and two putative genotypes, while HBV genomes containing three CpG islands were predominant in genotypes A, B, D, E, and I; genotypes C, F, G, and H tended to contain only two CpG islands (II and III). In conclusion, the CpG islands, which are potential targets for DNA methylation mediated by the host functions, differ among HBV genotypes, and these genotype-specific differences in CpG island distribution could provide new insights into the understanding of epigenetic regulation of HBV gene expression and hepatitis B disease outcome.

The distribution of hepatitis B virus genotypes in Thailand

Phylogenetic analysis was performed on hepatitis B virus (HBV) strains obtained from 86 hepatitis B surface antigen (HBsAg) positive donors from Thailand originating throughout the country. Based on the S gene, 87.5% of strains were of genotype C while 10.5% were of genotype B, with all genotype B strains obtained from patients originating from the central or the south Thailand. No genotype B strains were found in the north of Thailand. Surprisingly, one patient was infected with a genotype H strain while another patient was infected with a genotype G strain. Complete genome sequencing and recombination analysis identified the latter as being a genotype G and C2 recombinant with the breakpoint around nucleotide position 700. The origin of the genotype G fragment was not identifiable while the genotype C2 fragment most likely came from strains circulating in Laos or Malaysia. The performance of different HBsAg diagnostic kits and HBV nucleic acid amplification technology (NAT) was evaluated. The genotype H and G/C2 recombination did not interfere with HBV detection.

Identification of novel recombinants of hepatitis B virus genotypes F and G in human immunodeficiency virus-positive patients from Argentina and Brazil

Hepatitis B virus (HBV) genotype G (HBV/G) infection is almost always detected along with a co-infecting HBV strain that can supply HBeAg, typically HBV/A2. In this study we describe, in two human immunodeficiency virus (HIV)-positive patients from Argentina and Brazil, the first report of HBV/G infection in Argentina and co-circulation of HBV/G, HBV/F and G/F recombinants in the American continent. HBV isolates carrying the 36 bp insertion of HBV/G were the most prevalent in both patients, with >99 % of colonies hybridizing to a probe specific for this insertion. Phylogenetic analyses of full-length genomes and precore/core fragments revealed that F4 and F1b were the co-infecting subgenotypes in the Brazilian and Argentinian patients, respectively. Bootscanning analysis provided evidence of recombination in several clones from both patients, with recombination breakpoints located mainly at the precore/core region. These data should encourage further investigations on the clinical implications of HBV/G recombinants in HBV/HIV co-infected patients.

Hepatitis B virus with a proposed genotype I was found in Sichuan Province, China

To date, eight hepatitis B virus (HBV) genotypes, A-H, have been designated, and two additional genotypes, I and J, have also been proposed. A serological survey targeting children in difficult-to-reach vaccination areas was carried out in remote counties of Sichuan Province, China. HBV genotypes and serotypes were also determined from HBsAg-positive serum samples by direct sequencing. Phylogenetic analysis showed two strains isolated from the Yi ethnic children clustered with the proposed genotype I. The pairwise genome genetic distance was 7.5% between genotypes I and C, and ranged from 8.4% to 15.2% between genotype I and other genotypes, except genotype C. Grouping Scan analyses of the two strains revealed apparent recombination events between an unknown genotype and genotype C. Two out of four HBV strains isolated from the Yi ethnic children were confirmed to be genotype I, suggesting widespread circulation and common infection with genotype I HBV in the local Yi population. High prevalence of HBsAg and low hepatitis B vaccination coverage indicated that additional efforts are needed to control HBV infection in those areas.

Chronic hepatitis B in patients coinfected with human immunodeficiency virus in Japan: a retrospective multicenter analysis

A nationwide survey in Japan revealed that about 6 % of human immunodeficiency virus (HIV)-positive patients are coinfected with hepatitis B virus (HBV). To further analyze the features of liver disease in HIV/HBV-coinfected patients, we analyzed 252 patients from six hospitals in the HIV/AIDS (acquired immunodeficiency syndrome) Network of Japan. The mean age was 39.5 years, and the proportion of male patients was very high (243 of 252; 96 %). The main transmission route was male homosexual contact (186 of 252; 74 %), followed by heterosexual contact. The HBV genotype was determined in 77 patients. Among them, genotype A HBV was the most frequent (58 of 77; 75 %) and was detected almost exclusively in homosexual patients. Acute hepatitis B was documented in 21 patients (8 %). Three of the 252 HIV/HBV-coinfected patients developed advanced liver disease with the complication of ascites, hepatic encephalopathy, or hepatocellular carcinoma. A comparison between patients not treated and those treated with antiretroviral drugs including anti-HBV drugs revealed that the baseline liver function was worse in treated patients. However, the serum albumin levels and platelet counts in both groups increased after treatment and were similar. Liver disease-associated death was not observed. Here, we characterize the clinical features of liver disease in HIV/HBV-coinfected patients in Japan for the first time. The findings suggest that antiretroviral therapy with anti-HBV drugs may retard the progression of a liver disease and prevent liver disease-associated death in such patients.

Molecular characterization of hepatitis B virus strains circulating in Belgian patients co-infected with HIV and HBV: overt and occult infection

Hepatitis B virus (HBV) and human immunodeficiency virus (HIV) have similar transmission routes, implying that patients infected with HIV are at particular risk for HBV infection. Patients who are co-infected with HIV and HBV progress more rapidly to end-stage liver disease and different HBV genotypes may have a distinct impact on disease progression. One hundred ninety-one anti-HBc-positive sera from Belgian patients co-infected with HIV and HBV were collected during 1998-2008. Full-length HBV genomes as well as large S or partial S genes were amplified and their molecular evolutionary history was analyzed. Clinically, 30 (65.8%) patients were categorized as "overt infection" and 16 (34.7%) cases were categorized as "occult infection." Five distinct HBV genotypes comprising A (69.6%), E (19.6%), followed by D, C, and G were detected. HBV genotype A was observed in all clinical groups and in patients with varying ethnical background. HBV genotype E could be detected in African patients who were mostly infected by heterosexual contacts. Several clinically important mutations at the HBs major hydrophilic region were detected in the new isolates but with no significant difference between occult and overt infection. The high prevalence of HBV genotype A in overt and occult cases, and in particular the detection of certain HBV subgenotypes in patients co-infected with HIV and HBV that carry diagnostic escape mutations, may provide useful information for national guidelines for prophylaxis and treatment.

Development of a new duplex real-time polymerase chain reaction assay for hepatitis B viral DNA detection

BACKGROUND

Quantification of hepatitis B virus (HBV) DNA can be used for diagnosing HBV infection and monitoring the effect of antiviral therapy. However, probably because of mismatches between the template and primer/probe, HBV DNA in some HBV infections could not be detected using currently available commercial assays with single primer/probe. By aligning the HBV sequences, we developed a duplex real-time polymerase chain reaction (PCR) assay using two sets of primers/probes and a specific armored DNA as internal control (IC).

RESULTS

The limit of the duplex real-time PCR assay was 29.5 IU/ml, whereas the specificity was 100%. The within-run precision coefficient of variation (CV) ranged from 1.02% to 2.73%, while the between-run CV ranged from 0.83% to 1.25%. The optimal concentration of armored DNA IC in the HBV DNA duplex real-time PCR assay was 1 000 copies/ml. Data from 69 serum samples with HBV infection showed that the performance of the duplex real-time PCR assay was comparable to that of the COBAS Ampliprep/Cobas Taqman (CAP/CTM) HBV assay and was superior to those of the domestic commercial HBV assays.

CONCLUSIONS

The duplex real-time PCR assay is sufficiently sensitive, specific, accurate, reproducible and cost-effective for the detection of HBV DNA. It is suitable for high throughput screening and frequent HBV DNA level monitoring.

Hepatitis B virus infection from an evolutionary point of view: how viral, host, and environmental factors shape genotypes and subgenotypes

Hepatitis B virus (HBV) has an overwhelming distribution in the world and causes important human health problems. It has infected one-third of the global population and more than 350 million people are chronic carriers. Several aspects of HBV infection confer adaptive advantages that lead to a highly efficient dissemination of the virus through different routes of transmission. HBV genotypes and subgenotypes have been associated with differences in clinical and virological characteristics, indicating that they may play a role in the virus-host relationship. In particular, a clear association between genotype A and chronic outcomes in both children and adults depending on the subgenotype involved, and between genotype C and a higher risk of complications from HBV infection, has been demonstrated. Interestingly, subgenotype A2 and genotype C are respectively likely to predominate in high-risk groups for sexual transmission and in areas where perinatal transmission is the major mode of HBV dissemination. An evolutionary approach to HBV infection, based on the principles of natural selection, may offer explanations for how modes of transmission may favor some genotypes and subgenotypes over others and, ultimately, influence HBV virulence.

Management of hepatitis B: Consensus of the Japan Society of Hepatology 2009

Recently, much progress has been made in the field of hepatitis B, such as natural history of the disease in relation to the amount of hepatitis B virus (HBV) DNA, genotypes of HBV influencing the natural course and treatment effects, mutations of HBV influencing the severity of the disease and development of hepatocellular carcinoma, and antiviral treatment such as nucleos(t)ide analogues and pegylated interferon. To make the consensus for the diagnosis, management and treatment of hepatitis B, a meeting was held during 45th annual meeting of Japan Society of Hepatology (JSH) in June 2009. In the meeting, recommendations and informative statements were discussed on the following subjects: (i) natural history of HBV infection; (ii) clinical implication of HBV genotypes; (iii) HBV mutations and their potential impact on pathogenesis of HBV infection; (iv) indications for antiviral treatment of chronic hepatitis B; (v) nucleos(t)ide analogues for chronic hepatitis B; and (vi) interferon therapy for chronic hepatitis B. The presenters reviewed the data on these subjects and proposed the consensus statements and recommendations. These statements were discussed among the organizers and presenters, and were approved by the participants of the meeting. In the current report, the relevant data were reviewed and the 12 consensus statements and nine recommendations on chronic hepatitis B were described.

Molecular characterization of the Hepatitis B virus genotypes in Colombia: a Bayesian inference on the genotype F

Hepatitis B is a worldwide health problem affecting about 2 billion people and more than 350 million are chronic carriers of the virus. Nine HBV genotypes (A to I) have been described. The geographical distribution of HBV genotypes is not completely understood due to the limited number of samples from some parts of the world. One such example is Colombia, in which few studies have described the HBV genotypes. In this study, we characterized HBV genotypes in 143 HBsAg-positive volunteer blood donors from Colombia. A fragment of 1306 bp partially comprising HBsAg and the DNA polymerase coding regions (S/POL) was amplified and sequenced. Bayesian phylogenetic analyses were conducted using the Markov Chain Monte Carlo (MCMC) approach to obtain the maximum clade credibility (MCC) tree using BEAST v.1.5.3. Of all samples, 68 were positive and 52 were successfully sequenced. Genotype F was the most prevalent in this population (77%) - subgenotypes F3 (75%) and F1b (2%). Genotype G (7.7%) and subgenotype A2 (15.3%) were also found. Genotype G sequence analysis suggests distinct introductions of this genotype in the country. Furthermore, we estimated the time of the most recent common ancestor (TMRCA) for each HBV/F subgenotype and also for Colombian F3 sequences using two different datasets: (i) 77 sequences comprising 1306 bp of S/POL region and (ii) 283 sequences comprising 681 bp of S/POL region. We also used two other previously estimated evolutionary rates: (i) 2.60 × 10(-4)s/s/y and (ii) 1.5 × 10(-5)s/s/y. Here we report the HBV genotypes circulating in Colombia and estimated the TMRCA for the four different subgenotypes of genotype F.

[Development and validation of a specific method for relative HBV-genotype G (G-HBV) quantification in the context of co-infection with other genotypes]

GOAL OF THE STUDY

A detection and quantification method specific of genotype G hepatitis B virus (G-HBV) was developed and used to study the epidemiology and evolution of G-HBV co-infection during antiviral therapy.

PATIENTS AND METHODS

A multiplex real time PCR was developed and validated on A-HBV and G-HBV plasmid mixes. G-HBV infection was sought for on chronic hepatitis B carriers followed in our institution.

RESULTS

Two primers, flanking the specific G-HBV 36 nucleotide insertion and two probes, including one specific for the insertion, were validated for a multiplex real time PCR. This new tool was well correlated to commercially available quantification systems within a 2 to 7 log(10) IU/mL range. On A- and G-HBV clonal mixes, G-HBV was quantified with a precision between 5 to 10%. On HBV-HIV infected patients, a 25% G-HBV prevalence was found, while it was below 1% in HBV mono-infected patients. Longitudinal G-HBV quantifications on five treated patients indicate that G-HBV is not selected by antiviral treatment.

CONCLUSION

A specific method for G-HBV quantification within multi-genotype mixes was set up. The important G-HBV prevalence in HIV patients was unexpected. Our data are not in favour of an intrinsic resistance of G-HBV to current antivirals.

A novel HBV recombinant (genotype I) similar to Vietnam/Laos in a primitive tribe in eastern India

Genotyping of 20 strains of Hepatitis B virus (HBV) from the Idu Mishmi primitive tribe of northeast India identified multiple genotypes and the presence of a unique cluster grouping with strains from Vietnam and Laos identified as novel recombinants/genotype I. Sequence analysis (similarity and bootscan plots) of three complete HBV genomes from the tribe provided evidence of recombination. Phylogenetic analyses supported recombination between genotypes A, G and C. The Pre-S gene between nt 2943 and 397 was clearly of genotype A origin, whereas nt 397-1397 represented genotype G and nt 1397-2943 represented genotype C. Percentage divergence from genotypes B, D, E, F, G and H varied from 9.2 +/- 0.45% to 13.8 +/- 0.53%, whereas genotype A and C differed by 7.9 +/- 0.42% and 7.4 +/- 0.39% respectively. The identification of similar recombinant viruses in three countries, especially in a primitive tribe with no contact with the outside world suggests that these viruses do not represent recent recombination events, but circulation of closely related viruses highly divergent from known HBV genotypes and should be classified as members of genotype 'I'.

Geographical and genetic diversity of the human hepatitis B virus

Hepatitis B virus (HBV) is one of the most widely distributed viruses that infect humankind. Distinct clinical and virological characteristics of the HBV-infection have been reported in different geographical parts of the world and are increasingly associated with genetic diversity of the infecting virus. HBV is classified into genotypes and subgenotypes that are associated with ethnicity and geography. The genetic diversity of HBV in its various aspects has been the subject of extensive investigations during the last few decades. Since molecular epidemiology research tools have become widely available, the number of new publications in this field has grown exponentially. This review summarises the recent publications on the geographical distribution of genetic variants of HBV, and proposes updated criteria for the identification of new genotypes and subgenotypes of the virus.

Virological pattern of hepatitis B infection in an HIV-positive man with fatal fulminant hepatitis B: a case report

INTRODUCTION

There seem to be no published data concerning the clinical impact of populations of hepatitis B virus (HBV) in the hepatic and extrahepatic compartments of HIV-infected people with severe acute hepatitis.

CASE PRESENTATION

A 26-year-old Caucasian man presenting to our hospital with clinical symptoms suggesting acute hepatitis was found to have an acute hepatitis B profile upon admission. He developed fatal fulminant hepatitis and was found to be heavily immunocompromised due to HIV-1 infection. He had a high plasma HBV and HIV load, and analysis of the partial pre-S1/pre-S2 domain showed the presence of mixed infection with D and F genotypes. Analysis of the point mutations within this region revealed the presence of HBV strains with amino acid substitutions at the immunodominant epitopes involved in B or T cell recognition. A homogeneous population of a pre-core mutant strain harbouring the A1896G and A1899G affecting HBeAg expression was invariably found in the liver tissue, plasma and peripheral blood mononuclear cells despite active HBeAg secretion; it was the dominant strain in the liver only, and was characterised by the presence of two point mutations in the direct repeat 1 domain involved in HBV replication activity. Taken together, these mutations are indicative of a highly replicative virus capable of evading immune responses.

CONCLUSION

This case report provides clinical evidence of a possible association between the rapid spread of highly replicative escape mutants and the development of fulminant hepatitis in a heavily immunocompromised patient. Virological surveillance of severe acute hepatitis B may be important in establishing an early treatment strategy involving antiviral drugs capable of preventing liver failure, especially in individuals for whom liver transplantation is not accepted as a standard indication.

A nationwide molecular epidemiological study on hepatitis B virus in Indonesia: identification of two novel subgenotypes, B8 and C7

Upon phylogenetic analysis of a partial S gene sequence [396 nucleotides (nt)], 928 hepatitis B virus (HBV) strains obtained from 899 viremic subjects in 28 major cities on 15 islands of Indonesia in 1989-2007 segregated into four HBV genotypes. Genotype B was predominant (66%), followed by genotype C (26%), genotype D (7%), and genotype A (0.8%). Comparative and phylogenetic analyses of the 396-nt S gene sequence of 928 HBV isolates and whole genomic sequences of 25 selected HBV isolates revealed a total of 14 subgenotypes within genotypes A-D: two (A1 and A2) in genotype A (HBV/A), five (B2, B3, B5, B7, and a novel subgenotype, tentatively designated B8) in HBV/B, five (C1, C2, C5, C6, and another novel subgenotype, C7) in HBV/C, and two (D1 and D3) in HBV/D. The distribution of HBV genotypes/subgenotypes, including B8 and C7, seems to be associated with ethnological origins in Indonesia.

Distribution of hepatitis B virus genotypes among patients with chronic infection in Japan shifting toward an increase of genotype A

Acute hepatitis B virus (HBV) infection has been increasing through promiscuous sexual contacts, and HBV genotype A (HBV/A) is frequent in patients with acute hepatitis B (AHB) in Japan. To compare the geographic distribution of HBV genotypes in patients with chronic hepatitis B (CHB) in Japan between 2005 and 2006 and between 2000 and 2001, with special attention to changes in the proportion of HBV/A, a cohort study was performed to survey changes in genotypes of CHB patients at 16 hospitals throughout Japan. Furthermore, we investigated the clinical characteristics of each genotype and examined the genomic characteristics of HBV/A isolates by molecular evolutionary analyses. Of the 1,271 patients, 3.5%, 14.1%, and 82.3% were infected with HBV/A, -B, and -C, respectively. In comparison with our previous survey during 2000 and 2001, HBV/A was twice as frequent (3.5% versus 1.7%; P = 0.02). The mean age was lower in the patients with HBV/A than in those with HBV/B or -C. Based on phylogenetic analyses of 11 full-length genomes and 29 pre-S2/S region sequences from patients, HBV/A isolates were imported from Europe and the United States, as well as the Philippines and India. They clustered with HBV/A from AHB patients and have spread throughout Japan. HBV/A has been increasing in CHB patients in Japan as a consequence of AHB spreading in the younger generation through promiscuous sexual contacts, aided by a tendency of HBV/A to induce chronic hepatitis. The spread of HBV/A infection in Japan should be prevented by universal vaccination programs.

Possible new hepatitis B virus genotype, southeast Asia

We conducted a phylogenetic analysis of 19 hepatitis B virus strains from Laos that belonged to 2 subgenotypes of a new genotype I. This emerging new genotype likely developed outside Southeast Asia and is now found in mixed infections and in recombinations with local strains in a geographically confined region.

Hepatitis B virus genotype G epidemiology and co-infection with genotype A in Canada

Hepatitis B virus (HBV) genotype G (HBV/G) is an unusual variant, and little is known about its epidemiology and natural history, particularly the requirement for a co-infecting HBV genotype and their relationship during infection. This study investigated the quasispecies nature of co-infecting genotypes in 39 samples collected over a 6 year period from 13 HBV/G-infected patients. HBV/G infections were found to occur predominantly in males (92 %) and were primarily associated with male homosexual sex (67 %). All patients were infected with HBV/G and HBV/A, or a recombinant HBV/A/G strain. Co-infecting genotypic prevalence was often observed to fluctuate over time, with periods of HBV/G monoinfection in some patients. The average sequence divergence among Canadian HBV/G strains was 1.57+/-0.62 %. Thus, all HBV/G infections in Canada occur in the context of co-infection or recombination with HBV/A, and strains display increased sequence divergence compared with all known HBV/G sequences described to date.

Genotype D amongst injection drug users with acute hepatitis B virus infection in British Columbia

The eight genotypes of hepatitis B virus (HBV) exhibit distinct geographical distributions. This study identified HBV genotypes and transmission modes associated with acute infection in British Columbia (BC), Canada, from 2001 to 2005. Seventy cases of acute HBV in BC were identified from laboratory reports using a standardized case definition. Interviews for risk factors and hepatitis history were conducted for each case. HBV genotypes were determined by BLAST comparison analysis of the surface (S) or preS gene sequence. To illustrate the distribution of genotypes identified amongst acute cases in BC, an annotated map was produced showing the global occurrence of HBV genotypes. The majority of acute HBV cases occurred in Caucasian, Canadian-born males, with 30% of cases reporting injection drug use (IDU) and 21% reporting incarceration. The most common genotype observed was genotype D (62.9%), followed by genotypes A (18.6%), C (11.4%), B (4.3%), and E (1.4%). A significant association was observed between Genotype D and IDU (P = 0.0025) and previous incarceration (P = 0.0067). Phylogenetic analysis of the S gene sequence demonstrated identical or high genetic relatedness amongst genotype D viral strains (86% sub-genotype D3), thus verifying transmission clustering amongst BC injection drug users. The association between acute HBV genotype and reported transmission modes has not been previously described in North America. Tracking of genotypes can help identify disease transmission patterns and target at-risk populations for preventive immunization.

A case of HIV co-infected with hepatitis B virus precore/core deletion mutant treated by entecavir

We report a case of a HIV and hepatitis B virus (HBV)-co-infected patient to whom entecavir (ETV) was administered initially before the notification regarding the potential mutagenesis effect on HIV against the nucleoside analog. Since initial evaluations indicated the advanced stage of chronic hepatitis B and preserved numbers of peripheral CD4+ lymphocytes without the manifestation of immunodeficiency, priority was given to the management of HBV. We started HBV therapy with ETV at a dose of 0.5 mg daily without using any HIV drugs. The viral loads of both HBV and HIV-1 decreased gradually during the 5 months following the initial administration of ETV. HBV was well controlled by the gradual replacement of ETV with highly-active antiretroviral therapy against HIV with a regimen including atazanavir, emtricitabine, and tenofovir. HBV was genotyped as A2 with the quasispecies pool consisting of the -1G precore/core deletion mutant strain.

A male patient with severe acute hepatitis who was domestically infected with a genotype H hepatitis B virus in Iwate, Japan

Although all eight genotypes of hepatitis B virus (HBV) strains are circulating in Japan, no cases of acute hepatitis with foreign HBV strains of genotype H have thus far been reported in Japan. Here, we report a 35-year-old Japanese patient with severe acute hepatitis who was domestically infected with genotype H HBV. On admission, he had a high HBV load of 1.0 x 10(9) copies/ml, elevated levels of total bilirubin (7.0 mg/dl) and alanine aminotransferase (3606 IU/l), and reduced prothrombin activity of 39.0%. The HB-JAIW05 isolate obtained in the present study was composed of 3215 nucleotides and had the highest similarity of 99.7% with the reported genotype H HBV isolate recovered from a Japanese blood donor. The HB-JAIW05 isolate had neither precore (A1896) nor core promoter (T1762/A1764) mutations. However, upon comparison with the consensus sequence of ten reported HBV isolates of the same genotype, the HB-JAIW05 isolate had 17 nucleotide substitutions including five missense mutations in the P gene, which may be related to vigorous replication of HBV in this case. He had no history of traveling abroad, but had had extramarital sexual contact with two Japanese women living in Iwate, Japan, 2 weeks and 2 months before the disease onset, respectively. Our results suggest that rare HBV genotypes such as H may be spreading in Japan via sexual contact. Further molecular epidemiological studies on HBV to clarify the exact changing profiles of de novo HBV infection in Japan in relation to genotype and genomic variability are warranted.

Prolonged hepatitis after acute infection with genotype H hepatitis B virus

We present a case report of a Japanese patient who showed prolonged infection after acute hepatitis B with genotype H. The patient was a 60-year-old man who underwent an annual health care check every year for several years and was never pointed out to have any liver damage, and markers for hepatitis B and C were negative. He was found to be positive for hepatitis B surface antigen (HBsAg) at his health care check in December 2005. After one month, he had an elevated aminotransferase level with hepatitis B e antigen and a high level of serum HBV DNA. He was diagnosed as having acute hepatitis B. On HBV genotype, he had genotype H by the direct sequence method, and he was given a 100 mg of lamivudine daily. However, his acute hepatitis tended to go toward prolonged infection. After two months, he was treated with interferon daily for 28 days. He had negative HBsAg in August 2006. Genotype H, the newest type of hepatitis B, could be the type which shows a poor response to lamivudine. The present paper is the first report, describing the clinical course of acute hepatitis B with genotype H from onset to remission.

Heterogeneity of Hepatitis B Virus Genotype D in Japan

OBJECTIVE

Hepatitis B virus (HBV) genotypes B and C are predominant in Japan. Previously, we reported that approximately 9% of HBV carriers in the Ehime area of western Japan were infected with genotype D (HBV/D) and their sequences closely related. Recently, serum samples from 3 patients with chronic HBV/D infections living in Tokyo and the surrounding area became available for testing. The purpose of this study was to determine whether the HBV/D isolates from these different areas of Japan are closely related.

METHODS

Of the 3 Tokyo area patients infected with HBV/D, 2 had chronic hepatitis, and 1 had hemophilia with a history of frequent coagulation factor injections. The complete HBV/D genome sequences of each were determined, and compared with those of subjects from the Ehime area.

RESULTS

All 3 HBV/D sequences had a genomic length of 3,182 bases, and the hepatitis B surface antigen subtype was ayw3. Phylogenetic analysis revealed that the 1 of the HBV/D isolates was closely related to the isolates from Ehime Prefecture, while 1 was similar and 1 was clearly distinct.

CONCLUSION

Our results indicate that HBV/D infections in Japan are heterogeneous.

Molecular analysis of hepatitis B virus isolates in Mexico: Predominant circulation of hepatitis B virus genotype H

AIM: To determine the genotypes in Mexican hepatitis B virus (HBV) isolates and characterize their precore and core promoter mutations.

METHODS: Forty-nine HBV isolates of Mexico obtained from sera of 15 hepatitis patients, 6 hemodialysis patients, 20 men seeking HIV testing, and 8 AIDS patients were analyzed. HBV isolates were amplified by PCR, and genotyped by line probe assay (INNO-LiPA HBV Genotyping; INNOGENETICS N V, Ghent, Belgium). HBV genotype confirmation was performed by DNA sequencing part of the sAg region. Precore and core promoter mutation characterization was performed by line probe assay (INNO-LiPA HBV PreCore; INNOGENETICS N V, Ghent, Belgium).

RESULTS: Overall, HBV genotype H was found in 37 (75.5%) out of the 49 isolates studied. HBV genotypes G, A, and D were found in 5 (10.2%), 4 (8.2%), and 3 (6.1%) isolates, respectively. HBV genotype H was predominant in isolates from hemodialysis patients (100%), hepatitis patients (80%), and men seeking HIV testing (75%), and accounted for half of infections in AIDS patients (50%). Six (12.2%) out of the 49 HBV isolates showed both wild type and mutant populations at precore codon 28. These mixed wild type and precore mutant populations were observed in one HBV genotype A isolate and in all HBV genotype G isolates. A dual variant core promoter mutation was observed in 1 (2%) of the isolates, which was genotype H.

CONCLUSION: HBV genotype H is highly predominant in HBV isolates of Mexico followed by genotypes G, A and D. A low frequency of precore and core promoter mutations is observed in HBV Mexican isolates.

Hepatitis B virus genotype G monoinfection and its transmission by blood components

An acute hepatitis B virus (HBV) infection was diagnosed in a regular apheresis (plasma/platelet) donor by the hepatitis B surface antigen (HBsAg) assay and minipool nucleic acid amplification technology (NAT). The acute infection was confirmed by detection of anti-HBc (IgM) and anti-HBs 2 weeks later. The donor showed no clinical symptoms and had normal alanine aminotransferase levels. He had a history of weekly apheresis plasma or platelet donations. Archived material from the donor and the respective recipients was investigated by sensitive HBV NATs as part of a look-back procedure. HBV DNA was detectable in previous donations as well as in two recipients transfused with platelet concentrates. The rare HBV genotype G was identified in all HBV-DNA-positive samples. Strong evidence of genotype G monoinfection was obtained by clonal sequencing, HBV genotype line probe assay, genotype-specific NATs, and restriction pattern analysis. In contrast to previously described genotype G infections, which all appeared as coinfections with genotype A, neither the hepatitis B e antigen (HBeAg) nor anti-HBe was detectable in any of the samples. This shows that HBeAg is dispensable for viral replication. The delay in detecting HBsAg in both the donor and recipient samples may be explained by either decreased genotype G-specific synthesis of incomplete viral forms in early HBV infection or the lower sensitivity to genotype G of the current HBsAg assays. In conclusion, this reported case of an HBV infection was caused exclusively by genotype G.