Community-Based Screening for Hepatitis B and C Infectivity Using Two Quantitative Antigens to Identify Endemic Townships

Screening and linkage to care are essential to achieve viral hepatitis elimination before 2030. The accurate identification of endemic areas is important for controlling diseases with geographic aggregation. Viral activity drives prognosis of chronic hepatitis B and hepatitis C virus infection. This screening was conducted in Chiayi County from 2018–2019. All residents aged 30 years or older were invited to participate in quantitative HBsAg (qHBsAg) and HCV Ag screening. Among the 4010 participants (male:female = 1630:2380), the prevalence of qHBsAg and HCV Ag was 9.9% (396/4010) and 4.1% (163/4010), respectively. High-prevalence townships were identified, three for qHBsAg > 15% and two for HCV Ag > 10%. The age-specific prevalence of qHBsAg was distributed in an inverse U-shape with a peak (16.0%, 68/424) for subjects in their 40 s; for HCV, prevalence increased with age. Concentrations of qHBsAg < 200 IU/mL were found in 54% (214/396) of carriers. The rate of oral antiviral treatment for HCV was 75.5% (114/151), with subjects younger than 75 years tending to undergo treatment (85.6% vs. 57.4%, p < 0.001). QHBsAg and HCV Ag core antigens can reflect the concentration of the viral load, which serves as a feasible screening tool. Using quantitative antigen screening for hepatitis B and C in community-based screening, two hyperendemic townships were identified from an endemic county.

Differences in prevalence of hepatitis B virus infection and genotypes between ethnic populations in Suriname, South America

Epidemiological data on hepatitis B virus (HBV) are needed to benchmark HBV elimination goals. We recently assessed prevalence of HBV infection and determinants in participants attending the Emergency Department in Paramaribo, Suriname, South America. Overall, 24.5% (95%CI = 22.7-26.4%) of participants had anti-Hepatitis B core antibodies, which was associated with older age (per year, adjusted Odds Ratio [aOR] = 1.03, 95%CI = 1.02-1.04), Afro-Surinamese (aOR = 1.84, 95%CI = 1.52-2.19) and Javanese ethnicity (aOR = 1.63, 95%CI = 1.28-2.07, compared to the grand mean). 3.2% of participants were Hepatitis B surface Ag-positive, which was also associated with older age (per year, aOR = 1.02, 95%CI = 1.00-1.04), Javanese (aOR = 4.3, 95%CI = 2.66-6.95) and Afro-Surinamese ethnicity (aOR = 2.36, 95%CI = 1.51-3.71). Sex, nosocomial or culturally-related HBV transmission risk-factors were not associated with infection. Phylogenetic analysis revealed strong ethnic clustering: Indonesian subgenotype HBV/B3 among Javanese and African subgenotypes HBV/A1, HBV/QS-A3 and HBV/E among Afro-Surinamese. Testing for HBV during adulthood should be considered for individuals living in Suriname, specifically with Javanese and Afro-Surinamese ancestry.

Low Genetic Diversity of Hepatitis B Virus Surface Gene amongst Australian Blood Donors

Variants in the small surface gene of hepatitis B virus (HBV), which codes for viral surface antigen (HBsAg), can affect the efficacy of HBsAg screening assays and can be associated with occult HBV infection (OBI). This study aimed to characterise the molecular diversity of the HBV small surface gene from HBV-reactive Australian blood donors. HBV isolates from 16 HBsAg-positive Australian blood donors' plasma were sequenced and genotyped by phylogenies of viral coding genes and/or whole genomes. An analysis of the genetic diversity of eight HBV small surface genes from our 16 samples was conducted and compared with HBV sequences from NCBI of 164 international (non-Australian) blood donors. Genotypes A-D were identified in our samples. The region of HBV small surface gene that contained the sequence encoding the 'a' determinant had a greater genetic diversity than the remaining part of the gene. No escape mutants or OBI-related variants were observed in our samples. Variant call analysis revealed two samples with a nucleotide deletion leading to truncation of polymerase and/or large/middle surface amino acid sequences. Overall, we found that HBV small surface gene sequences from Australian donors demonstrated a lower level of genetic diversity than those from non-Australian donor population included in the study.

Molecular Mechanisms during Hepatitis B Infection and the Effects of the Virus Variability

The immunopathogenesis and molecular mechanisms involved during a hepatitis B virus (HBV) infection have made the approaches for research complex, especially concerning the patients’ responses in the course of the early acute stage. The study of molecular bases involved in the viral clearance or persistence of the infection is complicated due to the difficulty to detect patients at the most adequate points of the disease, especially in the time lapse between the onset of the infection and the viral emergence. Despite this, there is valuable data obtained from animal and in vitro models, which have helped to clarify some aspects of the early immune response against HBV infection. The diversity of the HBV (genotypes and variants) has been proven to be associated not only with the development and outcome of the disease but also with the response to treatments. That is why factors involved in the virus evolution need to be considered while studying hepatitis B infection. This review brings together some of the published data to try to explain the immunological and molecular mechanisms involved in the different stages of the infection, clinical outcomes, viral persistence, and the impact of the variants of HBV in these processes.

A3G-induced mutations show a low prevalence and exhibit plus-strand regional distribution in hepatitis B virus DNA from patients with non-hepatocellular carcinoma (HCC) and HCC

APOBEC3G (A3G) cytidine deaminase is an innate immune restriction factor that can edit and inhibit hepatitis B virus (HBV) replication. The preferred target of A3G is deamination of the third cytosine of 5'CCC to form a mutant marker 5'CC C → K. However, the distribution of A3G-induced mutations on HBV DNA during infection is not well characterized. To provide clarity, we obtained the HBV DNA sequences from HBV infected individuals with and without hepatocellular carcinoma (HCC and non-HCC, respectively), from the NCBI database, and calculated the r values of A3G-induced 5'CC C → K mutation prevalence in HBV DNA. A3G-induced mutations were weakly prevalent and mainly distributed in the plus strand of HBV DNA (r = 1.407). The mutations on the minus strand were weaker (r = .8189). There were A3G-induced mutation regions in the 1200 to 2000 nt region of the plus strand and the 1600 to 1500 nt region of the minus strand. There was no significant difference in the r values of A3G-induced mutations in HBV DNA between the HCC and non-HCC groups. However, the rvalue of the plus strand 2400 to 2800 nt regions of HCC derived HBV DNA (r = 4.2) was significantly higher than that of the same regions of non-HCC derived HBV DNA (r = 1.21). These findings clarify the weak prevalence and preferred plus-strand distribution of A3G-induced mutations on HBV DNA from HCC and non-HCC. These findings may provide valuable clues regarding the interaction mechanism between A3G and HBV DNA and inform HCC screening.

Evolutionary history of hepatitis B virus genotype H

Hepatitis B virus genotype H (HBV-H) molecular evolution was studied by comparing all published whole-genome sequences. Bayesian coalescent analysis was performed to estimate phylogenetic relationships, time to the most recent common ancestor (tMRCA), and viral population dynamics along the time. Phylogenetic tree demonstrated two main clades or lineages: HBV-H I (with sequences from Central and North America) and HBV-H II (with sequences from North and South America, and Asia). HBV-H II had more genome sequences (n = 26; 83.9%), including one specific subclade with all sequences outside of the Americas. Overall HBV-H tMRCA dated back to 1933 (95% highest posterior density interval [HPD 95%]: 1875-1957) with a very probable origin in Mexico and posterior dissemination to other American and Asian countries. The temporal analysis demonstrated that HBV-H I spread only in Mexico and the neighbor country of Nicaragua probably in the 1960s to the 1970s (1968; HPD 95%: 1908-1981), while HBV-II disseminated to other American and Asian countries around one decade later (1977; HPD 95%: 1925-1985). The phylogeographic analysis reinforced the Mexican origin of this genotype. The whole HBV-H population increased from the 1980s to the 2000s. In conclusion, HBV-H has two main lineages with a common origin in Mexico approximately nine decades ago.

Rapid, random-access, and quantification of hepatitis B virus using the Cepheid Xpert HBV viral load assay

BACKGROUND

Monitoring viral load (VL) is an essential part of the management of patients chronically infected with hepatitis B virus (HBV). The commercial HBV VL assays currently available are generally performed on high-throughput platforms for batch wise testing of plasma samples, with relatively long turn-around-times. Rapid VL testing could provide immediate input to clinical decision making.

METHODS

One hundred two stored plasma samples from 102 patients who were previously tested for HBV VL by the Cobas Ampliprep/Taqman or Cobas 4800 (Roche, Pleasanton, CA), were analyzed by the recently introduced Cepheid Xpert HBV Viral Load Assay. Thirty-one of the 102 samples were negative for HBV DNA and 71 out of 102 samples had a detectable VL. HBV DNA loads ranged from <20 to 5E8 IU/mL. HBV genotypes (A, B, C, D, E, and G) were known for 52 of the VL positive samples. Correlation of VL results between both assays was determined by the Pearson correlation coefficient (r2 ). The level of concordance was assessed using the Bland-Altman analysis.

RESULTS

HBV VLs correlated well between both assays, across all genotypes (Pearson correlation coefficient r2  = 0.987). Six samples exceeded a 0.5  log difference between assays. Bland-Altman analysis demonstrated a mean of the difference of -0.107 log and a standard deviation of 0.271 log.

CONCLUSION

High correlation was observed between the Roche Cobas HBV Viral Load tests and the Xpert HBV Viral Load Assay, thus enabling rapid, random access, and accurate HBV VL assessment.

Genetic diversity of hepatitis B virus in Yunnan, China: identification of novel subgenotype C17, an intergenotypic B/I recombinant, and B/C recombinants

Yunnan is considered to be a geographical hotspot for the introduction, mutation and recombination of several viruses in China. However, there are limited data regarding the genotypic profiles of hepatitis B virus (HBV) in this region. In this study, we characterized 206 HBV strains isolated from chronic hepatitis B patients in Yunnan, China. Initial genotyping based on 1.5 kb sequences revealed that genotype C was the most prevalent at 52.4 % (108/206), followed by genotype B at 30.6 % (63/206) and unclassified genotypes at 17.0 % (35/206). To characterize the 35 unclassified strains, 32 complete HBV genomes were amplified and analysed; 17 isolates were classified within a known subgenotype, 8 were classified as B/C recombinants, 1 was classified as a B/I recombinant and 6 constituted a potentially novel C subgenotype that we designated as C17, based on the characteristics of a monophyletic cluster, >4 % genetic distances, no significant evidence of recombination and no epidemiological link among individuals. Thus, multiple subgenotypes - namely B1, B2, B4, C1, C2, C3, C4, C8 and C17 - and two distinct intergenotypic recombinants exist in Yunnan, China, highlighting the complex and diverse distribution pattern of HBV genotypic profiles.

Predominance of HBV Genotype B and HDV Genotype 1 in Vietnamese Patients with Chronic Hepatitis

Hepatitis delta virus (HDV) coinfection will additionally aggravate the hepatitis B virus (HBV) burden in the coming decades, with an increase in HBV-related liver diseases. Between 2018 and 2019, a total of 205 HBV patients clinically characterized as chronic hepatitis B (CHB; n = 115), liver cirrhosis (LC; n = 21), and hepatocellular carcinoma (HCC; n = 69) were recruited. HBV surface antigen (HBsAg), antibodies against surface antigens (anti-HBs), and core antigens (anti-HBc) were determined by ELISA. The presence of hepatitis B viral DNA and hepatitis delta RNA was determined. Distinct HBV and HDV genotypes were phylogenetically reconstructed and vaccine escape mutations in the “a” determinant region of HBV were elucidated. All HBV patients were HbsAg positive, with 99% (n = 204) and 7% (n = 15) of them being positive for anti-HBc and anti-HBs, respectively. Anti-HBs positivity was higher among HCC (15%; n = 9) compared to CHB patients. The HBV-B genotype was predominant (65%; n = 134), followed by HBV-C (31%; n = 64), HBV-D, and HBV-G (3%; n = 7). HCC was observed frequently among young individuals with HBV-C genotypes. A low frequency (2%; n = 4) of vaccine escape mutations was observed. HBV-HDV coinfection was observed in 16% (n = 33) of patients with the predominant occurrence of the HDV-1 genotype. A significant association of genotypes with alanine aminotransferase (ALT) and aspartate aminotransferase (AST) enzyme levels was observed in HBV monoinfections. The prevalence of the HDV-1 genotype is high in Vietnam. No correlation was observed between HDV-HBV coinfections and disease progression when compared to HBV monoinfections.

Hepatitis B Virus: From Diagnosis to Treatment

Hepatitis B infection is still a global concern progressing as acute-chronic hepatitis, severe liver failure, and death. The infection is most widely transmitted from the infected mother to a child, with infected blood and body fluids. Pregnant women, adolescents, and all adults at high risk of chronic infection are recommended to be screened for hepatitis B infection. The initial analysis includes serological tests that allow differentiation of acute and chronic hepatitis. Molecular assays performed provide detection and quantification of viral DNA, genotyping, drug resistance, and precore/core mutation analysis to confirm infection and monitor disease progression in chronic hepatitis B patients. All patients with chronic hepatitis B should be treated with antiviral medications and regularly monitored for efficient treatment. The current treatment is based on nucleos(t)ide analogs and pegylated interferons that save lives by decreasing liver cancer death, liver transplant, slow or reverse the progression of liver disease as well as the virus infectivity.

Global Occurrence of Clinically Relevant Hepatitis B Virus Variants as Found by Analysis of Publicly Available Sequencing Data

Several viral factors impact the natural course of hepatitis B virus (HBV) infection, the sensitivity of diagnostic tests, or treatment response to interferon-α and nucleos(t)ide analogues. These factors include the viral genotype and serotype but also mutations affecting the HBV surface antigen, basal core promoter/pre-core region, or reverse transcriptase. However, a comprehensive overview of the distribution of HBV variants between HBV genotypes or different geographical locations is lacking. To address this, we performed an in silico analysis of publicly available HBV full-length genome sequences. We found that not only the serotype frequency but also the majority of clinically relevant mutations are primarily associated with specific genotypes. Distinct mutations enriched in certain world regions are not explained by the local genotype distribution. Two HBV variants previously identified to confer resistance to the nucleotide analogue tenofovir in vitro were not identified, questioning their translational relevance. In summary, our work elucidates the differences in the clinical manifestation of HBV infection observed between genotypes and geographical locations and furthermore helps identify suitable diagnostic tests and therapies.

Global and regional dispersal patterns of hepatitis B virus genotype E from and in Africa: A full-genome molecular analysis

Description of the spatial characteristics of viral dispersal is important in understanding the history of infections. Nine hepatitis B virus (HBV) genotypes (A-I), and a putative 10th genotype (J), with distinct geographical distribution, are recognized. In sub-Saharan Africa (sub)-genotypes A1, D3 and E circulate, with E predominating in western Africa (WA), where HBV is hyperendemic. The low genetic diversity of genotype E (HBV/E) suggests its recent emergence. Our aim was to study the dispersal of HBV/E using full-length, non-redundant and non-recombinant sequences available in public databases. HBV/E was confirmed, and the phylogeny reconstruction performed using maximum likelihood (ML) with bootstrapping. Phylogeographic analysis was conducted by reconstruction of ancestral states using the criterion of parsimony on the estimated ML phylogeny. 46.5% of HBV/E sequences were found within monophyletic clusters. Country-wise analysis revealed the existence of 50 regional clusters. Sequences from WA were located close to the root of the tree, indicating this region as the most probable origin of the HBV/E epidemic and expanded to other geographical regions, within and outside of Africa. A localized dispersal was observed with sequences from Nigeria and Guinea as compared to other WA countries. Based on the sequences available in the databases, the phylogenetic results suggest that European strains originated primarily from WA whereas a majority of American strains originated in Western Central Africa. The differences in regional dispersal patterns of HBV/E suggest limited cross-border transmissions because of restricted population movements.

Virological activity in treatment-naïve HBeAg-negative HBV-infected adult patients: A community-based study in Jiangsu, China

Nowadays most of the hepatitis B virus (HBV) infected population are adults, among which hepatitis B e antigen (HBeAg) negative infection occupied the largest proportion of HBV infection in China. HBeAg-negative patients are heterogeneous, and the corresponding interventions are different. Therefore, it is worth researching the infection characteristics of HBeAg-negative patients to help guide the interventions.A total of 11,738 treatment-naïve HBeAg-negative adult patients were randomly selected, and their demographic and medical history information were collected. The liver biochemistry, and HBV infection biomarkers including hepatitis B surface antigen (HBsAg), hepatitis B surface antibody (anti-HBs), HBeAg, hepatitis B e antibody (anti-HBe), hepatitis B core antibody (anti-HBc), and hepatitis B virus deoxyribonucleic acid (HBV-DNA) levels were tested. The infection characteristics and their influencing factors were explored.Sixty percent of the patients presented HBV-DNA-positive, of which 31.2% had HBV-DNA level higher than 2000 IU/mL, and 16.5% had HBV-DNA level higher than 20,000 IU/mL. HBV-DNA levels tended to increase along with the increasing of age, and the male patients had significant higher HBV-DNA levels than the female patients. Twenty-four percent of the patients had abnormal transaminase. The male patients were more vulnerable to abnormal transaminase (30.0%) than the female patients (18.4%). Fifty-five percent patients with HBV-DNA ≥20,000 IU/mL presented abnormal alanine aminotransferase (ALT) or aspartate transaminase (AST), which was significantly higher than that of patients with HBV-DNA levels below 20,000 IU/mL (19.0-21.7%). Multivariate logistic regression analyses revealed that the male patients and the patients with higher viral load had higher risk of having abnormal liver function.A considerable number of HBeAg-negative patients were virological active and had liver damage. It is necessary and urgent to carry out regular active interventions for the chronic HBV-infected patients.

Intra-host diversity of hepatitis B virus during mother-to-child transmission: the X gene may play a key role in virus survival in children after transmission

Mother-to-child transmission of hepatitis B virus (HBV) is the main route of transmission in Asia, and characterization of HBV quasispecies is needed to further understand virus evolution and adaptation. To understand changes in HBV during mother-to-child transmission, we enrolled nine pairs of mothers and children in the study, including a set of twins. Three groups were infected with HBV genotype C, and six groups were infected with HBV genotype B. The full-length HBV genome was amplified by PCR from serum samples before antiviral treatment, the whole viral genomes from each pair were sequenced, and the complexity and diversity of the quasispecies were analyzed. The entropy of transmitted HBV in children was found to be lower than their mothers, suggesting that there was a bottleneck effect during HBV transmission from the mother to the child. Selective evolution was shown by calculating πN and πS in the whole genomes, and the highest values were obtained for the X gene, which plays a role in viral replication and immune escape. All genotype C patients and only one genotype B pair had a πN/πS greater than 1 ratio, indicating that positive selection had occurred. In addition, quasispecies were found to be different between the twin children despite having the same mother, indicating that virus evolution is host-specific.

7-Deaza-7-fluoro modification confers on 4'-cyano-nucleosides potent activity against entecavir/adefovir-resistant HBV variants and favorable safety

We designed, synthesized and identified a novel nucleoside derivative, 4'-C-cyano-7-deaza-7-fluoro-2'-deoxyadenosine (CdFA), which exerts potent anti-HBV activity (IC50 ~26 nM) with favorable hepatocytotoxicity (CC50 ~56 μM). Southern blot analysis using wild-type HBV (HBVWT)-encoding-plasmid-transfected HepG2 cells revealed that CdFA efficiently suppresses the production of HBVWT (IC50 = 153.7 nM), entecavir (ETV)-resistant HBV carrying L180M/S202G/M204V substitutions (HBVETVR; IC50 = 373.2 nM), and adefovir dipivoxil (ADV)-resistant HBV carrying A181T/N236T substitutions (HBVADVR; IC50=192.6 nM), whereas ETV and ADV were less potent against HBVETVR and HBVADVR (IC50: >1,000 and 4,022.5 nM, respectively). Once-daily peroral administration of CdFA to human-liver-chimeric mice over 14 days (1 mg/kg/day) comparably blocked HBVWT and HBVETVR viremia by 0.7 and 1.2 logs, respectively, without significant changes in body-weight or serum human-albumin levels, although ETV only slightly suppressed HBVETVR viremia (CdFA vs ETV; p = 0.032). Molecular modeling suggested that ETV-TP has good nonpolar interactions with HBVWT reverse transcriptase (RTWT)'s Met204 and Asp205, while CdFA-TP fails to interact with Met204, in line with the relatively inferior activity against HBVWT of CdFA compared to ETV (IC50: 0.026 versus 0.003 nM). In contrast, the 4'-cyano of CdFA-TP forms good nonpolar contacts with RTWT's Leu180 and RTETVR's Met180, while ETV-TP loses interactions with RTETVR's Met180, explaining in part why ETV is less potent against HBVETVR than CdFA. The present results show that CdFA exerts potent activity against HBVWT, HBVETVR and HBVADVR with enhanced safety and that 7-deaza-7-fluoro modification confers potent activity against drug-resistant HBV variants and favorable safety, shedding light to further design more potent and safer anti-HBV nucleoside analogs.

PreS1 Mutations Alter the Large HBsAg Antigenicity of a Hepatitis B Virus Strain Isolated in Bangladesh

Mutations in the hepatitis B virus (HBV) genome can potentially lead to vaccination failure, diagnostic escape, and disease progression. However, there are no reports on viral gene expression and large hepatitis B surface antigen (HBsAg) antigenicity alterations due to mutations in HBV isolated from a Bangladeshi population. Here, we sequenced the full genome of the HBV isolated from a clinically infected patient in Bangladesh. The open reading frames (ORFs) (P, S, C, and X) of the isolated HBV strain were successfully amplified and cloned into a mammalian expression vector. The HBV isolate was identified as genotype C (sub-genotype C2), serotype adr, and evolutionarily related to strains isolated in Indonesia, Malaysia, and China. Clinically significant mutations, such as preS1 C2964A, reverse transcriptase domain I91L, and small HBsAg N3S, were identified. The viral P, S, C, and X genes were expressed in HEK-293T and HepG2 cells by transient transfection with a native subcellular distribution pattern analyzed by immunofluorescence assay. Western blotting of large HBsAg using preS1 antibody showed no staining, and preS1 ELISA showed a significant reduction in reactivity due to amino acid mutations. This mutated preS1 sequence has been identified in several Asian countries. To our knowledge, this is the first report investigating changes in large HBsAg antigenicity due to preS1 mutations.

Hepatitis B Virus: Alternative phylogenetic hypotheses and its impact on molecular evolution inferences

Characterizing molecular evolution patterns of the Hepatitis B Virus (HBV) is important for a better understanding of the natural history of this infection. However, several molecular evolution estimates are conditioned on tree topology. There is no consensus about the phylogenetic relationships of HBV genotypes, and different studies often find alternative topologies. While most studies consider HBV genotypes F and H as sister to all other human genotypes, a recent study suggested an alternative HBV phylogeny that indicates an accelerated substitution rate for HBV-F/H partially driven by positive selection. In this study, we evaluate the impact of alternative HBV topologies on inferences of HBV phylogeny, rate acceleration, and positive selection on the HBV-F/H branch. Our results indicate that under certain methodological approaches alternative HBV topologies are equally likely. Considering phylogenetic uncertainty, there is no evidence that HBV-F/H had an accelerated substitution rate, even though inferences of positive selection are robust to alternative background topologies. Our results further suggest that, under reasonable assumptions, HBV-F/H most likely represents the sister lineage to all other human/ape HBV genotypes. Understanding the full range of likely topologies will be crucial for elaborating, testing, and refining hypothesis about the evolutionary HBV origins in our species.

Detection of circulating hepatitis B virus immune escape and polymerase mutants among HBV-positive patients attending Institut Pasteur de Bangui, Central African Republic

Background

Previous studies in the Central African Republic (CAR) have reported the presence of hepatitis B virus (HBV) recombinant genotype E/D and a suspicion of immune escape mutants (IEMs), without further investigation into their impact on prevention and diagnosis. Consequently, this study investigated HBV mutations among hepatitis B surface antigen (HBsAg)-positive patients attending Institut Pasteur de Bangui in the CAR.

Methods

Sera from a total of 118 HBsAg-positive patients with no previous history of HBV treatment or vaccination at the Institut Pasteur de Bangui, were sampled between 2017 and 2019. Subsequently, the region spanning the surface and polymerase genes of HBV was amplified by PCR and sequenced. HBV sequences were genotyped/subgenotyped by phylogenetic analysis and serotyped based on predicted amino acid residues at positions s122, s127, s140, s159, and s160. They were then analyzed for HBV IEMs and polymerase mutations.

Results

The region spanning the surface and polymerase genes was successfully amplified and sequenced for 51 samples. Of the HBV sequences, 49 were genotype E and two were genotype A subgenotype A1; these were serotyped as ayw4 and ayw1, respectively. Potential IEMs sY100C, sA128V, and sM133T, and several polymerase mutants were identified.

Conclusions

This study raises awareness of the need for further studies to be conducted on a large scale to better understand HBV mutations for improved disease control and prevention strategies in the country.

Genetic Diversity of the Hepatitis B Virus Subgenotypes in Brazil

Hepatitis B virus (HBV) subgenotypes may be related to clinical outcomes and response to antiviral therapy. Most Brazilian studies on HBV subgenotypes are restricted to some regions and to specific population groups. Here, we provide an insight about genetic diversity of HBV subgenotypes in 321 serum samples from all five geographical regions, providing a representative overview of their circulation among chronic carriers. Overall, HBV/A1 was the most prevalent subgenotype, being found as the major one in all regions except in South Brazil. Among HBV/D samples, subgenotype D3 was the most prevalent, found in 51.5%, followed by D2 (27.3%) and D4 (21.2%). D2 and D3 were the most prevalent subgenotypes in South region, with high similarity with European strains. D4 was found in North and Northeast region and clustered with strains from Cape Verde and India. For HBV/F, the most frequent subgenotype was F2 (84.1%), followed by F4 (10.1%) and F1 (5.8%), closely related with strains from Venezuela, Argentina and Chile, respectively. Phylogeographic analyses were performed using an HBV full-length genome obtained from samples infected with genotypes rarely found in Brazil (B, C, and E). According to Bayesian inference, HBV/B2 and HBV/C2 were probably introduced in Brazil through China, and HBV/E from Guinea, all of them mostly linked to recent events of human migration. In conclusion, this study provided a comprehensive overview of the current circulation of HBV subgenotypes in Brazil. Our findings might contribute to a better understand of the dynamics of viral variants, to establish a permanent molecular surveillance on the introduction and dispersion patterns of new strains and, thus, to support public policies to control HBV dissemination in Brazil.

Genomic analysis of Hepatitis B virus and its association with disease manifestations in Bangladesh

The direct cytopathic effects of the hepatitis B virus (HBV) on subsequent liver damage are not fully understood in HBV-infected patients. However, associations between the prevalence of various HBV genotypes and the extent of liver damage have been reported from different parts of the world. The purpose of this study was to determine the distribution of HBV genotypes in patients with chronic HBV infection in Bangladesh, a country of 160 million people, of which approximately 3–6 million are chronically infected HBV patients. In addition, whole and partial genome sequencing of HBV was performed to evaluate the relationship between HBV mutations and genotypes. We found that 42% of the patients with low HBV DNA and normal levels of alanine aminotransferase (ALT) had HBV genotype D. In contrast, the HBV genotype C was dominant among patients with high HBV DNA levels (>2000 IU/ml) and elevated ALT and in patients with liver cirrhosis (LC) and hepatocellular carcinomas (HCC). Whole and partial genome sequences of HBV revealed that most patients with LC and HCC had HBV genotype C with mutations at the T1762/A1764 positions. It seems that Bangladesh represents a borderline country, situated within East Asia, which mainly consists of individuals with HBV genotypes B and C, whereas in the western parts of Asia, HBV genotypes A and D are prevalent. Bangladesh is, therefore, an excellent model for the comparison of the pathophysiology of three major HBV genotypes in a single population. The findings of this study suggest a possible association between HBV viral factors and the extent of liver damage in chronic HBV-infected patients.

Identification of hepatitis B virus genotype I in Thailand

The rare hepatitis B virus genotype I (HBV-I) classification includes complex A/G/C/U recombinants identified amongst the individuals from China, India, Laos, and Vietnam. Herein we report the first HBV-I specimen from Thailand, with detectable HBsAg despite a 10-amino-acid truncation. This HBV-I genome has a similar recombinant pattern to reference strains, including a C region that branches basal to references, suggesting a premodern era recombination event gave rise to HBV-I. With an average sequence divergence from other genotypes ranging from 7.66% (standard deviation [SD], 0.42%; C) to 14.27% (SD, 0.31%; H), this new genome supports the HBV-I classification as a unique genotype.

High Frequency of Either Altered Pre-Core StartCodon or Weakened Kozak Sequence in the CorePromoter Region in Hepatitis B Virus A1 Strainsfrom Rwanda

Hepatitis B virus (HBV) is endemic in Rwanda and is a major etiologic agent for chronic liver disease in the country. In a previous analysis of HBV strains from Rwanda, the S genes of most strains segregated into one single clade of subgenotype, A1. More than half (55%) of the anti-HBe positive individuals were viremic. In this study, 23 complete HBV genomes and the core promoter region (CP) from 18 additional strains were sequenced. Phylogenetic analysis of complete genomes confirmed that most Rwandan strain formed a single unique clade, within subgenotype A1. Strains from 17 of 22 (77%) anti-HBe positive HBV carriers had either mutated the precore start codon (9 strains with either CUG, ACG, UUG, or AAG) or mutations in the Kozak sequence preceding the pre-core start codon (8 strains). These mutually exclusive mutations were also identified in subgenotypes A1 (70/266; 26%), A2 (12/255; 5%), and A3 (26/49; 53%) sequences from the GenBank. The results showed that previous, rarely described HBV variants, expressing little or no HBeAg, are selected in anti-HBe positive subgenotype Al carriers from Rwanda and that mutations reducing HBeAg synthesis might be unique for a particular HBV clade, not just for a specific genotype or subgenotype.

Characterization of small genomic regions of the hepatitis B virus should be performed with more caution

BACKGROUND

Hepatitis B virus is a hepatotropic DNA virus that reproduces via an RNA intermediate. It can lead to an increased risk of serious liver diseases such as hepatocellular carcinoma and is a serious threat to public health. Currently, the HBV are designated based on greater than 8% nucleotide variation along the whole genome. The recombination of HBV is very common, a large majority of which are recombinants between 2 genotypes. The current work aims to characterize a suspected recombinant involving 3 genotypes.

METHODS

Fifty-seven HBV full-genome sequences were obtained from 57 patients co-infected with HBV and HIV-1 by amplification coupled with sequencing. JpHMM and RDP4 were used to perform recombination analysis respectively. The recombination results of a suspected 3-genotypic recombinant were further confirmed by both maximum likelihood phylogenetic tree and Mrbayes tree.

RESULTS

JpHMM recombination analysis clearly indicated one 3-genotypic HBV recombinant composing of B/C/D. The genotype assignments are supported by significant posterior probabilities. The subsequent phylogenetic analysis of sub-regions derived from inferred breakpoints led to a disagreement on the assignment of D segment. Investigating the conflict, further exploration by RDP4 and phylogenies revealed that the jpHMM-derived 3-genotypic recombinant is actually a B/C genotypic recombinant with C fragment spanning 1899 to 2295 (jpHMM) or 1821 to 2199 (RDP4).

CONCLUSIONS

The whole analysis indicated that (i) determination of small genomic regions should be performed with more caution, (ii) combinations of various recombination detection approaches conduce to obtain impartial results, and (iii) a unified system of nomenclature of HBV genotypes is necessary.

Correlations between serum hepatitis B surface antigen and hepatitis B core antibody titers and liver fibrosis in treatment-naïve CHB patients

BACKGROUND

Previous studies have revealed that quantitative hepatitis B surface antigen (HBsAg) or hepatitis B core antibody (qAnti-HBc) levels can be used as predictors of treatment response in both interferon-α and nucleoside analogue therapies. Few data have been published regarding the relationship between quantitative HBsAg or Anti-HBc levels and liver fibrosis stages in patients with chronic hepatitis B (CHB).

METHODS

We conducted a cross-sectional study of treatment-naïve CHB patients. A total of 624 CHB patients were recruited. We assessed the serum HBsAg and qAnti-HBc levels, HBV DNA levels, HBV genotypes, BCP/PC mutations, histological fibrosis staging by Scheuer classification.

RESULTS

In HBeAg (+) patients, the S0-1 subjects had significantly higher serum HBsAg and lower qAnti-HBc levels than the S2-4 subjects (both p < 0.001). A moderate inverse correlation was present between serum HBsAg levels and fibrosis scores (r = -0.381, p < 0.001), and a moderate positive correlation was found between qAnti-HBc levels and fibrosis scores (r = 0.408, p < 0.001). In the HBeAg (-) patients, the S0-1 subjects also had significantly lower qAnti-HBc levels than the S2-4 subjects (p < 0.001); however, no significant difference in the HBsAg levels was observed between the S0-1 and S2-4 subjects (p > 0.05). Serum qAnti-HBc levels showed a moderate positive correlation with fibrosis scores (r = 0.383, p < 0.001), while serum HBsAg levels exhibited a low inverse correlation with fibrosis scores (r = -0.171, p < 0.001). Multiple logistic regression analysis showed that the parameters for predicting significant fibrosis (S ≥ 2) included age, PLT, qAnti-HBc levels, HBV genotype and BCP/PC mutations in HBeAg (+) group, and age, PLT, qAnti-HBc levels in HBeAg (-) group (all p < 0.05). The AUC of qAnti-HBc levels associated with the diagnosis of significant fibrosis abnormalities in HBeAg (+) and HBeAg (-) patients were 0.734 (95%CI 0.689 to 0.778) and 0.707 (95%CI 0.612 to 0.801), respectively.

CONCLUSION

Our study found an association between high serum qAnti-HBc levels and significant fibrosis in both HBeAg (+) and HBeAg (-) treatment-naïve CHB patients. However, low serum HBsAg levels were correlated with moderate to severe fibrosis in HBeAg (+) subjects only.

Distribution of hepatitis B virus genotypes in Europe and clinical implications: a review

With an estimated 15 million infected persons in Europe, hepatitis B virus (HBV) infection is still one of the leading causes of chronic liver disease and associated mortality. The HBV infection prevalence in the general population depends on the region and ranges from 0.01% in Scandinavia to 10.3% in Kyrgyzstan. The prevalence of the 10 HBV genotypes (A-J) varies among different parts of the world, with genotypes A and D being most prevalent in Europe. Other HBV genotypes are mainly imported into Europe from other parts of the world and are rarely detected. HBV genotypes influence the clinical outcome of HBV infection, HBeAg seroconversion rates, and the frequency of mutations in the pre-core and core promoter regions. In addition, response rates to treatment with pegylated interferon alpha vary among HBV genotypes, whereas there is no influence of HBV genotypes on treatment response when using nucleoside/nucleotide analogues. Due to recent large-scale immigration to Europe, a change in HBV genotype distribution and the consequent clinical outcome of chronic hepatitis B may be expected in the near future.

Risk of hepatitis B virus reactivation in hepatitis B virus + hepatitis C virus-co-infected patients with compensated liver cirrhosis treated with ombitasvir, paritaprevir/r + dasabuvir + ribavirin

Hepatitis B virus may reactivate in patients with chronic hepatitis C treated with direct-acting antivirals. The aim of this study was to investigate the risk of hepatitis B virus (HBV) reactivation in HBV + hepatitis C virus (HCV)-co-infected patients with compensated liver cirrhosis treated with paritaprevir/ombitasvir/ritonavir, dasabuvir with ribavirin. We reviewed prospectively gathered data from a national cohort of 2070 hepatitis C virus patients with compensated liver cirrhosis who received reimbursed paritaprevir/ombitasvir/r, dasabuvir with ribavirin for 12 weeks from the Romanian National Health Agency during 2015-2016. Twenty-five patients in this cohort were HBs antigen positive (1.2%); 15 untreated with nucleotide analogues agreed to enter the study. These patients were followed up: ALT monthly, serology for HBV and DNA viral load at baseline, EOT and SVR at 12 weeks. Hepatitis B virus (HBV)-co-infected patients were all genotype 1b and 52% females, with a median age of 60 years (51 ÷ 74); 76% were pretreated with peginterferon + ribavirin; 72% were with severe necroinflammatory activity on FibroMax assessment; 40% presented comorbidities; and all were HBe antigen negative. Hepatitis C virus (HCV) SVR response rate was 100%. Hepatitis B virus (HBV)-DNA viral load was undetectable in 7/15 (47%) before therapy, and for the other 8 patients, it varied between below 20 and 867 IU/mL. Five patients (33%) presented virological reactivation (>2 log increase in HBV-DNA levels) during therapy. One patient presented with hepatitis associated with HBV reactivation, and two started anti-HBV therapy with entecavir. Hepatitis B virus (HBV) virological reactivation was present in 33% in our patients. Generally, HBV-DNA elevations were mild (<20 000 IU/mL); however, we report one case of hepatitis associated with HBV reactivation.

Analytical performance of the Hologic Aptima HBV Quant Assay and the COBAS Ampliprep/COBAS TaqMan HBV test v2.0 for the quantification of HBV DNA in plasma samples

BACKGROUND

Quantification of HBV DNA is used for initiating and monitoring antiviral treatment. Analytical test performance consequently impacts treatment decisions.

OBJECTIVES

To compare the analytical performance of the Aptima HBV Quant Assay (Aptima) and the COBAS Ampliprep/COBAS TaqMan HBV Test v2.0 (CAPCTMv2) for the quantification of HBV DNA in plasma samples.

STUDY DESIGN

The performance of the two tests was compared on 129 prospective plasma samples, and on 63 archived plasma samples of which 53 were genotyped. Linearity of the two assays was assessed on dilutions series of three clinical samples (Genotype B, C, and D).

RESULTS

Bland-Altman analysis of 120 clinical samples, which quantified in both tests, showed an average quantification bias (Aptima - CAPCTMv2) of -0.19 Log IU/mL (SD: 0.33 Log IU/mL). A single sample quantified more than three standard deviations higher in Aptima than in CAPCTMv2. Only minor differences were observed between genotype A (N = 4; average difference -0.01 Log IU/mL), B (N = 8; -0.13 Log IU/mL), C (N = 8; -0.31 Log IU/mL), D (N = 25; -0.22 Log IU/mL), and E (N = 7; -0.03 Log IU/mL). Deming regression showed that the two tests were excellently correlated (slope of the regression line 1.03; 95% CI: 0.998-1.068). Linearity of the tests was evaluated on dilution series and showed an excellent correlation of the two tests. Both tests were precise with %CV less than 3% for HBV DNA ≥3 Log IU/mL.

CONCLUSIONS

The Aptima and CAPCTMv2 tests are highly correlated, and both tests are useful for monitoring patients chronically infected with HBV.

Use of Blood Donor Screening to Monitor Prevalence of HIV and Hepatitis B and C Viruses, South Africa

Among 397,640 first-time blood donors screened in South Africa during 2012–2015, HIV prevalence was 1.13%, hepatitis B virus prevalence 0.66%, and hepatitis C virus prevalence 0.03%. Findings of note were a high HIV prevalence in Mpumalanga Province and the near absence of hepatitis C virus nationwide.

Hepatitis B and hepatitis D virus infections in the Central African Republic, twenty-five years after a fulminant hepatitis outbreak, indicate continuing spread in asymptomatic young adults

Hepatitis delta virus (HDV) increases morbidity in Hepatitis B virus (HBV)-infected patients. In the mid-eighties, an outbreak of HDV fulminant hepatitis (FH) in the Central African Republic (CAR) killed 88% of patients hospitalized in Bangui. We evaluated infections with HBV and HDV among students and pregnant women, 25 years after the fulminant hepatitis (FH) outbreak to determine (i) the prevalence of HBV and HDV infection in this population, (ii) the clinical risk factors for HBV and/or HDV infections, and (iii) to characterize and compare the strains from the FH outbreak in the 1980s to the 2010 HBV–HDV strains. We performed a cross sectional study with historical comparison on FH-stored samples (n = 179) from 159 patients and dried blood-spots from volunteer students and pregnant women groups (n = 2172). We analyzed risk factors potentially associated with HBV and HDV. Previous HBV infection (presence of anti-HBc) occurred in 345/1290 students (26.7%) and 186/870 pregnant women (21.4%)(p = 0.005), including 110 students (8.8%) and 71 pregnant women (8.2%), who were also HBsAg-positive (p = 0.824). HDV infection occurred more frequently in pregnant women (n = 13; 18.8%) than students (n = 6; 5.4%) (p = 0.010). Infection in childhood was probably the main HBV risk factor. The risk factors for HDV infection were age (p = 0.040), transfusion (p = 0.039), and a tendency for tattooing (p = 0.055) and absence of condom use (p = 0.049). HBV-E and HDV-1 were highly prevalent during both the FH outbreak and the 2010 screening project. For historical samples, due to storage conditions and despite several attempts, we could only obtain partial HDV amplification representing 25% of the full-length genome. The HDV-1 mid-eighties FH-strains did not form a specific clade and were affiliated to two different HDV-1 African subgenotypes, one of which also includes the 2010 HDV-1 strains. In the Central African Republic, these findings indicate a high prevalence of previous and current HBV-E and HDV-1 infections both in the mid-eighties fulminant hepatitis outbreak and among asymptomatic young adults in 2010, and reinforce the need for universal HBV vaccination and the prevention of HDV transmission among HBsAg-positive patients through blood or sexual routes.

In the Central African Republic (CAR), due to 20 years of conflict, the health system has been disorganized. This could contribute to maintenance of high transmission levels of Hepatitis B Virus (HBV) and its satellite Hepatitis Delta Virus (HDV). This work studies the evolution of both infections 25 years after a fulminant hepatitis (FH) outbreak occurring in the mid-1980s associated with HDV superinfection. In young asymptomatic adults, the results show that both HBV and HDV were still actively circulating in CAR in 2010. Indeed, more than one third of HBV-infected individuals were chronic HBV carriers. Furthermore, HDV infection could be spreading among 10% of them through blood and sexual transmission. The past FH outbreak and contemporary infections were both associated with heterogeneous HDV-1 strains, combined with HBV-E. Vaccination against HBV was uncommon among pregnant women and students, even among medical students. The study constitutes warning signals to help CAR health-care reconstruction and underlines the importance of HBV vaccination. The high level of HBV infection creates a background for HDV superinfection. Neonatal HBV vaccination is needed, together with vaccination of unprotected populations. Awareness of health authorities as well as the general public would help reduce HBV and HDV infections.

Extended duration of treatment with peginterferon alfa-2a in patients with chronic hepatitis B, HBeAg-negative and E genotype: A retrospective analysis

An alternative approach in the treatment of chronic hepatitis B (CHB) with pegylated (PEG)-interferon (IFN) is the prolonged course to 96 weeks of therapy, with higher sustained response (SR) than patients treated for 48 weeks. This result was confirmed in patients with CHB and D genotype, while no data are currently available about the prolonged course of PEG-IFN in E genotype. This retrospective analysis reported the role of different treatment duration of PEG-IFN on the SR in patients affected by CHB and E genotype. A total of 86 subjects with CHB and E genotype were considered in this analysis; different treatment durations were: 48 weeks (control group, 41 patients), 72 weeks (25 patients), and 96 weeks (19 patients). Treatment effectiveness was evaluated with sustained response (SR) and serological response. SR was significantly higher in patients who underwent PEG-IFN for 96 weeks in comparison to 48 weeks: 14.6% versus 26.3% (P = 0.016). HBsAg loss rate was 5.3% in patients treated for 96 weeks and 2.4% in the control group. In the multivariate analysis only the 72 and 96 weeks of therapy (OR 2.335, 95% CI 1.550-4.578; P = 0.020 and (OR 3.890, 95% CI 1.991-10.961; P = 0003) were predictive of SR. The extended duration of PEG-IFN course in patients with CHB and genotype E is a promising approach to increase the SR and HBsAg clearance.

Molecular evolution and phylodynamics of hepatitis B virus infection circulating in Iran

Previous local and national Iranian publications indicate that all Iranian hepatitis B virus (HBV) strains belong to HBV genotype D. The aim of this study was to analyze the evolutionary history of HBV infection in Iran for the first time, based on an intensive phylodynamic study. The evolutionary parameters, time to most recent common ancestor (tMRCA), and the population dynamics of infections were investigated using the Bayesian Monte Carlo Markov chain (BMCMC). The effective sample size (ESS) and sampling convergence were then monitored. After sampling from the posterior distribution of the nucleotide substitution rate and other evolutionary parameters, the point estimations (median) of these parameters were obtained. All Iranian HBV isolates were of genotype D, sub-type ayw2. The origin of HBV is regarded as having evolved first on the eastern border, before moving westward, where Isfahan province then hosted the virus. Afterwards, the virus moved to the south and west of the country. The tMRCA of HBV in Iran was estimated to be around 1894, with a 95% credible interval between the years 1701 and 1957. The effective number of infections increased exponentially from around 1925 to 1960. Conversely, from around 1992 onwards, the effective number of HBV infections has decreased at a very high rate. Phylodynamic inference clearly demonstrates a unique homogenous pattern of HBV genotype D compatible with a steady configuration of the decreased effective number of infections in the population in recent years, possibly due to the implementation of blood donation screening and vaccination programs. Adequate molecular epidemiology databases for HBV are crucial for infection prevention and treatment programs.

Phylogenetic analysis reveals three distinct epidemiological profiles in Dutch and Flemish blood donors with hepatitis B virus infection

During 2006-2016, hepatitis B virus (HBV) was detected in nearly 400 blood donors in the Netherlands and Flanders. Donor demographics and self-reported risk factors as disclosed during the donor exit interview were compared to HBV phylogenies of donor and reference sequences. First-time donors with chronic HBV-infection were often immigrants (67%) infected with genetically highly diverse strains of genotypes A (32%), B (8%), C (6%), D (53%) and E to H (1%). Each subtype was strongly associated with donor ethnicity. In contrast, 57/62 (93%) of acute/recent HBV infections occurred among indigenous donors, of whom 67% was infected with one specific widely circulating epidemic HBV-A2 lineage. HBV typing identified three distinct epidemiological profiles: the import of chronic HBV infections through migration, longstanding transmission of non-epidemic HBV-A2 strains within western-Europe, and the active transmission of one epidemic HBV-A2 strain most likely fueled by sexual risk behavior.

Genetic and phylogenic characterization of hepatitis B virus in the eastern part of the Democratic Republic of Congo

Hepatitis B virus (HBV) genotypes show a distinctive geographical distribution worldwide and genotypes A, D, and E are the most frequently found in Africa. There are only limited studies on HBV genotype distribution in Democratic Republic of Congo (DRC), all done in the western part showing a vast majority of genotype E. In our study, HBV strains from South Kivu, an eastern province of the DRC, were analyzed. Sequencing of 41 serum samples from HBV infected patients revealed strains of genotype A in 40/41 (97.6%) and genotype E in 1/41 (2.4%). The phylogenetic analysis showed that nearly all genotypes A (38/40) were closely related to A1 subgenotype strains found in Rwanda, Haiti, and Martinique while only two strains attached to the A2 subgenotype cluster were isolated. The remaining genotype E case was linked to the western African E crescent. Only the I169T nucleotide substitution was observed in two genotype A samples. In conclusion, the genotype A seems to be the most predominant genotype in eastern DRC with the majority belonging to the Afro-Asian subgenotype (A1). This contrasts with the western part of DRC where genotype E is predominant. These results support the hypothesis of an East-West genotypic demarcation.

Deep sequencing analysis of quasispecies in the HBV pre-S region and its association with hepatocellular carcinoma

BACKGROUND

The association between the evolution of hepatitis B virus (HBV) quasispecies and the development of hepatocellular carcinoma (HCC) is unknown.

METHODS

We used deep sequencing to examine the dynamics of HBV quasispecies and their relationship to HCC development. Thirty-two chronic hepatitis B (CHB) patients with HCC (HCC group) and 32 matched CHB patients without HCC (controls) were recruited. Fourteen patients from each group had serial sera available up to 9 years before the time of the present study. Deep sequencing of the HBV pre-S regions was performed. HBV quasispecies complexity, diversity, and intrapatient prevalence of pre-S deletions/mutations were analyzed.

RESULTS

Compared with control patients, HCC patients had a significant greater quasispecies complexity (p = 0.04 at the nucleotide level), greater diversity (p = 0.004 and 0.009 at the nucleotide level and the amino acid level respectively), and a trend of greater complexity at the amino acid level (p = 0.065). HCC patients had a higher intrapatient prevalence of pre-S deletions and point mutations (at codons 4, 27, and 167) compared with the control patients (all p < 0.05). Longitudinal observation in the sera of 14 HCC patients showed that quasispecies complexity (p = 0.027 and 0.024 at the nucleotide level and the amino acid level respectively) and diversity (p = 0.035 and 0.031 at the nucleotide level and the amino acid level respectively) increased as the disease progressed to HCC.

CONCLUSIONS

Increased HBV quasispecies complexity and diversity in the pre-S region, probably reflecting enhanced virus-host interplay, was associated with disease progression from CHB to HCC.

Identification and comparative analysis of hepatitis B virus genotype D/E recombinants in Africa

Globally, there are approximately 240 million people chronically infected with hepatitis B virus (HBV)-a major cause of hepatocellular carcinoma. Ten different HBV genotypes (A-J) have been identified with distinct geographic distributions. Novel variants generated by recombination between different HBV genotypes have been documented worldwide and represent an important element of genetic variability with possible clinical implications. Here, the complete genome sequence of an HBV genotype D/E recombinant from Ghana is reported. The full-length sequence was obtained using rolling circle amplification followed by PCR and sequenced using next-generation sequencing (NGS). A consensus sequence was extracted from the NGS data and underwent phylogenetic analysis to determine genotype, as well as the recombination pattern. Subsequently, the sequence was compared to recombinants described previously in Africa. Based on MCMC phylogenetic analysis, SimPlot recombination analyses, and intragroup genetic distance, the isolate 007N full-length genome is unique compared to other reported D/E recombinants in Africa.

Clustering infection of hepatitis B virus genotype B4 among residents in Vietnam, and its genomic characters both intra- and extra-family

Vietnam has a high rate of hepatitis B virus (HBV) infection and a high mortality rate from hepatocellular carcinoma. We performed a detailed genetic analysis of 48 residents and four families from Binh Thuan Province, a southern coastal area of Vietnam. The route of infection and genomic characteristics related to hepatocellular carcinoma (HCC) were studied in HBV spread among carriers that we detected in our previous hepatitis survey. The HBV genotype was B4 in 91.7% and C1 in 8.3% of the cases. The intra-family’s HBV sequence homology was high at 96.8–99.4%. However, it was also high at 99.4–99.8% among residents of the same age and sex as family members. In addition, full genome analysis was performed in 21 cases. The core region of all 20 isolates with genotype B4 was a recombinant of genotype C, and pre-S deletion was found in 20% of cases. The promoter mutation G1613A was found in 13.6% of cases, and a 24 bp insertion from nt1673 in the X region was found in 6.3% of cases. The phylogenetic tree and homology analysis of the HBV full genome suggested the probability and its possibility of horizontal transmission not only within families nor vertical transmission but within cohorts of the same generation in the population. Moreover, the HBV genotype B4 isolates were found not only to be recombinants of genotype C, which results in a high cancer risk, but also to have other risk of HCC, pre-S deletions, the G1613A mutation, and X region insertions corresponding to the promoter. These genomic characters were suggested to be one of the factors to explain the high HCC mortality rate in Vietnam.

Hepatitis B genotypes and surface antigen mutants present in Pakistani blood donors

BACKGROUND

The prevalence of chronic Hepatitis B Virus (HBV) infection is 2-4% in the Pakistani population, defining Pakistan as an intermediate prevalence country. In this study, hepatitis B surface antigen (HBsAg) reactive blood donations were screened using a combination of serological and molecular methods to identify immune escape HBV mutant strains and to determine the HBV genotypes and subtypes present in Pakistan.

METHODS

Blood donations were collected at the Armed Forces Institute of Transfusion (AFIT) located in northern Pakistan and the Hussaini Blood Bank (HBB) located in the south. From 2009 to 2013 a total of 706,575 donations were screened with 2.04% (14,409) HBsAg reactive. A total of 2055 HBsAg reactive specimens, were collected and screened using a monoclonal antibody based research assay to identify immune escape mutants followed by PCR amplification and DNA sequencing to identify the mutation present. DNA sequences obtained from 192 specimens, including mutant candidates and wild type strains, were analyzed for escape mutations, genotype, and HBsAg subtype.

RESULTS

Mutations were identified in approximately 14% of HBsAg reactive donations. Mutations at HBsAg amino acid positions 143-145 are the most common (46%) with the mutation serine 143 to leucine the most frequently occurring change (28%). While regional differences were observed, the most prevalent HBV strains are subgenotypes of D with subgenotype D1/subtype ayw2 accounting for the majority of infections; 90.2% at AFIT and 52.5% at HBB.

CONCLUSIONS

The high frequency of immune escape HBV mutants in HBV infected Pakistani blood donors highlights the need for more studies into the prevalence of escape mutants. Differences between vaccinated and unvaccinated populations, the correlation of escape mutant frequency with genotype, and impact of escape mutations in different genotype backgrounds on the performance of commercially available HBsAg assays represent avenues for further investigation.

Sequence analysis and functional characterization of full-length hepatitis B virus genomes from Korean cirrhotic patients with or without liver cancer

This study aimed to identify and characterize mutations in the hepatitis B virus (HBV) genome associated with advanced liver diseases. The 3.2-kb HBV genome of the C2 subgenotype was amplified from sera of 18 cirrhotic Korean patients with (10) or without (8) hepatocellular carcinoma (HCC), and two clones per patient were characterized by transient transfection experiments in human hepatoma cells. While A1762T/G1764A core promoter mutations were highly prevalent in both groups, the G1896A precore mutation to abolish hepatitis B e antigen (HBeAg) expression was more common in HCC clones (55% vs. 20%). High replication capacity was mostly found in HCC clones and associated with core promoter mutations, whereas more non-HCC clones harbored a nonfunctional core gene (34% vs. 8%). Large in-frame deletions in the preS region were found in 60% of HCC clones and 38% of non-HCC clones. They removed the first 11 residues of large envelope protein or impaired small envelope protein expression, or deleted a neutralizing epitope in the preS2 domain. Additional point mutations prevented middle envelope protein expression, or caused nonsense mutations in the preS or S region to truncate large and/or small envelope protein. Consequently, many clones were unable to express or secrete hepatitis B surface antigen (HBsAg). In conclusion, mutations associated with the advanced stage of chronic HBV infection are complex and diverse. Host immune pressure most likely selected for mutations in the HBV genome to abolish or reduce HBeAg or HBsAg production, to enhance genome replication, or to escape neutralizing antibodies. Some of these mutations may contribute to liver cirrhosis or HCC development.

Comparative characterization of hepatitis B virus surface antigen derived from different hepatitis B virus genotypes

For human hepatitis B virus eight distinct and two candidate genotypes are described. These genotypes differ with respect to geographic distribution, molecular virology and virus-associated pathogenesis. Comparative analysis of HBV genotypes revealed, with exception of HBV/G that shows impaired HBsAg release, that no fundamental disparities between genotypes exist regarding glycosylation, subcellular distribution, release of HBsAg and formation of subviral particles. However, there are distinctions regarding the proportion of L to M to S HBs proteins detected intra- and extracellularly for different genotypes. 2D electrophoresis revealed different posttranslational modification patterns for LHBs. In light of the relevance of HBsAg as diagnostic marker, detectability of purified recombinant HBsAg of various genotypes by HBsAg-specific detection systems licensed in Europe was investigated, showing similar sensitivities for genotypes included in this analysis. These data indicate that recombinant HBsAg reproducibly purified following a defined protocol might be used as an alternative to reference materials currently established.

Analyses of the Genetic Diversities and Mutations of the Hepatitis B Virus Genome BCP/Pre C Region

We wished to study the genetic diversities and mutations of the basic core promoter (BCP) and pre-C region of the hepatitis B virus (HBV) in liver-cancer tissues. One hundred and ninety-two tissue samples were collected from patients suffering from hepatocellular carcinoma (HCC) and HBV infection in 2015 in Xijing Hospital. Twenty-one cases were selected, of which direct sequencing of the polymerase chain reaction (PCR)-amplified products of BCP/pre-C region was unsuccessful. Cloning and sequencing allowed the DNA sequences of the BCP/pre-C region to be analyzed. Sequencing showed infection with mixed mutants of HBV in 37. 89% of HBV-positive HCC patients, and that HBV DNA in each sample contained 2 ~ 11 types of mutations.. The mutation rate of deletion and insertion was 80. 95%. Other mutations in descending order by mutation rate were a: A1762T/G1764A combined mutation (90. 48%); G1756C/T1803A/A(1757 ~ 1765)/A (1824 ~ 1832) combined mutation (80. 95%); T1753C/A1762T/ G1764A combined mutation (57. 14%); A1762T/G1764A/G1896A combined mutation (42. 86%); G1756C/Δ(1757~176.5) combined mutation,(28. 57%); T1753C/A1762T/G1764A/G1896A combined mutation (23. 81%). The sequencing failure of PCR products may have been correlated directly with the deletion and insertion mutations of HBV DNA. These findings lay the foundation for further studies on HBV mutations, persistent infection, and the mechanism of personalized medicine.

Analysis on Genotype Distribution and Mutation of Major Hydroponic Region of Hepatitis B Virus in Henan Province

To understand the genotype and the mutation of amino acid (aa) in the major hydrophilic region (MHR) of hepatitis B virus(HBV). The serum samples were collected from the surveillance of HBV among population in Henan in 2012. The S gene of HBV was amplified and sequenced. The acid amino sequences were analyzed with Mega6. 0 software. A total of 50 sequences of HBV S gene were contained, including 8 sequences of genotype B(16. 0%) and 42 sequences of genotype C (84. 0%). The main serotype of HBV among Henan population was adrq+ (84. 0%) . The mutation rate of T1261 was the highest (14. 0%). The overall prevalence of mutant strain of MHR was 24. 0% (12/50), and it was 37. 5% (3/8) for genotype B,21. 4% (9/42) for genotype C. HBV genotype C was predominant in Henan,followed by genotype B. The adrq+ serotype was predominant followed by adw2. The mutation of amino acid in,MHR of HBV was detected in this study. It is necessary to strengthen the surveillance for HBV mutation to provide accurate information during immunization process and HBIG therapy.

Occult HBV Infection in Immunized Neonates Born to HBsAg-Positive Mothers: A Prospective and Follow-Up Study

Objective

Occult HBV infection (OBI) has been reported in infants born to HBsAg-positive mothers despite immunization. This study aims to determine the maintenance of this status in a prospective birth cohort.

Methods

A total of 158 neonates born to HBsAg-positive mothers were enrolled. All received passive-active immunization against HBV according to a 0-1-6 schedule. Sera were collected at 7 months of age. Those diagnosed with OBI were serially followed up at 12, 24 and 36 months of age. HBV serological markers were determined by Abbott i2000 system. HBV DNA was quantitated by Abbott m2000 system. Standard PCR followed by direct sequencing were applied for mother-child HBV pairs. Homology and phylogenetic comparisons were done by BLAST and Mega 5.

Results

All the 158 neonates were HBsAg-negative and anti-HBs-positive at 7 months of age, and 32 (20.3%) of them were diagnosed with OBI, with a median HBV DNA level of 1.97 (1.20–3.71) log IU/mL. Of them, HBV DNA was positive in 25.0%, 21.9% and 7.7% at 12, 24 and 36 months of age, respectively. HBV DNA disappeared at one of the follow-up points in 31 neonates, however, rebounded to low levels in 6 of them thereafter. HBV DNA persisted at low levels during follow-ups in the other one neonate apart from the above 31. All remained negative for HBsAg. Only two (6.3%) neonates were positive for anti-HBc after 24 months of age. HBV showed close homology and phylogenetic relationships for mother-child pairs. S-escape mutant, G145R, was not discovered. The first vaccine dose within 6 hours of birth significantly reduced the occurrence of OBI (59.4% vs. 83.3%, p = 0.003).

Conclusions

HBV may be controlled in immunized neonates of HBsAg-positive mothers, after being diagnosed with OBI. Timely vaccination against HBV may provide the utmost protection. Long-term and close monitorings are needed.

Characterization of Novel Hepatitis B Virus PreS/S-Gene Mutations in a Patient with Occult Hepatitis B Virus Infection

Objective

The impact of hepatitis B virus (HBV) preS/S-gene mutations on occult HBV infection (OBI) is not fully understood. This study characterized multiple novel HBV preS/S-gene mutants obtained from an OBI patient.

Methods

PreS/S-gene mutants were analyzed by clonal sequencing. Viral replication and expression were analyzed by transfecting HBV genomic recombinants into HepG2 cells.

Results

Twenty-one preS/S-gene mutants were cloned from four sequential serum samples, including 13 mutants that were not previously documented: (1) sI/T126V+sG145R; (2) preS1 nt 3014−3198 deletion; (3) preS1 nt 3046−3177 deletion; (4) preS1 nt 3046−3177 deletion+s115−116 “INGTST” insertion; (5) preS1 nt 3046−3177 deletion+s115−116 “INGTST” insertion+sG145R; (6) preS1 nt 3115−3123 deletion+sQ129N; (7) preS1 nt 3115−3123 deletion+s126−127 “RPCMNCTI” insertion; (8) s115−116 “INGTST” insertion; (9) s115−116 “INGTST” insertion+sG145R; (10) s126−127 “RPCMNCTI” insertion; (11) preS1 nt 2848−2862 deletion+preS2 initiation codon M→I; (12) s122−123 “KSTGLCK” insertion+sQ129N; and (13) preS2 initiation codon M→I+s131−133TSM→NST. The proportion of preS1 nt 3046−3177 deletion and preS2 initiation codon M→I+s131−133TSM→NST mutants increased in the viral pool with prolonged disease. The 13 novel OBI-related mutants showed a 51.2−99.9% decrease in HBsAg levels compared with that of the wild type. Additional N-glycosylation-associated mutations, sQ129N and s131−133TSM→NST, but not s126−127 “RPCMNCTI,” greatly attenuated anti-HBs binding to HBsAg. Compared with the wild type, replication and surface antigen promoter II activity of the preS1 nt 3046−3177 deletion mutant decreased by 43.3% and 97.0%, respectively.

Conclusion

PreS/S-gene mutations may play coordinated roles in the presentation of OBI and might be associated with disease progression. This has implications for HBV diagnosis and vaccine improvement.

[Whole-sequence Analyses for 12 HBV C/D Recombinants from a Population in Tibet (China)]

We wished to undertake molecular genetic typing and evaluate recombinants of the hepatitis-B virus (HBV) in Tibet (China). Multistage random sampling was used to collect HBsAg-positive samples. Nested polymerase chain reactions were used to amplify the whole sequence of the HBV. DNAstar, MEGA6 and SimPlot were used to assemble sequences, create phylogenetic trees, and undertake recombination analyses. Twelve whole sequences of the HBV of a Tibetan population were collected using these methods. Results showed that all 12 strains were C/D recombinants. Nine of the recombinations were at nt750, and the other three at nt1526. Therefore, the 12 strains could be divided into two types of recombinants: C/Da and C/Db. Analyses of the sequence of the whole genome revealed that the 12 strains belonged to genotype C, and that the nucleotide distance was > 4% between the 12 strains and sub-genotypes C1 to C15 in Genbank. The most likely sub-genotype was C1. Individuals with C/Da were from central and northern Tibet (e.g., Lasa, Linzhi, Ali) and those with C/Db recombinants were from Shannan in southern Tibet. These data suggest that the two types of recombinants had a good distribution in Tibet. Also, they can provide important information for studies on HBV recombination, gene features, virus evolution, as well as the control and prevention of HBV infection in Tibet.

[SPECIES COMPOSITION OF INFECTIOUS FACTORS THAT CAUSE THE REACTIVE ARTHRITIS DEVELOPMENT AND THEIR EFFECT ON ARGINASE-NO-SYNTHASE REGULATORY SYSTEM OF PERIPHERAL BLOOD LYMPHOCYTES]

The own observations results of urogenital, gastrointestinal and nasopharyngeal infectious factors that cause the development of reactive arthritis (PeA) are being presented. The greatest contribution to the development of this disease make Chlamidia trachomatis (36%), Streptococcus haemolyticus (pyogenes) (19%) and hepatitis viruses B and C (10%). As a result of the research a number of kinetic parameters of arginase and NO-synthase reactions in peripheral blood lymphocytes of patients with reactive arthritis was identified. The authentic increase of arginase activity in 3.3 times and eNO-synthase activity decrease by 1,9 times in peripheral blood lymphocytes of patients with PeA, compared to practically healthy donors were determined. Increased activity of arginase and iNO-synthase of lymphocytes indicates changes in immune cells functional activity, which may be due to impaired metabolic and regulatory processes in these cells caused by a bacterial or viral infection.

Phylogenetic Analysis of Hepatitis B Virus Genotypes Circulating in Different Risk Groups of Panama, Evidence of the Introduction of Genotype A2 in the Country

The Hepatitis B Virus (HBV) can cause acute or chronic infection it is also associated with the development of liver cancer, thousands of new infections occur on a yearly basis, and many of these cases are located in certain areas of the Caribbean and Latin America. In these areas, the HBV prevalence is still high which makes this virus a serious public health concern to the entire region. Studies performed in Panama suggest a complex pattern in the distribution of HBV among the country’s different risk groups. We use phylogenetic analysis in order to determine which HBV genotypes were circulating in these specific groups; for this we used a fragment of the PreS2/2 region of the HBV genome. Subsequently whole HBV genome sequences were used for Bayesian analysis of phylodynamics and phylogeography. Two main genotypes were found: genotype A (54.5%) and genotype F (45.5%). There was a difference in the distribution of genotypes according to risk groups: 72.9% of high risk groups were associated to genotype A, and 55.0% of samples of genotype F were associated to the low risk group (p<0.002). The Bayesian analysis of phylogeny-traits association revealed a statistically significant geographical association (p<0.0001) with both genotypes and different regions of the country. The Bayesian time of most recent common ancestor analysis (tMRCA) revealed a recent tMRCA for genotype A2 circulating in Panama (1997, 95% HPD: 1986—2005), when it is compared with Panamanian genotype F1c sequences (1930, 95% HPD: 1810 – 2005). These results suggest a possible change in the distribution of HBV genotypes in Panama and Latin America as a whole. They also serve to encourage the implementation of vaccination programs in high-risk groups, in order to prevent an increase in the number of new HBV cases in Latin America and worldwide.

Genetic Diversity of the Hepatitis B Virus Strains in Cuba: Absence of West-African Genotypes despite the Transatlantic Slave Trade

Cuba is an HBsAg low-prevalence country with a high coverage of anti-hepatitis B vaccine. Its population is essentially the result of the population mix of Spanish descendants and former African slaves. Information about genetic characteristics of hepatitis B virus (HBV) strains circulating in the country is scarce. The HBV genotypes/subgenotypes, serotypes, mixed infections, and S gene mutations of 172 Cuban HBsAg and HBV-DNA positive patients were determined by direct sequencing and phylogenetic analysis. Phylogenetic analysis of HBV S gene sequences showed a predominance of genotype A (92.4%), subgenotype A2 (84.9%) and A1 (7.6%). Genotype D (7.0%) and subgenotype C1 (0.6%) were also detected but typical (sub)genotypes of contemporary West-Africa (E, A3) were conspicuously absent. All genotype A, D, and C strains exhibited sequence characteristics of the adw2, ayw2, and adrq serotypes, respectively. Thirty-three (19.1%) patients showed single, double, or multiple point mutations inside the Major Hydrophilic domain associated with vaccine escape; eighteen (10.5%) patients had mutations in the T-cell epitope (amino acids 28-51), and there were another 111 point mutations downstream of the S gene. One patient had an HBV A1/A2 mixed infection. This first genetic study of Cuban HBV viruses revealed only strains that were interspersed with strains from particularly Europe, America, and Asia. The absence of genotype E supports previous hypotheses about an only recent introduction of this genotype into the general population in Africa. The presence of well-known vaccine escape (3.5%) and viral resistance mutants (2.9%) warrants strain surveillance to guide vaccination and treatment strategies.

The impact of viral molecular diversity on the clinical presentation and outcome of acute hepatitis B in Italy

The incidence of acute hepatitis B (AHB) in Italy, mostly sustained by hepatitis B virus (HBV) genotype D, has significantly decreased in the last two decades, but the new HBV strains introduced through immigrant populations from countries with a higher endemicity constitute a new emergency. HBV-genotype D still predominates in AHB, the subgenotype D3 being associated with parenteral transmission, and the recently emerging subgenotype A2 with unsafe sexual intercourse. Genetic, phylogenetic and evolutional analyses are powerful tools for countries with high immigration rates to monitor new viral strains with different aggressiveness and a different response to therapy.

[Clinical and pathological differences between children with various genotypes of hepatitis B virus-associated glomerulonephritis]

OBJECTIVE

To compare the clinical and pathological features between children with various genotypes of hepatitis B virus-associated glomerulonephritis (HBV-GN).

METHODS

Forty-one children with HBV-GN concurrently undergoing liver and renal biopsy were randomly selected. Serum specimens were collected for genotyping and hepatitis B virus (HBV) cccDNA assay. The clinical, pathological, and HBV cccDNA differences between HBV-GN children of various genotypes were analyzed.

RESULTS

Among the 41 HBV-GN children, 29 (71%) were genotype C, 10 (24%) were genotype B, and 2 (5%) were genotype B/C. The incidence rates of hematuria, albuminuria, complement 3 decrease, alanine transaminase increase, and renal insufficiency in the genotype C group were significantly higher than those in the genotype B group (P<0.05). Similarly, the HBV cccDNA positive rate was significantly higher in the genotype C group than that in the genotype B group. No difference was observed in the distribution of pathological types of renal tissues betwee the two geonotype groups. There were no significant differences in the degrees of hepatic inflammation and fibrosis between the two groups.

CONCLUSIONS

Mainly genotypes C and B occur in children with HBV-GN and the former genotype is dominant. The clinical symptoms of patients with genotype C are more serious than those with genotype B. However, there is no difference in the pathological features between them.

GENOMIC ANALYSIS OF HEPATITIS B VIRUS STRAINS INFECTING ROMANIAN PATIENTS

Chronic hepatitis B is widespread and represents an important cause of morbidity and mortality due to the evolution to cirrhosis and hepatocellular carcinoma. This study was designed to improve the national laboratory surveillance of hepatitis B virus (HBV) infection, focusing on genomic analysis of isolates from Romanian patients. Sera from ten patients with HBV were collected and analyzed. Phylogenetic analysis was conducted on a DNA fragment spanning almost the entire genome. The occurrence of mutations was assessed for each open reading frame in the viral genome. Phylogenetic analysis revealed five isolates belonging to genotype A (subgenotype A2) and other five clustering with genotype D strains (subgenotype D1). Two patients treated with lamivudine were found to carry isolates harboring rtM204V lamivudine resistance mutation. An HBV isolate displaying a lamivudine complex resistance pattern, rtM204I in conjunction with rtL180M and rtA200V, was found in a lamivudine naïve patient. All samples harbored sA105P substitution, usually found in HBIg therapy escape isolates. Three of the studied strains were simultaneously displaying T1753, T1762 and A1764 mutations which in vitro induce enhanced genome replication and reduction of HBeAg expression. The sequence obtained from a patient with decompensated liver cirrhosis presents a novel type of insertion consisting of nine nucleotides between positions 260 and 261 in the X gene. Despite the small number of samples, our findings suggest the need to determine the drug resistance pattern for each patient before taking a therapeutic decision and also highlight the necessity of knowing the real level of drug resistance among HBV strains circulating in Romania.