Genotype determination in Moroccan hepatitis B chronic carriers

Whole genome analysis of hepatitis B virus before and during long-term therapy in chronic infected patients: Molecular characterization, impact on treatment and liver disease progression

Hepatitis B virus (HBV) infection remains a serious public health concern worldwide despite the availability of an efficient vaccine and the major improvements in antiviral treatments. The aim of the present study is to analyze the mutational profile of the HBV whole genome in ETV non-responder chronic HBV patients, in order to investigate antiviral drug resistance, immune escape, and liver disease progression to Liver Cirrhosis (LC) or Hepatocellular Carcinoma (HCC). Blood samples were collected from five chronic hepatitis B patients. For each patient, two plasma samples were collected, before and during the treatment. Whole genome sequencing was performed using Sanger technology. Phylogenetic analysis comparing the studied sequences with reference ones was used for genotyping. The mutational profile was analyzed by comparison with the reference sequence M32138. Genotyping showed that the studied strains belong to subgenotypes D1, D7, and D8. The mutational analysis showed high genetic variability. In the RT region of the polymerase gene, 28 amino acid (aa) mutations were detected. The most significant mutations were the pattern rtL180M + rtS202G + rtM204V, which confer treatment resistance. In the S gene, 35 mutations were detected namely sP120T, sT126S, sG130R, sY134F, sS193L, sI195M, and sL216stop were previously described to lead to vaccine, immunotherapy, and/or diagnosis escape. In the C gene, 34 mutations were found. In particular, cG1764A, cC1766G/T, cT1768A, and cC1773T in the BCP; cG1896A and cG1899A in the precore region and cT12S, cE64D, cA80T, and cP130Q in the core region were associated with disease progression to LC and/or HCC. Other mutations were associated with viral replication increase including cT1753V, cG1764A/T, cC1766G/T, cT1768A, and cC1788G in the BCP as well as cG1896A and cG1899A in the precore region. In the X gene, 30 aa substitutions were detected, of which substitutions xT36D, xP46S, xA47T, xI88F, xA102V, xI127T, xK130M, xV131I, and xF132Y were previously described to lead to LC and/or HCC disease progression. In conclusion, our results show high genetic variability in the long-term treatment of chronic HBV patients causing several effects. This could contribute to guiding national efforts to optimize relevant HBV treatment management in order to achieve the global hepatitis elimination goal by 2030.

Prevalence of Hepatitis B Virus Infection Markers among Patients of the Ibn Sina University Hospital Center (Rabat, Morocco)

INTRODUCTION

Viral hepatitis B is a global scourge affecting millions of people worldwide. In Morocco, hepatitis B is considered a public health problem, and available data converge to consider Morocco as a country with intermediate endemicity. In the present study, we have planned to evaluate the HBV prevalence in Morocco on a large scale and to assess the prevalence of different serological markers for better management of this infection in Morocco.

METHODS

This study was conducted on 18,877 patients referring to the Ibn Sina University Hospital Center of Rabat, Morocco. HBV serological markers including HBsAg, HBsAb, HBeAg, HBeAb, and total HBcAb were assessed by immune-enzymatic assays. The quantification of HBV DNA was performed by real-time PCR.

RESULTS

The overall prevalence of positive cases for HBsAg, HBsAb, and total HBcAb was 2.47%, 27.66%, and 21.2%, respectively. From 141 patients with an isolated HBcAb serological profile (HBcAb+/HBsAb-/HBsAg-), HBV DNA was detected in 10 patients, representing a rate of 7.09%. In the present study, up to 95.78% of HBV chronic carriers were negative for HBeAg.

CONCLUSION

This study highlights a higher prevalence of HBsAg in the hospital-based population than the general population reported previously in Morocco and a very low HBV immunization coverage. Of particular interest, detectable HBV DNA levels in isolated HBcAb patients show that exclusive HBsAg screening cannot eliminate the risk of HBV transmission in certain cases. Many efforts are then mandatory to promote serological testing and increase the vaccination rate to limit viral dissemination for better management of this disease in Morocco.

A Systematic Review of the Current Hepatitis B Viral Infection and Hepatocellular Carcinoma Situation in Mediterranean Countries

Viral hepatitis B is a global public health problem affecting nearly two billion subjects; 3.3% of whom are from the WHO (World Health Organization) Eastern Mediterranean Region (EMRO). It induces both acute and chronic hepatic disorders with subsequent liver cirrhosis and hepatocellular carcinoma (HCC) in a considerable percentage of patients based on the age of exposure. In this review, hepatitis B virus (HBV) and HCC prevalence, distribution and prevalence of different genotypes, and male/female infection frequencies in relation to the vaccination status in the Mediterranean countries were reported. Study Design. This systematic review describes the prevalence of hepatitis B infection, genotype distribution of hepatitis B virus, and prevalence and incidence of hepatocellular carcinoma in Mediterranean countries belonging to three different continents: Southern Europe (Spain, France, Italy, Croatia, and Greece), North Africa (Morocco, Algeria, Tunisia, Libya, and Egypt), and the Near East region (Syria, Lebanon, Turkey, Israel, and Palestine). We tried to collect new data from electronic databases: PubMed, ScienceDirect, ResearchGate, Google Scholar, and public health reports between 1980 and 2019. For each publication, we recorded reference, publication year, study characteristics (date, locations, sample size, and study population), and participant characteristics (population group, year, age, and sex). No language limitation was imposed, and articles or reports from non-peer-reviewed sources were not considered for this analysis. The main keywords were HBV prevalence, hepatitis B infection, HBV genotype, and HCC. Inclusion and Exclusion Criteria. Healthy population-based studies included the following sample populations: (i) voluntary blood donors, (ii) pregnant women, (iii) community studies, (iv) hemodialysis patients, (v) hospitalized patients, (vi) healthcare workers, (vii) sex workers, (viii) drug abusers, and (ix) prisoners. We excluded studies from the following special groups who were assumed to be at a special high risk: patients from sexually transmitted disease clinics and thalassemia clinics and professional or paid blood donors.

Performance Comparison of the artus HBV QS-RGQ and the CAP/CTM HBV v2.0 Assays regarding Hepatitis B Virus DNA Quantification

Background

Over 240 million people are chronically infected with hepatitis B virus (HBV), the leading cause of liver cancer worldwide. The quantification of the HBV DNA level is critical for monitoring the efficacy of antiviral treatment of chronic HBV patients.

Methods

In our study, we compared the performance of the artus HBV QS-RGQ assay to the CAP/CTM v2.0 test, as a reference method, on 142 Moroccan patients. The analytical performance of the artus HBV QS-RGQ assay, such as the limit of detection, quantification, precision, reproducibility, and linearity, was determined using dilution series from 10 to 0.1 log₁₀ IU/mL.

Results

Detection rates and viral loads quantified by the artus HBV QS-RGQ assay were significantly lower than those from the CAP/CTM v2.0 assay (73.94% vs. 82.39%; 3.34 ± 1.94 log₁₀ IU/mL vs. 3.91 ± 2.45 log₁₀ IU/mL; p < 0.01). A Bland-Altman plot found a mean difference of (CAP/CTM v2.0 - artus HBV QS - RGQ) = 0.5717 log₁₀ IU/mL, with an average range of -1.13 to 2.31 log₁₀ IU/mL. The two methods demonstrated a high correlation (r = 0.88) for 100 positive samples, a moderate correlation for samples below 2000 IU/mL (r = 0.76), and a very high correlation for the samples above 2000 IU/mL (r = 0.95). Linearity of the artus QS-RGQ test ranged from 1.07 to 7.51 log₁₀ IU/mL.

Conclusion

The artus HBV QS-RGQ assay showed a strong correlation, precision, and linearity in comparison with the CAP/CTM v2.0. However, viral loads determined by the artus HBV QS-RGQ assay were lower than those determined by the CAP/CTM v2.0 assay.

Widespread geographical disparities in chronic hepatitis B virus infection in Algeria

Algeria is the largest country of Africa, with a population of 40 million inhabitants living in disparate environments from the Sahara to the large cities of the Mediterranean coast. The molecular epidemiology of hepatitis B virus (HBV) variants has been partially described, but variations in the seroprevalence of HBV surface antigen (HBsAg) throughout the Algerian territories are still poorly described. We analyzed demographic features of new cases of chronic infection collected in 41 administrative regions (covering 92% of the population) in 2013. The mean age of the 1876 HBsAg(+) patients was 36.8 ± 14.2 years, with a slight excess of males (54%). The seroprevalence of HBV early antigen (HBeAg) was 9.3%, and the mean virus load was 3.2 ± 1.8 log IU/ml. A subset of 15.2% of patients was already cirrhotic at disease discovery. An important heterogeneity was observed throughout the country, with nine regions displaying a significant excess of cases. These regions formed four distinct foci located in distant parts of the country: Adrar-Bechar (southwest), El-Oued-Tebessa (east), M'Sila-Sétif (north central) and Oran-Aïn Temouchent (northwest). An excess of cases was found as well in the national capital Algiers. Patients from southern regions with an excess of cases (Bechar, Adrar, El Oued) were significantly younger (32.0 ± 10.7 years), as were patients from the regions of Bejaia and Bouira (32.1 ± 10.6). The southwestern regions were also marked by a significant imbalance of the sex ratio (58 vs 39% of female cases, P = 4.5 E-5). The highest HBeAg seroprevalence was observed in Setif (26.4 vs. 7.6%, OR = 4.3, 95% CI 2.6-6.5, P = 1.1 × 10^-11) in accordance with the higher virus loads observed in the patients (3.9 ± 2.3 vs. 3.1 ± 1.6, P = 0.0002). In conclusion, we observed heterogeneity in HBsAg seroprevalence, demographic traits, and disease evolution in Algeria. Further studies are now warranted to shed light on these differences, which are presumably due to variability in transmission routes or in the infectivity of viral isolates.

A review of the infection-associated cancers in North African countries

Cancer is typically classified as a leading non-communicable disease; however, infectious agents, such as Helicobacter pylori (H. pylori), hepatitis B virus (HBV), hepatitis C virus (HCV) and human papilloma virus (HPV), contribute significantly to the pathogenesis of various cancers. Less developed countries, including countries of the North African (NA) region, endure the highest burden of infection-related cancers. The five most common infection-associated cancers in NA in order of incidence are bladder cancer, cervical cancer, liver cancer, stomach cancer, and nasopharyngeal carcinoma. This review aims to outline the epidemiologic pattern of infection-associated cancers in five NA countries (namely: Morocco, Algeria, Tunisia, Libya and Egypt) highlighting the similarities and differences across the region. The present study employed an initial literature review of peer-reviewed articles selected from PubMed, ScienceDirect and World Health Organization (WHO) databases based on key word searches without restriction on publication dates. Original research articles and reports written in French, as well as data from institutional reports and regional meeting abstracts were also included in this extensive review. Egypt, Libya, Tunisia, Algeria and Morocco were selected to be the focus of this review.

[Seroprevalence of HBsAg in pregnant women in central Morocco]

Maternal-fetal transmission of hepatitis B virus (HBV) is a global public health problem leading to the implementation of strengthened prevention measures. Viral replication in HIV-positive mother, assessed based on HBeAg positivity and the rate of viral load, determines the contamination risk which is very important during perinatal period. Mothers with chronic HBV are a real reservoir of vertical transmission of this infection. This is a prospective investigation of 1120 pregnant Moroccan women aiming to study the seroprevalence of HBsAg which was 2.35%, in order to supply the national evidence on this topic. Among these HIV-positive women who were HBsAg positive, 79.1% were HBeAg negative and underwent molecular research that was positive in 89.4% of cases. Immunization of women of childbearing age is one of the major pillars of prevention of HBV vertical transmission. Only 2.4% of our patients were vaccinated. This highlights the role of screening during pregnancy, which should focus on raising awareness about the importance of immunization in HIV-negative women and of monitoring using molecular biology tools in HIV-positive mothers in order to establish an appropriate prophylactic treatment.

Limited Genetic Diversity of Hepatitis B Virus in the General Population of the Offin River Valley in Ghana

Hepatitis B virus (HBV) infections account for approximately 780,000 deaths per year, most of which occur in the developing world. Co-infection with HBV and hepatitis delta virus (HDV) may lead to the most severe form of viral hepatitis. In Ghana, knowledge on the prevalence of HBV and HDV in the general population is scanty and the few genetic analyses of the prevailing HBV genotypes are dating back more than a decade. In the present study, 1,323 serum samples from individuals living in a rural area (Offin river valley) of Ghana were analyzed for the presence of the hepatitis B surface antigen (HBsAg). Positive sera were subsequently tested for the presence of anti-HDV antibodies. A total of 107 (8%) sera were HBsAg positive with an 8.4% prevalence of anti-HDV antibodies among the HBsAg positives. Phylogenetic analysis based on HBV pre-S/S sequences, attributed all 52 typable samples to genotype E. All belonged to serotype ayw4. While 19 sequences clustered with those from a number of African countries, the other 33 formed a separate cluster distinguished by an intergroup mean distance of 1.5% from the pan-African HBV/E cluster. Successful implementation of HBV vaccination in the region was reflected by the low HBsAg carrier rate of 1.8% among children ≤11 years.

Prevalence of mutations within major hydrophilic region of hepatitis B virus and their correlation with genotypes among chronically infected patients in Egypt

BACKGROUND AND STUDY AIMS

Mutations within the major hydrophilic region (MHR) of the hepatitis B surface antigen (HBsAg) have been reported in relation to viral persistence by evasion from vaccine and immunotherapy, severity of liver disease and lack of detection by commercial kits. The aim of this study was to elucidate the circulation of hepatitis B virus (HBV) genotypes, subgenotypes and serotypes in Egypt, with recognition of the pattern and prevalence of MHR mutations possibly occurring during the course of the disease.

PATIENTS AND METHODS

Eighty-eight samples from patients with chronic HBV infection were included in the study. The surface protein-encoding gene (S gene) in the HBV genome was subjected to amplification and partial sequencing.

RESULTS

Based on phylogenetic analysis, only genotype D was found circulating among patients. The majority of isolates belonged to subgenotype D3 (86.3%), followed by D7 (8%), then D5 (3.4%) and lastly D1 (2.3%). Two subtypes were identified: ayw2 (97%) and ayw3 (2%). The 'w' sub-determinant was not defined in one isolate (1%). A significant proportion of patients (13/88, 14.8%) exhibited mutations in the MHR, 10 of whom harboured mutations in the 'a' determinant region and three outside. The first loop comprised four patients with three mutations (P127S, P127T and Y134F). The second loop contained six patients, all with one mutation, S143L, which was most frequently encountered in this study (6.8%).

CONCLUSIONS

We conclude that genotype D, subgenotype D3 and HBsAg subtype ayw2 are the most common types circulating in Egypt, which account for 100%, 86.3% and 97% of the population, respectively, with a moderate degree of MHR mutations.

Molecular epidemiology of hepatitis B and Delta virus strains that spread in the Mediterranean North East Coast of Tunisia

BACKGROUND

Tunisia is classified as an area of middle endemic for hepatitis B virus (HBV) infection, however little is known about hepatitis Delta virus (HDV) infection.

OBJECTIVES

This study aimed to address the prevalence of HDV infection, to identify possible risks factors, and to analyze the genetic diversity of HDV strains that are spreading in Tunisia.

STUDY DESIGN

A retrospective large-scale study including 1615 HBsAg positive patients, native of the North East coast of Tunisia, recruited from Gastroenterology departments, was conducted. Demographic, epidemiological, ethnical, clinical and biological data were recorded. HBV and HDV serological analyses and DNA and RNA viral load quantification were performed. Genotyping of HBV and HDV strains was performed using nucleotide sequencing followed by phylogenetic analyses.

RESULTS

The study population included 819 (50.7%) men and 796 (49.3%) women; aged 12-90 years (mean age 41±13 years). A very low prevalence of HDV infection, 2% was observed. No risk factor, except a history of hospitalization for surgery was found. All HDV strains belonged to genotype 1, with a wide distribution within the HDV-1 group. They all share the African amino acid marker, a serine at position 202 of the large Delta protein. HBV genotypes were distributed as follows: HBV/D1 (56.8%), HBV/D7 (40.9%), and HBV/A2 (2.3%).

CONCLUSION

Tunisia is a low endemic region for HDV infection, due to an efficient policy of HBV infection control. HDV-1 is the sole genotype found, with a high diversity within this group. Further studies are ongoing in order to better characterize and manage the HBV/HDV-infected patients according to the genetic variability of the viral strains.

Evaluation of PCR-RFLP in the Pre-S Region as Molecular Method for Hepatitis B Virus Genotyping

BACKGROUND

Hepatitis B virus (HBV) infection is a public health problem in developing countries. HBV genotypes play major role in the evolution of infection since they were involved in different clinical presentations and response to treatment.

OBJECTIVES

This study was conducted to evaluate the efficiency of restriction fragment length polymorphism (RFLP) analysis for HBV genotyping.

PATIENTS AND METHODS

We investigated 98 samples collected from patients chronically infected with HBV. HBV genotypes were determined by analysis of patterns obtained after amplification in Pre-S region and digestion of the amplicon by two endonucleases AvaII and DpnII. Obtained results were confirmed by partial sequencing in the same region.

RESULTS

Two different HBV genotypes were detected in this study, Genotype D (in 95. 9%) and Genotype A (in 4.1%). Seventy-four samples (75.5%) were successfully genotyped with RFLP analysis and all classified as genotype D. The remaining 24 samples (24.5%) which were un-genotyped by RFLP analysis, were classified by partial sequencing of the pre-S region as HBV genotype D (20 samples, 20.4%) and genotype A (4 samples, 4.1%). Atypical profiles were significantly associated with advanced liver disease (P = 0.001) as well as older age (P < 0.05).

CONCLUSIONS

Several previous studies used PCR-RFLP to genotype HBV; however, we showed the high risk to obtain atypical profiles, especially in advanced stages of chronic infection, with as results difficulties to genotype the virus. These profiles resulted from the accumulation of mutations during natural course of infection resulting in a modification in restriction sites for enzymes. So, we recommended completing the investigation by partial sequencing to confirm obtained results.

Polymorphic APOBEC3 modulates chronic hepatitis B in Moroccan population

The cytidine deaminase apolipoprotein B mRNA editing catalytic subunit-3 (APOBEC3) induces G-to-A hypermutation in hepatitis B virus (HBV) genomes and operates as part of the innate antiviral immune system. We investigated the associations between the presence of APOBEC3 variants and HBV carriage in a case-control study in the Moroccan population. A polymorphic deletion affecting the APOBEC3B gene and the H186R variant of APOBEC3G were genotyped in 179 HBV chronic carriers and 216 healthy control subjects. In addition, to assess the overall impact of APOBEC3 deaminases on circulating HBV, we looked for hyperedited forms of the viral genome using the 3DPCR technique and analysed editing context. Data analysis showed that there was no significant difference in the frequencies of deleted APOBEC3B alleles (P = 0.261) or genotypes (P = 0.333) between patients with chronic hepatitis B and control subjects. By contrast, subjects bearing deleted genotype had a faster progression of liver disease than those with the insertion genotype (adjusted OR, 3.72; 95% CI, 0.38-36.12). The analysis of the APOBEC3G H186R polymorphism revealed that R/R genotype frequencies were not significantly different in HBV infected patients and in healthy subjects. 3DPCR was positive in 26 samples (14%) among 179. Amplified viral segments displayed monomorphic G>A transitions highly reminiscent of APOBEC3G activity. Most intriguingly, hemi/homozygous carriers of the APOBEC3B deletion had significantly lower virus loads than patients with the wild type (median 539 vs. 2213 IU/mL, P = 0.0023). This result suggests that genetic variations in APOBEC3 cytidine deaminases do not predispose to chronicity but may modulate the course of persistent HBV infection.

Hepatitis B virus in the Maghreb region: from epidemiology to prospective research

Hepatitis B virus (HBV) represents an important health problem in the Maghreb countries, Algeria, Libya, Mauritania, Morocco and Tunisia, but no detailed synthesis of its epidemiology is available. In this review, we systematically searched for data about HBV in the Maghreb in peer-reviewed databases and included in our analysis works written in English and French, as well as institutional reports and regional conference meeting abstracts. We estimated national and regional prevalence of chronic HBV infection. In addition, we discuss molecular features of the viral strains circulating in the region. Data analysis suggests that in the Maghreb region HBs antigen carriage concerns 1.8-4.9% of the population for an estimated number of 2.7 million persons. Genotype D, subtype D7, is predominant and mutations in the precore region of HBV genome are highly prevalent. This epidemiological situation requires obviously widespread active interventions for prevention and control. In addition, anti-hepatitis B vaccination programme should be applied with the utmost discipline in the five countries considered in this present review. This systematic review will, hopefully, increase knowledge at disposal of Public Health authorities, enabling better resource allocation and healthcare delivery. The present synthesis intends to stimulate policies aiming at preventing the spread of HBV, keeping in mind that eradication of the virus from Maghrebi populations should be the ultimate objective of Public Health authorities.

Variability in the precore and core promoter regions of HBV strains in Morocco: characterization and impact on liver disease progression

Background

Hepatitis B virus (HBV) is one of the most common human pathogens that cause aggressive hepatitis and advanced liver disease (AdLD), including liver cirrhosis and Hepatocellular Carcinoma. The persistence of active HBV replication and liver damage after the loss of hepatitis B e antigen (HBeAg) has been frequently associated with mutations in the pre-core (pre-C) and core promoter (CP) regions of HBV genome that abolish or reduce HBeAg expression. The purpose of this study was to assess the prevalence of pre-C and CP mutations and their impact on the subsequent course of liver disease in Morocco.

Methods/Principal Findings

A cohort of 186 patients with HBeAg-negative chronic HBV infection was studied (81 inactive carriers, 69 with active chronic hepatitis, 36 with AdLD). Pre-C and CP mutations were analyzed by PCR-direct sequencing method. The pre-C stop codon G1896A mutation was the most frequent (83.9%) and was associated with a lower risk of AdLD development (OR, 0.4; 95% CI, 0.15–1.04; p = 0.04). HBV-DNA levels in patients with G1896A were not significantly different from the other patients carrying wild-type strains (p = 0.84). CP mutations C1653T, T1753V, A1762T/G1764A, and C1766T/T1768A were associated with higher HBV-DNA level and increased liver disease severity. Multiple logistic regression analysis showed that older age (≥40 years), male sex, high viral load (>4.3 log₁₀ IU/mL) and CP mutations C1653T, T1753V, A1762T/G1764A, and C1766T/T1768A were independent risk factors for AdLD development. Combination of these mutations was significantly associated with AdLD (OR, 7.52; 95% CI, 4.8–8; p<0.0001).

Conclusions

This study shows for the first time the association of HBV viral load and CP mutations with the severity of liver disease in Moroccan HBV chronic carriers. The examination of CP mutations alone or in combination could be helpful for prediction of the clinical outcome.

Reconstruction of the epidemic history of hepatitis B virus genotype D in Albania

Despite a recent decrease in the prevalence of HBsAg in the general population, Albania is still highly endemic for HBV infection. Genotype D is the most prevalent HBV strain in the Mediterranean area. We studied the prevalence and distribution of HBV genotypes and subgenotypes in a total of 73 HBsAg-positive patients living in Albania, and reconstructed the epidemiological history of the most prevalent HBV D subgenotype using a "phylodynamic" framework. A time-scaled genealogy of the Albanian patients' and reference P gene sequences with known sampling dates was reconstructed using an MCMC Bayesian approach that allows population growth to be estimated on the basis of coalescent theory. All of the Albanian subjects were infected with the HBV D genotype, and a percentage varying from 44.4% to 100% (depending on the ethnic or risk group) were infected with subgenotype D2, the most prevalent in the study population (72.4%). The other subgenotypes present in a minority of subjects were D1 (13.8%) and D3 (13.8%). The Bayesian skyline plot population dynamics analysis showed that genotype D2 entered the Albanian population in the late 1960s, and that the effective number of infections grew gradually until the second half of the 1980s and more rapidly until the mid-1990s, when it reached a plateau that still persists today. Our data suggest that political and socio-economic factors played an important role in determining the rapid spread of HBV infection in Albania.

Hepatitis B genotypes/subgenotypes and MHR variants among Moroccan chronic carriers

OBJECTIVES

The aim of this study was to determine the prevalence of Hepatitis B Virus (HBV) genotypes, subgenotypes, HBV surface antigen (HBsAg) subtypes and naturally occurring mutations in Major Hydrophilic region (MHR) of HBsAg among Moroccan patients with chronic HBV infection.

METHODS

The study included 200 patients chronically infected with HBV. The HBV genotypes, subgenotypes, HBsAg subtypes and MHR variants were determined by direct sequencing of the HBV surface (S) gene and phylogenetic analysis.

RESULTS

The S gene was successfully amplified in 134 patients. The mean age was 40.6 ± 12.2 years. Genotype D was predominant (90%, 120/134) and genotype A was less frequent (10%, 14/134). Genotype D strains belonged to subgenotypes D7 (70.8%, 85/120), D1 (25.8%, 31/120) and D2 (0.9%, 1/120). Three strains (2.5%) could not be classified in any subgenotype of genotype D. All genotype A strains belonged to subgenotype A2. HBsAg subtypes found were ayw2 (82.1%, 110/134), adw2 (10.4%, 14/134), ayw3 (3%, 4/134) and ayw4 (3%, 4/134). The global prevalence of MHR variants was 15% (20/134) with substitution P120T/S the most frequent (3.7%, 5/134). The occurrence of MHR variants was significantly associated with advancing age (>40 years) (p = 0.003) and independent of sex, HBeAg status, viral load, genotype, subgenotype and HBsAg subtype.

CONCLUSIONS

This study provides the first description of predominance of HBV subgenotype D7/subtype ayw2 among Moroccan HBV chronic carriers. It also showed a significant prevalence of naturally occurring MHR variants in Morocco.

First multicenter study for risk factors for hepatocellular carcinoma development in North Africa

AIM

To assess the role of the major risk factors for hepatocellular carcinoma (HCC) development in the western part of North Africa.

METHODS

A multicenter case control study was conducted in Tunisia, Morocco and Algeria in collaboration with Pasteur Institutes in these countries. A total of 164 patients with HCC and 250 control subjects without hepatic diseases were included. Prevalences of HBsAg, anti-hepatitis C virus (HCV) and diabetes were assessed. HCV and HBV genotyping were performed for anti-HCV and HBsAg positive patients.

RESULTS

The mean age of patients was 62 ± 10 years old for a 1.5 M:F sex ratio. Sixty percent of HCC patients were positive for anti-HCV and 17.9% for HBsAg. Diabetes was detected in 18% of cases. Odd ratio (OR) and 95% confidence intervals (CI) were 32.0 (15.8 - 65.0), 7.2 (3.2 - 16.1) and 8.0 (3.1 - 20.0) for anti-HCV, HBsAg and diabetes respectively. Multivariate analysis indicated that the three studied factors were independent. 1b HCV genotype and D HBV genotype were predominant in HCC patients. HCV was the only risk factor significantly associated with an excess of cirrhosis (90% vs 68% for all other risk factors collectively, P = 0.00168). Excessive alcohol consumption was reliably established for 19 (17.6%) cases among the 108 HCC patients for whom data is available.

CONCLUSION

HCV and HBV infections and diabetes are the main determinants of HCC development in North Africa. An active surveillance and secondary prevention programs for patients with chronic hepatitis and nutrition-associated metabolic liver diseases are the most important steps to reduce the risk of HCC in the region.

Molecular analysis of HBV genotypes and subgenotypes in the Central-East region of Tunisia

Background

In Tunisia, country of intermediate endemicity for Hepatitis B virus (HBV) infection, most molecular studies on the virus have been carried out in the North of the country and little is known about other regions. The aim of this study was to determine HBV genotype and subgenotypes in Central-East Tunisia. A total of 217 HBs antigen positive patients were enrolled and determination of genotype was investigated in 130 patients with detectable HBV DNA. HBV genotyping methods were: PCR-RFLP on the pre-S region, a PCR using type-specific primers in the S region (TSP-PCR) and partial sequencing in the pre-S region.

Results

Three genotypes (D, B and A) were detected by the PCR-RFLP method and two (D and A) with the TSP-PCR method, the concordance between the two methods was 93%. Sequencing and phylogenetic analysis of 32 strains, retrieved the same genotype (D and A) for samples with concordant results and genotype D for samples with discordant results. The sequences of discordant genotypes had a restriction site in the pre-S gene which led to erroneous result by the PCR-RFLP method. Thus, prevalence of genotype D and A was 96% and 4%, respectively. Phylogenetic analysis showed the predominance of two subgenotypes D1 (55%) and D7 (41%). Only one strain clustered with D3 subgenotype (3%).

Conclusions

Predominance of subgenotype D7 appears to occur in northern regions of Africa with transition to subgenotype D1 in the East of the continent. HBV genetic variability may lead to wrong results in rapid genotyping methods and sequence analysis is needed to clarify atypical results.

A novel hepatitis B virus (HBV) subgenotype D (D8) strain, resulting from recombination between genotypes D and E, is circulating in Niger along with HBV/E strains

Niger is a west African country that is highly endemic for hepatitis B virus (HBV) infection. The seroprevalence for HBV surface antigen (HBsAg) is about 20%; however, there are no reports on the molecular epidemiology of HBV strains spreading in Niger. In the present study, HBV isolates from the sera of 58 consecutive, asymptomatic, HBsAg-positive blood donors were characterized. Genotype affiliation was determined by amplification, sequencing and phylogenetic analysis of the preS1, polymerase/reverse transcriptase (RT/Pol) and precore (preC)/C regions. The first series of results revealed that different genomic fragments clustered with different genotypes on phylogenetic trees, suggesting recombination events. Twenty-four complete genomic sequences were obtained by amplification and sequencing of seven overlapping regions covering the whole genome, and were studied by extensive phylogenetic analysis. Among them, 20 (83.3%) were classified unequivocally as genotype E (HBV/E). The remaining four (16.7%) clustered on a distinct branch within HBV/D with strong bootstrap and posterior probability values. Complete molecular characterization of these four strains was achieved by the Simplot program, bootscanning analysis and cloning experiments, and enabled us to identify an HBV/D-E recombinant that formed a new HBV/D subgenotype spreading in Niger, tentatively named D8. Moreover, 20 new complete HBV/E nucleotide sequences were determined that exhibited higher genetic variability than is generally described in Africa. One was found to be a recombinant containing HBV/D sequences in the preS2 and RT/Pol regions. Taken together, these data suggest that, in Niger, genetic variability of HBV strains is still evolving, probably reflecting ancient endemic HBV infection.

Viral hepatitis a to e in South mediterranean countries

Viral hepatitis represents an important health problem in the South Mediterranean countries, Egypt, Libya, Tunisia, Algeria and Morocco. Emerging natural history and epidemiological information reveal differences in the overall epidemiology, risk factors and modes of transmission of viral hepatitis A, B, C, D, E infections in the South Mediterranean region. The differences in the in incidence and prevalence of viral hepatitis across North African countries is attributed to variations in health care and sanitation standards, risk factors and immunization strategies. The active continuous population movement through travel, tourism and migration from and to the South Mediterranean countries contribute to the spread of infections due to hepatitis viruses across borders leading to outbreaks and emergence of new patterns of infection or introduction of uncommon genotypes in other countries, particularly in Europe.

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.

[Characteristics of hepatitis B viral strains in chronic carrier patients from North-East Algeria]

OBJECTIVE

The goal of the study was to determine the characteristics of chronic hepatitis B virus (HBV) infections in the north-east part of Algeria. Chronic HBV infection remains a global public health issue and Algeria is considered as an intermediate prevalence area. Improving our knowledge on the epidemiology of this infection is a prerequisite to adopt the best preventive and curative strategy.

MATERIAL AND METHODS

We have studied 75 chronic hepatitis B patients from north-east Algeria. The characteristics of HBV strains were determined by use of serological and molecular testing. Genes encoding part of the precore, the surface and the polymerase were sequenced and phylogenetically analyzed.

RESULTS

Median age of the patients was 35 years and 80% of them had normal transaminase level. Liver histological lesions were identified in 63% of the patients who benefited from a liver biopsy and 21% of them had cirrhosis. Median viral replication was 3.9 Log IU/ml and 87% of patients had a "precore" mutant serological profile without HBe Ag. Genotype D was predominant (93%) followed by genotype A (5%) and E for one patient. Algerian strains clustered independently from other genotype D reference sequences, suggesting a possible new D subtype. Within the "precore" region, only 16% of the strains did not show any mutation at positions 1762/1764 and 1896.

CONCLUSION

In this original set of patients from north Algeria, the virologic characteristics of HBV are comparable to what has been described in other Mediterranean countries. Our study raises several important aspects with regard to the prevention and treatment of chronic hepatitis B in Algeria.