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Introduction: Hepatotropic viruses (HAV, HBV, HCV, HDV, and HEV) significantly impact global health, with varying prevalence across regions., Objective: This study aims to systematically consolidate data from diverse meta-analyses to provide a contemporary reference on virus distribution and prevalence., Materials and Methods: Adhering to PRISMA guidelines, the study utilized a mixed effects model for data integration. Quality evaluation was carried out with QUOROM and AMSTAR tools, with heterogeneity assessed via the Higgins I2 statistic, Q-statistic and Tau squared (τ 2 ) values., Results: The study analyzed 86 meta-analyses from 56 studies (2017-2022) with minimal overlap. Prevalence rates by region were as follows: MENA - 29.2%, Afghanistan - 9.14%, Africa - 8.10%. Prevalence rates by virus type: HAV - 82.5%, HBV - 8.6%, HCV - 15.1%, HDV - 8.9%, HEV - 13.9%, dual HBV-HCV coinfection - 2.2%. Prevalence rates by risk groups: general population - 8.3%, healthcare workers - 4.0%. Continent-specific HBV-HCV prevalence rates: Africa - 9.2%, China - 6.9%, others. HCVprevalence rates among at-risk groups: healthcare workers - 5.58%, hemodialysis patients - 34.8%. Regional HCV rates: Africa - 7.42%, Middle East - 25.30%., Conclusion: Diverse global hepatotropic virus prevalence patterns are influenced by multifaceted factors. MENA faces higher rates due to healthcare challenges, while Africa struggles with limited resources. Tailored public health strategies, including vaccination and awareness campaigns, are essential to alleviate burdens and enhance global health. This consolidated data serves as a valuable resource for informed decision-making.

Hepatitis B virus (HBV) Infection remains a public health problem and a threat to blood transfusion safety. The aim of this study was to summarise the scientific literature on the seroprevalence of HBV and occult HBV among blood donors in Africa. Searches were carried out in PubMed, Science Direct, Global Index Medicus and African Journals Online from 2012 to 2022. Dersimonian and Laird's random-effects model-based method was used for statistical analyses to estimate pooled seroprevalence at a 95% confidence interval (CI) using STATA version 14 software. Heterogeneity was assessed on the basis of Cochran's Q test and quantified by the I 2 index. The methodological quality of the articles was assessed using the Joanna Brigg Institute's critical appraisal checklist. Among 90 articles included, 86 reported data in serological test that a pooled HBV seroprevalence of 5.53% (95% CI: 4.56-6.58; I 2  = 99.94%) and 14 provided occult hepatitis B data. A high prevalence of 9.69% (95% CI: 8.42-11.03) was observed in the West African region. Lowest prevalence was 1.22% (95% CI: 0.74-1.83) in South Africa region. Prevalence in Africa among men was: 5.18% (95% CI: 3.97-6.54) and in women: 3.50% (95% CI: 2.45-4.71) (I 2  = 99.76% and p < 0.01). While the overall pooled prevalence of occult hepatitis B was 3.18% (95% CI: 1.29-5.81). HBV seroprevalence is high in low-resource areas of Africa, and the data generated by this situation calls for constant epidemiological surveillance. Emphasis must be placed on building blood donor loyalty and integrating molecular testing into the biological qualification of blood donations., (© 2024 John Wiley & Sons Ltd.)

This study aims to characterize the molecular profile of the hepatitis B virus (HBV) among socially vulnerable immigrants residing in Brazil to investigate the introduction of uncommon HBV strains into the country. Serum samples from 102 immigrants with positive serology for the HBV core antibody (anti-HBc) were tested for the presence of HBV DNA by PCR assays. Among these, 24 were also positive for the HBV surface antigen (HBsAg). The full or partial genome was sequenced to determine genotype by phylogenetic analysis. Participants were from Haiti (79.4%), Guinea-Bissau (11.8%), Venezuela (7.8%), and Colombia (1%). Of the 21 HBV DNA-positive samples, subgenotypes A1 (52.4%), A5 (28.6%), E (9.5%), F2 (4.8%), and F3 (4.8%) were identified. Among the 78 HBsAg-negative participants, four were positive for HBV DNA, resulting in an occult HBV infection rate of 5.1%. Phylogenetic analysis suggested that most strains were likely introduced to Brazil by migration. Importantly, 80% of A5 sequences had the A1762T/G1764A double mutation, linked to an increased risk of hepatocellular carcinoma development. In conclusion, this study is the first report of HBV subgenotype A5 in Brazil, shedding new light on the diversity of HBV strains circulating in the country. Understanding the genetic diversity of HBV in immigrant communities can lead to better prevention and control strategies, benefiting both immigrants and wider society.

Objectives: Widespread testing and treatment are essential to eliminate hepatitis B virus (HBV) infection as a public health concern. However, in resource-limited countries, access to HBV PCR is limited. In this study, we developed a quantitative HBV PCR assay on open molecular platforms and evaluate its performance in diagnosing clinically significant HBV DNA thresholds as defined by the WHO (2000 IU/mL, 20 000 IU/mL, and 200 000 IU/mL)., Methods: We implemented our HBV PCR test in seven African and Asian countries and France, using either an in-house laboratory method or a European conformity for in vitro diagnostic (CE-IVD) marked version of the PCR (Generic HBV Charge Virale, Biocentric). Results were compared with reference tests (Roche Cobas AmpliPrep/Cobas TaqMan and Abbott RealTime on Abbott m2000)., Results: There was a good agreement between the HBV DNA results of 1015 samples tested by the PCR on open polyvalent platforms and the results from reference tests (mean difference (bias ± standard deviation [SD]): -0.3 ± 0.7 log 10 IU/mL and -0.2 ± 0.9 log 10 IU/mL when compared with Roche and Abbott tests, respectively). Kappa-Cohen agreements between the HBV PCR on open polyvalent platforms and the Roche/Abbott assays appeared almost perfect for HBV DNA levels ranged from >20 000 to 200 000 IU/mL and >200 000 IU/mL, substantial and moderate for HBV DNA levels ranged from 2000 to 20 000 IU/mL when compared with Abbott and Roche, respectively. The assay's performance was consistent across genotypes A, B, C, D, and E., Discussion: This field evaluation showed that our HBV PCR test is a valuable alternative to proprietary PCR systems. PCR assays on open platforms contribute to expanding clinical laboratory solutions for diagnosing individuals who meet the viral load criteria for antiviral therapy (>20 000 IU/mL) and mother-to-child prophylaxis (>200 000 IU/mL)., (Copyright © 2024. Published by Elsevier Ltd.)

In 2016 the World Health Organization set the goal of eliminating hepatitis B globally by 2030. Horizontal transmission has been greatly reduced in most countries by scaling up coverage of the infant HBV vaccine series, and vertical transmission is therefore becoming increasingly dominant. Here we show that scaling up timely hepatitis B birth dose vaccination to 90% of new-borns in 110 low- and middle-income countries by 2030 could prevent 710,000 (580,000 to 890,000) deaths in the 2020 to 2030 birth cohorts compared to status quo, with the greatest benefits in Africa. Maintaining this could lead to elimination by 2030 in the Americas, but not before 2059 in Africa. Drops in coverage due to disruptions in 2020 may lead to 15,000 additional deaths, mostly in South-East Asia and the Western Pacific. Delays in planned scale-up could lead to an additional 580,000 deaths globally in the 2020 to 2030 birth cohorts., (© 2021. The Author(s).)

Background: Due to its invasive procedure patients on hemodialysis (HD) are at high risk of infections. Infections acquired in dialysis units can prolong hospitalization date and/or prolong illness in patients, and increase treatment cost. There are no adequate data on the prevalence of Hepatitis B virus (HBV) and Hepatitis C virus (HCV) infections in HD patients. Therefore, this study aimed to estimate the pooled prevalence and associated factors of HBV and HCV infections among HD patients in Africa., Method: The databases PubMed, Medline, EMBASE, Cochrane library, web of science, African Journals Online, Science Direct, and Google Scholar were searched to identify relevant studies. The review was performed based on Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Data were extracted independently by two authors and analyzed using STATA 11. A random-effect model was fitted to estimate the pooled prevalence with their 95% confidence interval. To detect publication bias funnel plots analysis and Egger weighted regression tests were done., Results: The overall pooled prevalence of HBV and HCV infection among HD patients in Africa was 9.88% (95% CI: 7.20-12.56) I2 = 97.9% and 23.04% (95% CI: 18.51-2757) I2 = 99.6%, respectively. In addition, the pooled prevalence of HBV and HCV co-infection was 7.18% (95% CI: 3.15-11.20) I2 = 99.6%. Duration of dialysis was found to be the contributing factor for the occurrence of HBV and HCV among HD patients (OR = 1.44; 95% CI: 1.04, 2.01)., Conclusion: This study showed that there is high prevalence of HBV and HCV infections in HD patients in Africa. Therefore, strict adherence to precautions of infection control measures, isolation of seropositive patients, improvement in infrastructures, adequate screening of HBV and HCV for the donated blood, and decentralized HD services is needed to minimize the risk of HBV and HCV infections in HD facilities., Competing Interests: The authors have declared that no competing interests exist.

Background: Hepatitis B virus (HBV) infection is a significant occupational hazard in health care settings and represents a public health concern. The aim of this study was to investigate the association between medical waste handling and HBV infection by conducting a meta-analysis of available evidence., Methods: Pooled odds ratios (ORs) and confidence intervals (CIs) of the included studies were calculated, using the random-effects model, for medical waste handlers versus non-medical waste handlers. Publication bias was detected using the regression test for funnel plot asymmetry, and quality assessment was conducted according to the Newcastle-Ottawa Scale., Results: Nine cross-sectional studies, published between 1992 and 2018, were included. Medical waste handling was associated with higher odds of HBV infection compared to non-medical waste handling (pooled OR = 2.88; 95% CI, 1.40-5.93; I 2  = 61.36%; P value for heterogeneity = .008). Subgroup analysis showed higher odds of HBV infection in studies conducted in Africa (pooled OR = 3.61; 95% CI, 1.19-11.00). Most studies were of poor to fair quality; yet, little evidence of publication bias was detected (P value for publication bias = .983). No single study showed a substantial impact on the pooled results., Conclusions: The present meta-analysis supports the suggestion that medical waste handling is associated with HBV infection. This association was shown to be more obvious in African health care settings., (Copyright © 2019 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.)

Hepatitis B virus infection in Africa is characterised by distinct genotypes with observed differences in natural history and clinical outcomes. Replication-competent cDNA clones of African genotypes were generated from patient-derived sequences identified in African children with chronic hepatitis B infection living in Australia: A1 (wild-type and basal core promotor (BCP) mutant), D2, D6, and E, comparing the replication phenotype to an established D3 cDNA clone in a transient transfection cell culture model. All clones replicated efficiently although less than the European D3 reference clone, and demonstrated marked differences in replication capacity, highest for subgenotypes A1 and D2. The BCP mutation increased the replication levels of the A1 subgenotype compared to wild-type. Intracellular and secreted surface antigen and HBeAg protein expression also varied across genotypes. We observed differences in functional activity in the upstream regulatory region across the genotypes that may contribute to the replication and protein differences observed., (Copyright © 2019. Published by Elsevier Inc.)

Migration from sub-Saharan Africa is contributing to the rising incidence of chronic hepatitis B (CHB) infection and its complications in Australia. African CHB is associated with unique genotypes, such as E and A1, which are associated with reduced vaccine efficacy and early-onset hepatocellular carcinoma, respectively, although the prevalence of these genotypes outside Africa is poorly described. Treatment-naïve children of African origin with CHB were recruited at the Royal Children's Hospital Melbourne. Population-based sequencing of the complete HBV genome, or the clinically relevant basal core promoter (BCP)/precore (PC) region, was performed, and the HBV genotype/subgenotype assigned by phylogenetic analysis. HBV was characterized in serum from 67 children, median age 12.5 years. HBV genotype E was most frequent (70 %), with genotype D [25 %; subgenotypes D6 (formerly D7)/D3/D2)] and subgenotype A1 (5 %) also being identified. Despite their young age, over 50 % of the children were HBeAg-negative and had seroconverted to anti-HBe, with this being associated with canonical BCP/PC mutations in the majority of cases. The profile of HBV in African children living in Australia was characterized by early HBeAg seroconversion and infection with HBV variants associated with poor clinical outcome, as well as genotypes previously associated with reduced vaccine efficacy or rapid progression to liver cancer. These findings have important ramifications for patient monitoring and treatment guidelines in the Australian paediatric setting.

The worldwide distributed Hepatitis B virus (HBV) genotype A is classified into three subgenotypes, and one quasi-subgenotype. The majority of HBV-A subgenotypes are widespread in Africa and in ethnic groups that have relatively recently emigrated from African countries, whereas HBV-A2 is highly prevalent among subjects at high risk for sexual exposure to HBV in north-western Europe and the USA. The aim of this study was to reconstruct the origin and dispersion of HBV-A subgenotypes on a reliable timescale using short-term calibration based on heterochronous sampling for HBV-A2, and long-term calibration based on historical data for the other subgenotypes. To this aim, we analysed 113 newly characterised HBV-A isolates with 247 reference sequences retrieved from a public database. The phylodynamic reconstruction was performed by a Bayesian framework. The common ancestor of the currently circulating A subgenotypes was placed in west-central Africa a mean 1057 years ago. The genotype diverged into two main clades at the beginning of the 13th century: one including all of the west-central African quasi-subgenotypes and the other corresponding to subgenotype A1, originating in east Africa and further segregating into two main subclades: an "African" and a "cosmopolitan" clade. It is likely that the slave trade was the main source the spread of cosmopolitan HBV-A1, which was exported to Asia in the 17th century as a result of Arab or Portuguese trade, and to Latin America in the 18th centuries through the trans-Atlantic slave trade. The origin of the currently circulating A2 strains dates back to the first decades of the 20th century, and the evolutionary demography analysis suggests an exponential growth of infections, between 1970s and the mid-1990s. In conclusion, the very different epidemiological and evolutionary histories of HBV-A subgenotypes justify the use of different calibration approaches to reconstruct their reciprocal phylodynamics., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Brazil is a country of low hepatitis B virus (HBV) endemicity in which the genotype A of HBV (HBV/A) is the most prevalent. The complete nucleotide sequences of 26 HBV/A isolates, originating from eight Brazilian states, were determined. All were adw2. Twenty-three belonged to subgenotype A1 and three to A2. By phylogenetic analysis, it was shown that all the 23 HBV/A1 isolates clustered together with isolates from Bangladesh, India, Japan, Nepal, the Philippines and United Arab Emirates, but not with those of Congo, Kenya, Malawi, Rwanda, South Africa, Tanzania, Uganda and Zimbabwe. Four amino acid residues in the polymerase (His138 in the terminal protein domain, Pro18 and His90 in the spacer, and Ser109 in the reverse transcriptase), and one (Phe17) in the precore region, predominated in Latin American and Asian HBV/A1 isolates, but were rarely encountered in African isolates, with the exception of those from Somalia. Specific variations of two adjacent amino acids in the C-terminal domain of the HBx protein, namely Ala146 and Pro147, were found in all the Brazilian, but rarely in the other HBV/A1 isolates. By Bayesian analysis, the existence of an 'Asian-American' clade within subgenotype A1 was supported by a posterior probability value of 0.996. The close relatedness of the Brazilian, Asian and Somalian isolates suggests that the HBV/A1 strains predominant in Brazil did not originate from the five million slaves who were imported from Central and Western Africa from 1551 to 1840, but rather from the 300-400,000 captives forcibly removed from southeast Africa at the middle of the 19th century.

The aim of this study was to determine the prevalence of active hepatitis B and C virus infections among refugees from various countries in Africa and Asia. Pre-admission serum samples collected during 2002-2007 from refugees originating from Bhutan (N = 755), Myanmar (N = 1076), Iraq (N = 1137), Laos (N = 593), Thailand (N = 622), and Somalia (N = 707) were tested for hepatitis B virus (HBV) DNA and hepatitis C virus (HCV) RNA. The HBV DNA (genotypes A, B, C, and G) was detected in 12.1% of samples negative for anti-HBs. Highest HBV prevalence was found among Hmong; lowest among Bhutanese. The HCV RNA (genotypes 1a, 1b, 1c, 3b, 6n, and 6m) was detected in 1.3% of the samples. Highest HCV prevalence was found among Hmong from Thailand; lowest among Iraqis. Screening specific refugee groups at high risk for viral hepatitis infections will identify infected individuals who could benefit from referral to care and treatment and prevent further transmissions., (© The American Society of Tropical Medicine and Hygiene.)

Ten Hepatitis B virus (HBV) genotypes, as well as numerous subgenotypes, have been described in well-characterized ethnogeographical populations. Martinique has been at a crossroads between Africa, Europe, India and the Americas because of the slave trade (17th-19th centuries), followed by an important immigration of Indian and West African workers. In this work, we aimed to study the molecular epidemiology of HBV infection in Martinique according to this unique settlement pattern. To that end, blood samples from 86 consecutive HBV-infected patients from the main hospitals of the island, were retrospectively analysed. Direct sequencing of the pre-S1 or pre-C-C region or complete genome sequencing, followed by phylogenetic analyses were performed. HBV genotypes were: HBV/A1 (68.6 %), HBV/A2 (10.5 %), HBV/D, mainly HBV/D3 and HBV/D4 (8.1 %), HBV/F (3.5 %), and also HBV/E (2.3 %), two strains isolated from two West-African patients. Moreover, 74 % of the HBeAg-negative strains harboured classical pre-C-C mutations, and most HBV/A1 strains also containing specific mutations. Finally, various patterns of deletion mutants in pre-S and pre-C-C regions were found. In conclusion, our findings point to historical and migration-related issues in HBV-genotype distribution suggesting that HBV/A1, but not HBV/E, was imported from Africa during the slave trade, and further supporting the hypothesis that HBV/E has emerged recently in West Africa (<150 years). Potential origins of 'European' HBV/A2 and HBV/D3, 'Amerindian' HBV/F, and HBV/D4 strains are also discussed. Such HBV genetic diversity, beyond its epidemiological interest, may have a clinical impact on the natural history of HBV infection in Martinique.

A wide variety of commercial assays is available for the detection of hepatitis B surface antigen (HBsAg). Clearly, the sensitivity of an assay to detect a variant is dependent on the anti-HBs usage. Thus, it is not surprising that there are examples of variants that cannot be detected by all assays. Data from Europe, Asia and Africa about HBsAg variants which are not recognized by either monoclonal or polyclonal antibodies specific for wild-type group 'a' determinant, but positive by DNA polymerase chain reaction (PCR) in chronic patients and from vaccinated children are increasing. This would impose a challenge for public health issues of hepatitis B virus. In this review we tried to summarize the discrepancies between results of HBsAg assays and to explain some rationales for these inconsistencies., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Unlabelled: The origin of hepatitis B virus (HBV) infection in humans and other primates remains largely unresolved. Understanding the origin of HBV is crucial because it provides a framework for studying the burden, and subsequently the evolution, of HBV pathogenicity with respect to changes in human population size and life expectancy. To investigate this controversy we examined the relationship between HBV phylogeny and genetic diversity of modern humans, investigated the timescale of global HBV dispersal, and tested the hypothesis of HBV-human co-divergence. We find that the global distribution of HBV genotypes and subgenotypes are consistent with the major prehistoric modern human migrations. We calibrate the HBV molecular clock using the divergence times of different indigenous human populations based on archaeological and genetic evidence and show that HBV jumped into humans around 33,600 years ago; 95% higher posterior density (HPD): 22,000-47,100 years ago (estimated substitution rate: 2.2 × 10(-6) ; 95% HPD: 1.5-3.0 × 10(-6) substitutions/site/year). This coincides with the origin of modern non-African humans. Crucially, the most pronounced increase in the HBV pandemic correlates with the global population increase over the last 5,000 years. We also show that the non-human HBV clades in orangutans and gibbons resulted from cross-species transmission events from humans that occurred no earlier than 6,100 years ago., Conclusion: Our study provides, for the first time, an estimated timescale for the HBV epidemic that closely coincides with dates of human dispersals, supporting the hypothesis that HBV has been co-expanding and co-migrating with human populations for the last 40,000 years. (HEPATOLOGY 2013)., (Copyright © 2012 American Association for the Study of Liver Diseases.)

Background: Hepatitis B virus (HBV) infection is one of the most prevalent viral infections in humans and represents a serious public health problem. In Colombia, our group reported recently the presence of subgenotypes F3, A2 and genotype G in Bogotá. The aim of this study was to characterize the HBV genotypes circulating in Quibdó, the largest Afro-descendant community in Colombia. Sixty HBsAg-positive samples were studied. A fragment of 1306 bp (S/POL) was amplified by nested PCR. Positive samples to S/POL fragment were submitted to PCR amplification of the HBV complete genome., Findings: The distribution of HBV genotypes was: A1 (52.17%), E (39.13%), D3 (4.3%) and F3/A1 (4.3%). An HBV recombinant strain subgenotype F3/A1 was found for the first time., Conclusions: This study is the first analysis of complete HBV genome sequences from Afro-Colombian population. It was found an important presence of HBV/A1 and HBV/E genotypes. A new recombinant strain of HBV genotype F3/A1 was reported in this population. This fact may be correlated with the introduction of these genotypes in the times of slavery.

Aim: To screen hepatitis B virus (HBV) genotypes and associated basal core promoter (BCP; T1762A/A1764) and precore (PC; A1896) mutations among the 100 HBV surface antigen (HBsAg) positive voluntary blood donors in France., Methods: HBV genotypes were determined by using direct sequence analysis. Three methods were used to detect G1896A mutation: non-commercial real-time PCR (PCRTR°, line probe assay (InnoLiPA HBV PreCore, INNOGENETICS(®)) and direct sequencing of precore gene. HBV viral load was quantified with two commercial real-time PCR (COBAS(®) AmpliPrep/COBAS(®) TaqMan(®) HBV Test/Roche and Real Time HBV/M2000/Abbott)., Results: The mean age of donors was 30 (18-64). Patients were from Africa (42%), Europa (50%), and Asia (8%). HBV/D was the most predominant (37%) genotype followed by HBV/A (31%) and HBV/E (22%). PC and BCP mutants were found in 57% with Inno-LIPA HBV test and 59% with both PCRTR and sequencing methods. A significant difference in the viral load of blood donors with wild and PC mutants was observed with the Taqman Cobas real time PCR (3,19 Log(10) UI/ml versus 4,93 Log(10) UI/ml, p < 0.05). Precore phenotype determination was in agreement with the three PC mutation detection methods in 56% of cases., Conclusions: Non-Caucasian genotype E was present in the French blood donors. PC mutation was more common than BCP mutations in this study. As HBV infected blood donors were more often asymptomatic carriers, we could speculate that the G1896A mutation may favour the asymptomatic state, supporting previous observations., (Copyright © 2010 Elsevier Masson SAS. All rights reserved.)

Background and Objectives: This study was conducted by the International Consortium for Blood Safety (ICBS) to identify high-quality test kits for detection of hepatitis B virus (HBV) surface antigen (HBsAg) for the benefit of developing countries., Materials and Methods: The 70 HBsAg test kits from around the world were evaluated comparatively for their clinical sensitivity, analytical sensitivity, sensitivity to HBV genotypes and HBsAg subtypes, and specificity using 394 (146 clinical, 48 analytical and 200 negative) ICBS Master Panel members of diverse geographical origin comprising the major HBV genotypes A-F and the HBsAg subtypes adw2,4, adr and ayw1-4., Results: Seventeen HBsAg enzyme immunoassay (EIA) kits had high analytical sensitivity <0.13 IU/ml, showed 100% diagnostic sensitivity, and were even sensitive for the various HBV variants tested. An additional six test kits had high sensitivity (<0.13 IU/ml) but missed HBsAg mutants and/or showed reduced sensitivity to certain HBV genotypes. Twenty HBsAg EIA kits were in the sensitivity range of 0.13-1 IU/ml. The other eight EIAs and the 19 rapid assays had analytical sensitivities of 1 to >4 IU/ml. These assays were falsely negative for 1-4 clinical samples and 17 of these test kits showed genotype dependent sensitivity reduction. Analytical sensitivities for HBsAg of >1 IU/ml significantly reduce the length of the HBsAg positive period which renders them less reliable for detecting HBsAg in asymptomatic HBV infections. Reduced sensitivity for HBsAg with genetic diversity of HBV occurred with genotypes/subtypes D/ayw3, E/ayw4, F/adw4 and by S gene mutants. Specificity of the HBsAg assays was >or=99.5% in 57 test kits and 96.4-99.0% in the remaining test kits., Conclusion: Diagnostic efficacy of the evaluated HBsAg test kits differed substantially. Laboratories should therefore be aware of the analytical sensitivity for HBsAg and check for the relevant HBV variants circulating in the relevant population.

In Haiti, >90% of the population descended from African slaves. Of 7,147 Haitian pregnant women sampled, 44% of hepatitis B virus (HBV) infections were caused by genotype A1, which today is found mainly in eastern Africa. Twenty percent belong to a rare subgenotype, A5, which has been found only in the former Bight of Benin, a former primary slave trading post. Haitian A subgenotypes appear to have separated early from the African subgenotypes; the most prevalent genotype and subgenotype in West Africa today (E and A3, respectively) are rare in Haiti. This difference indicates that the dominant subgenotypes in Africa emerged in the general population only after the slave trade and explains the low genetic diversity of genotype E. The high prevalence of HBV genotype E in much of Africa further suggests that HBV hyperendemicity is a recent phenomenon, probably resulting from extensive use of unsafe needles.

Hepatitis B virus (HBV) is highly endemic throughout sub-Saharan Africa. One of the two genotypes A and E dominates in most countries. With several subgenotypes and variants, genotype A is more diverse in Africa (4.00%) than in the rest of the world (2.96%), suggesting an African origin and a long history on the continent. Despite the African slave trade, genotype E has only sporadically been found within the Americas, indicating that this genotype was introduced only during the past 200 years into the general African population. A short history for this genotype in Africa is also supported by its conspicuously low genetic diversity (1.75%), which contrasts, however, with its excessively high HBsAg prevalence and its extensive spread throughout the vast West-African genotype E crescent. We discuss the spread and routes of transmission of genotype E and suggest that the distribution and current high prevalence levels of HBV (genotype E) in Africa are the result of the extensive use of unsafe needles, potentially solving the current African genotype E puzzle and shedding new light on the high HBV prevalence in Africa.

Hepatitis B viruses (HBVs) represent a serious public health problem affecting 350 to 400 million HBV carriers worldwide. The virus does not exclusively infect humans, but can also be found in non-human primates as in the families Hominidae (chimpanzee, gorilla, orangutan) and Hylobatidae (gibbon), which are distributed over Africa (chimpanzee and gorilla) and Southeast Asia (orangutan and gibbon), the endemic areas of human HBV. The prevalence of asymptomatic HBV carriers reaches in gibbons 23-33% and in orangutans 15%. The genome organization of non-human primate HBVs is nearly identical to that of human HBVs. Because of this close similarity, the question of cross-transmission of HBV between species has arisen. There are many data on cross-transmission of human HBVs to the non-human primates. However, a cross-transmission of HBVs from non-human primates to humans has not been reported yet. Using more advanced diagnostic methods, the non-human primates have increasingly been identified as a reservoir of several viruses such as lymphocryptoviruses, Cercopithecine herpesvirus 1 (CeHV-1), Simian immunodeficiency virus (SIV), Simian foamy virus (SFV), and HBVs. Thus veterinarians, zookeepers, or people in close contact with non-human primates may potentially become infected with those viruses causing severe diseases. Enhanced awareness of prevalence, genetic relatedness and evolution of non-human primate HBVs will help prevent further spread and cross-transmission of these viruses between humans and non-human primates.

Background: In sub-Saharan Africa, genotype E is the predominant genotype throughout a vast region spanning from Senegal to Namibia and extending to the Central African Republic in the East. Despite its wide geographic distribution and the high prevalence throughout this genotype E crescent, this genotype has a very low genetic diversity., Objectives: Here we review our current understanding of genotype E reanalysing all currently available sequences of the S gene and the complete genome., Results: Phylogenetic analysis of the complete genome sequences confirmed a previously suggested South-West/Central African cluster and several lineages of West African sequences. The overall mean genetic distance was 1.71%, with the more Southern countries of the genotype E crescent exhibiting lower distances than the Northern countries., Conclusions: Genotype E seems to have a longer natural history in the Northern part of the genotype E crescent than in the Southern countries. As genotype E is essentially absent from the Americas despite the Afro-American slave trade until at least the beginning of the 19th century, genotype E strains may have been introduced into the general African population only within the past 200 years. How the virus may have spread throughout the genotype E crescent warrants further investigation.

Hepatitis B virus (HBV) is the leading cause of chronic liver disease and liver-related death worldwide, with the majority of these cases occurring in areas of Africa and Asia where HBV prevalence is high. Many of the countries that are affected by hepatitis B are also affected by a high HIV burden, leading to frequent HIV/HBV co-infection. The consequences of co-infection, including increased liver-related morbidity and mortality, increased hepatitis B viral replication, immune reconstitution to HBV in the setting of antiretroviral therapy, and hepatotoxicity from antiretroviral drugs, are especially important in regions with expanding antiretroviral programmes. Little data, however, are available on HIV/HBV co-infection from regions with high chronic hepatitis B prevalence. This Review discusses the epidemiology, natural history, pathogenesis, and management of HIV/HBV co-infection from these areas. Topics for future research relevant to HIV/HBV co-infection in Africa and Asia are also highlighted.

Background: Viral hepatitis B and C are a major health problem worldwide. The prevalence of these diseases varies throughout the world. In Iceland, the incidence of hepatitis B and C has increased in recent years. At the same time, the number of immigrants from countries where viral hepatitis is endemic, has also increased. The aim of this study was to investigate the epidemiology of hepatitis B and C among immigrants in Iceland., Material and Methods: Immigrants from outside the European Economic Area (EEA) were screened for hepatitis B and C. Medical records for the years 2000-2002 were reviewed for country of origin, viral serology and liver transaminases. Information was gathered from the State Epidemiologist's central registry of notifiable diseases and from the Icelandic Directorate of Immigration on the number of residence permits issued., Results: 70% of all immigrants from countries outside the EEA during the study period were included in the study. Blood samples were obtained from 2946 immigrants. 83 (2.8%) had hepatitis B and 24 (0.8%) had hepatitis C. Prevalence of hepatitis B was highest among immigrants from Africa,11/171 (6.4%; 95% CI: 3.3-11.2%) and hepatitis C among immigrants from Eastern Europe, 16/1502 (1.1%; 95% CI: 0.6-1.7%). 482 (16%) had serological markers of previous hepatitis B infection. Of all registered cases of hepatitis B, immigrants were 56% and of hepatitis C 10%., Conclusions: 1. Majority of those diagnosed with hepatitis B during the study period were immigrants. 2. Among immigrants, hepatitis B was more prevalent than hepatitis C. 3) The high prevalence of hepatitis B justifies screening for the disease in this population.

Hepatitis B virus (HBV) is a major cause worldwide of liver disease, including hepatocellular carcinoma. There are eight known genotypes (A-H), of which genotype A has been divided into two subtypes: A2, prevalent in Europe, and A1, which is prevalent in sub-Saharan Africa, but also occurs in southern Asia. In this study, which includes 14 new complete genomes of non-European genotype A HBV, it was found that West African strains seem to constitute a new subgroup, A3. The high degree of genetic diversity within Africa indicates that genotype A originates from Africa. Based on a 2 % genetic distance between Asian and Somali sequences, it seems that the A1 subtype has spread from East Africa to southern Asia during the last 1000-2000 years. Moreover, it is proposed here that the A2 subtype originates from southern Africa and was imported to Europe around 500 years ago or later. The finding of T-1809/1812 close to the precore start codon and T-1862 and A-1888 in the precore region in HBV e antigen-positive children with signs of a mimimal immune response indicates that these substitutions are stable variants, rather than mutations emerging during infection in individual carriers.

Hepatitis B virus (HBV) has eight genotypes which have distinct geographical distributions. Studies comparing differences in the clinical outcomes of infections caused by strains with genotype-related variations in the HBV genome have largely compared genotypes B and C and genotypes A and D but not all four genotypes. The present study included 196 HBV-infected patients attending an infectious diseases outpatient clinic in Sweden. The age and geographic origin, liver function, HBeAg and anti-HBe status, and the presence or absence of HBV DNA were analyzed for each patient. HBV DNA was detected in 144 patients, and the HBV genotype and the core promoter and precore sequences were determined for the isolates from 101 of these patients. Among the patients who might be considered most likely to be nonviremic, namely, anti-HBe-positive HBV carriers with normal alanine aminotransferase (ALT) levels, 65% had detectable HBV DNA and were thus viremic. Among the viremic patients, HBeAg-positive patients were more likely to have elevated ALT levels than anti-HBe-positive patients. HBV genotypes A to F were represented in the study, and their distributions coincided accurately with the origin of the patient. A significantly higher number of genotype D-infected patients were anti-HBe positive and had elevated ALT levels (42% of genotype D-infected patients but 0% of patients infected with genotypes B and C). Genotype D strains with mutations in the core promoter and precore regions were significantly correlated with elevated ALT levels in the patients. The differences were not age related. Therefore, in this large-scale cross-sectional study, genotype D appears to be associated with more active disease.

Hepatitis B virus (HBV) genotypes in three different communities in the Republic of Yemen with and without significant African links were studied. The subjects included indigenous Yemeni blood donors (n = 987), Africans who had settled down in Yemen for several generations (n = 97) and Soqotrans living on an island in the Indian Ocean close to the African coast (n = 99). Phylogenetic analysis of HBV surface region sequences showed the presence of two major genotypes; A and D: sequences from the blood donors were all genotype D (17/17); those from Africans residing in Yemen were predominantly genotype D (7/8) although one sequence was genotype A; whereas a mixture of genotype A and D was found among the Soqotrans (5/8 and 3/8 respectively). Genotype A sequences were associated with higher viral load, but the difference was not statistically significant. Human migration and international travel, may lead to an interaction between HBV genotypes. The Republic of Yemen is at a location where genotypes A and D meet. The results from this study suggest that genotype A is found only in communities with continuing African links and that genotype D remains the dominant genotype in settled populations. More studies are needed to examine possible long-term changes in HBV genotypes in this region., (Copyright 2004 Wiley-Liss, Inc.)

Complete nucleotide sequences of 19 hepatitis B virus (HBV) isolates of genotype A (HBV/A) were determined and analysed along with those of 20 previously reported HBV/A isolates. Of the 19 HBV/A isolates, six including three from Japan and three from the USA clustered with the 14 HBV/A isolates from Western countries. The remaining 13 isolates including four from The Philippines, two from India, three from Nepal and four from Bangladesh clustered with the six HBV/A isolates reported from The Philippines, South Africa and Malawi. Due to distinct epidemiological distributions, genotype A in the 20 HBV isolates was classified into subtype Ae (e for Europe), and that in the other 19 into subtype Aa (a for Asia and Africa) provisionally. The 19 HBV/Aa isolates had a sequence variation significantly greater than that of the 20 HBV/Ae isolates (2.5+/-0.3 % vs 1.1+/-0.6 %, P<0.0001); they differed by 5.0+/-0.4 % (4.1-6.4 %). The double mutation (T1762/A1764) in the core promoter was significantly more frequent in HBV/Aa isolates than in HBV/Ae isolates (11/19 or 58 % vs 5/20 or 25 %, P<0.01). In the pregenome encapsidation (epsilon) signal, a point mutation from G to A or T at nt 1862 was detected in 16 of the 19 (84 %) HBV/Aa isolates but not in any of the 20 HBV/Ae isolates, which may affect virus replication and translation of hepatitis B e antigen. Subtypes Aa and Ae of genotype A deserve evaluation for any clinical differences between them, with a special reference to hepatocellular carcinoma prevalent in Africa.

Despite a reduction in newly acquired hepatitis B virus (HBV) infections since the mid-1980s, HBV remains an important cause of liver disease in the U.S. We report the prevalence of chronic HBV infection in a U.S. community and describe demographic and clinical characteristics. The Rochester Epidemiology Project records healthcare encounters of residents of Olmsted County, Minnesota. For all cases with a potential diagnosis of hepatitis B in this database, complete medical records were reviewed to identify subjects who met the inclusion criteria, i.e., a clinician diagnosis of chronic HBV infection and a laboratory record of positive hepatitis B surface antigen (HBsAg). There were 191 residents with chronic HBV infection in the community, consisting of 53% Asian, 29% African, 13% Caucasian, and 5% other or unknown race. The overall age- and sex-adjusted prevalence of HBV in this community was 0.15% in 2000. The race-specific prevalence was highest among Asians (2.1%), followed by African Americans (1.9%). The prevalence among Caucasians was 0.02%. Overall, 86% were born outside the U.S., 98% of whom were non-Caucasian. A total of 131 residents were tested for HBV replicative status, of whom 27% had viral replication. Of those tested for aminotransferases (n = 184), 28% had an abnormal value at least once. In a multivariable regression analysis, replicative status was the most influential (odds ratio [OR] = 5.98, P <.01) factor associated with abnormal aminotransferase values, followed by male gender (OR = 3.69) and age greater than 40 years (OR = 2.32 per decade). In conclusion, in this Midwestern community, chronic HBV infection was predominantly seen in immigrants from endemic parts of the world.

Infection with hepatitis B virus (HBV) has been detected in human populations throughout the world, as well as in a number of ape species (Pan troglodytes, Gorilla gorilla, gibbons [Nomascus and Hylobates species] and Pongo pygmaeus). To investigate the distribution of naturally occurring HBV infection in these species and other African Old World monkey species (Cercopithecidae), we screened 137 plasma samples from mainly wild caught animals by polymerase chain reaction (PCR) using several of highly conserved primers from the HB surface (HBs) gene, and for HBs antigen (HBsAg) by ELISA. None of the 93 Cercopithecidae screened (6 species) showed PCR or serology evidence for HBV infection; in contrast 2 from 8 chimpanzees and 5 from 22 gibbons were PCR-positive with each set of primers. Complete genome sequences from each of the positive apes were obtained and compared with all previously published complete and surface gene sequences. This extended phylogenetic analysis indicated that HBV variants from orangutans were interspersed by with HBV variants from southerly distributed gibbon species (H. agilis and H. moloch) occupying overlapping or adjacent habitat ranges with orangutans; in contrast, HBV variants from gibbon species in mainland Asia were phylogenetically distinct. A geographical rather than (sub)species association of HBV would account for the distribution of HBV variants in different subspecies of chimpanzees in Africa, and explain the inlier position of the previously described lowland gorilla sequence in the chimpanzee clade. These new findings have a number of implication for understanding the origins and epidemiology of HBV infection in non-human primates.

An enzyme-linked immunosorbent assay (ELISA) has been described for serological determination of hepatitis B virus genotypes, using monoclonal antibodies (mAb) against seven distinct epitopes (b, m, k, s, u, f and g) on the preS2-region products of hepatitis B surface antigen (HBsAg). The usefulness of this method for serological detection of genotype E, however, was theoretical, because no HBsAg samples of this genotype were included in the original test panel. Moreover, the predicted serotype of genotype E (bksufg) closely resembled that of genotype D (bksu, bksuf or bksug). Four HBsAg samples of genotype E were tested by the original described ELISA. The epitope g, predicted to be present in these samples by amino acid sequences, was not detected when HBsAg of genotype E was captured on a solid phase by mAb to the common determinant 'a' of HBsAg and then reacted with mAb to g (5156) labeled with horseradish peroxidase. However, the four examples of HBsAg of genotype E were captured by mAb 5156 to g on a solid phase; they were then detected by labeled mAb to the common determinant 'a'. Since epitopes f and g co-occurred on HBsAg of genotype E, HBsAg samples of this genotype were also detected, by 'sandwiching' them between immobilized mAb to g and labeled mAb to f. By contrast, HBsAg of genotype D in 90 sera was not reactive when sandwiched between mAb to f and g. Thus, this modified ELISA enables the serological determination of all six genotypes of HBsAg and, by inference, of hepatitis B virus.

Hepatitis B and C are, and will remain for some time, major health problems in Egypt and the entire continent of Africa. Both infections can lead to an acute or silent course of liver disease, progressing from liver impairment to cirrhosis and decompensated liver failure or hepatocellular carcinoma (HCC) in a 20-30 year period. In addition, hepatitis B and C infection rates differ in different settings, and prognosis may be worse in conjunction with schistosomiasis in Egypt, malaria in Sudan and human immunodeficiency virus (HIV) in other African populations. Unlike hepatitis B virus (HBV), for which the prospects for controlling the spread of infection by vaccination are promising, prospects for development of an effective vaccine against hepatitis C virus (HCV) are limited. As well as screening of blood for transfusion and using sterile needles for injection, preventive measures should be undertaken to reduce the risk of contact (often described as community-acquired infection). Until more is known about the unidentified routes of transmission in tropical and subtropical settings it will be difficult to be specific about the kind of measures which may be effective. Success may largely depend on changing habits within the population. Prevention should be the main goal of current efforts until low-cost, effective therapies become available.