Performance evaluation of 70 hepatitis B virus (HBV) surface antigen (HBsAg) assays from around the world by a geographically diverse panel with an array of HBV genotypes and HBsAg subtypes

Hepatitis B Virus Genotype H: Epidemiological, Molecular, and Clinical Characteristics in Mexico

The hepatitis B virus (HBV), comprising of ten genotypes (A-J), has been a silent threat against humanity, constituting a public health problem worldwide. In 2016, the World Health Organization set forth an impressive initiative for the global elimination of viral hepatitis by 2030. As the target date approaches, many nations, particularly in the Latin American region, face challenges in designing and implementing their respective elimination plan. This review aimed to portray the state of knowledge about the epidemiological, molecular, and clinical characteristics of HBV genotype H (HBV/H), endemic to Mexico. PubMed, Scopus, Web of Science, and Google Scholar were searched to compile scientific literature over 50 years (1970-2022). A total of 91 articles were organized into thematic categories, addressing essential aspects such as epidemiological data, risk factors, HBV genotype distribution, HBV mixed infections, clinical characteristics, and vaccination. The prevalence and its associated 95% confidence interval (95% CI) were estimated using the Metafor package in R programming language (version 4.1.2). We provide insights into the strengths and weaknesses in diagnostics and prevention measures that explain the current epidemiological profile of HBV/H. Training, research, and awareness actions are required to control HBV infections in Mexico. These actions should contribute to creating more specific clinical practice guides according to the region's characteristics. Mexico's elimination plan for HBV will require teamwork among the government health administration, researchers, physicians, specialists, and civil society advocates to overcome this task jointly.

Performance evaluation of in vitro diagnostic kits for hepatitis B virus infection using the regional reference panel of Japan

BACKGROUND

Hepatitis B virus (HBV) infection is a global public health concern. Precise and sensitive detection of viral markers, including HBV DNA and HBs antigen (Ag), is essential to determine HBV infection.

METHODS

The sensitivities and specificities of 5 HBV DNA and 14 HBsAg kits were evaluated using World Health Organization International Standards (WHO IS) and the Regional Reference Panel (RRP) consisting of 64 HBsAg-negative and 80 HBsAg-positive specimens.

RESULTS

All 5 HBV DNA kits detected HBV DNA in the WHO IS at a concentration of 10 IU/mL. The sensitivity and specificity to the RRP were 98.8-100% and 96.9-100%, respectively. HBV DNA titers were well correlated among the 5 kits regardless of HBV genotype. However, discordance of the HBV DNA titer was found in 5 specimens measured by CAP/CTM HBV v2.0. Among 12 automated HBsAg kits, the minimum detectable concentrations in the WHO IS varied from 0.01 to 0.1 IU/mL. Two lateral flow assays were positive for WHO IS concentrations greater than or equal to 1.0 and 0.1 IU/mL, respectively. When analyzed by the RRP, 12 automated kits exhibited a sensitivity of 98.8-100%, and 2 lateral flow assays showed sensitivities of 93.8% and 100%. The specificities of HBsAg kits were 100%. In the quantification of HBsAg, some kits showed a poor correlation of measurements with each other and showed up to a 1.7-fold difference in the regression coefficient of HBsAg titers. There were variations in the correlations of measurements among HBsAg kits when analyzed by genotype.

CONCLUSIONS

Five HBV DNA kits showed sufficient sensitivity and specificity to determine HBV infection. HBV DNA titers were compatible with each other irrespective of HBV genotypes. HBsAg kits had enough sensitivity and specificity to screen for HBV infection. One of the lateral flow assays had a nearly equivalent sensitivity to that of the automated HBsAg kit. HBsAg titers quantified by the evaluated kits were not compatible across the kits. Genotype-dependent amino acid variations might affect the quantification of HBsAg titers.

A roadmap for serum biomarkers for hepatitis B virus: current status and future outlook

Globally, 296 million people are infected with hepatitis B virus (HBV), and approximately one million people die annually from HBV-related causes, including liver cancer. Although there is a preventative vaccine and antiviral therapies suppressing HBV replication, there is no cure. Intensive efforts are under way to develop curative HBV therapies. Currently, only a few biomarkers are available for monitoring or predicting HBV disease progression and treatment response. As new therapies become available, new biomarkers to monitor viral and host responses are urgently needed. In October 2020, the International Coalition to Eliminate Hepatitis B Virus (ICE-HBV) held a virtual and interactive workshop on HBV biomarkers endorsed by the International HBV Meeting. Various stakeholders from academia, clinical practice and the pharmaceutical industry, with complementary expertise, presented and participated in panel discussions. The clinical utility of both classic and emerging viral and immunological serum biomarkers with respect to the course of infection, disease progression, and response to current and emerging treatments was appraised. The latest advances were discussed, and knowledge gaps in understanding and interpretation of HBV biomarkers were identified. This Roadmap summarizes the strengths, weaknesses, opportunities and challenges of HBV biomarkers.

Clinical utility of the 'Determine HBsAg' Point-of-Care Test for Diagnosis of Hepatitis B Surface Antigen in Africa

INTRODUCTION

Chronic infection with hepatitis B virus (HBV) is a leading cause of morbidity and death, especially in sub-Saharan Africa (sSSA), where approximately 60 million adults are infected. More than 90% of these patients are unaware of their HBV status.

AREAS COVERED

Scaling-up of HBV screening programs in SSA are essential to increase diagnosis, linkage to care and access to treatment, and will ultimately reduce HBV disease burden to achieve WHO hepatitis elimination targets. Such scale up will rely on inexpensive rapid point-of-care (POC) tests, especially in remote areas where gold standard serological assays are not routinely available. This review discusses the diagnostic performance and clinical utility of the Determine™ (Abbott, USA) hepatitis B surface Antigen (HBsAg) POC test for improving HBV screening in SSA, in light with others available HBsAg rapid tests.

EXPERT OPINION

The Determine™ HBsAg POC test has demonstrated relatively good diagnostic accuracy at the low cost, in the African field and laboratory and should be used for large scale mass screening of HBV infection in Africa.

[Safety of blood and blood products: test methods for the detection of hepatitis B, C, and E virus]

Infections with hepatitis B, C, and E virus (HBV, HCV, and HEV) can be transmitted via blood and cause severe acute or chronic liver infections. To ensure the safety of blood donations and protect recipients from virus transmissions, blood donations in Germany are tested for viral genomes using nucleic acid amplification techniques (NATs) as well as for viral antigens and antibodies by serological testing. This article describes the relevant regulations on the safety of blood and blood products in Germany and the various screening methods. The safety of blood products is assessed.Currently used NAT methods for detection of hepatitis viruses are based either on polymerase chain reaction (PCR) or isothermal methods such as transcription-mediated amplification (TMA), which enable a highly sensitive detection of viral infections and thereby contribute to the reduction of the diagnostic window. Antigen tests for the detection of viral surface protein of hepatitis B virus in blood donations were introduced in the 1970s in order to prevent potential transmissions. Since the introduction of mandatory testing for HCV-specific antibodies in 1992, HCV NAT testing in 1999, anti-HBc antibody testing in 2006, and the non-mandatory HBV NAT, which is voluntarily performed by most of the blood establishments, blood safety has increased tremendously. Only a few isolated cases of transfusion-transmitted infections in the early window period have been reported since. The success of the recent introduction of mandatory HEV NAT testing in 2020 will have to be assessed in the upcoming years. Besides blood donor screening, the system for blood safety in Germany is supplemented by additional measures for donor selection and pathogen inactivation.

A Study on the Evaluation of the Effect of Exercise on the Treatment of Chronic Diseases Based on a Digital Human Movement Model

The aim of this study was to summarise the therapeutic effects of exercise interventions for common chronic diseases and to analyse the scope of application and problems of various exercise treatment protocols, with a view to guiding clinical practice and providing references for subsequent research. To this end, this paper describes how to extract feature parameters for gait analysis based on a digital human motion model. In-depth descriptions of the extraction algorithms for spatiotemporal features, centre-of-mass movement features, joint mobility, and joint contact forces are presented, and the reliability of the knee contact force extraction algorithm is analysed in particular. To analyse the effect of exercise on the treatment of chronic diseases, 50 cases of elderly chronic disease patients collected from the community were selected and subjected to healthy exercise for 1 year, before and after the healthy exercise. After the exercise, the elderly chronic disease patients' blood pressure, lipid, and blood glucose attainment rates, chronic diseases, and knowledge of nonpharmacological treatments were significantly higher, with statistically significant differences compared to the preexercise period (P < 0.05).

Comparative evaluation of ADVIA Centaur® XP chemiluminescence system for screening of HBV, HCV, HIV and syphilis in Indian blood donors

BACKGROUND

The introduction of chemiluminescent immunoassay (CLIA) in blood donor screening has led to a gradual replacement of enzyme-linked-immunosorbent assay (ELISA) as the former offers automation, higher sensitivity and lower turn-around-time. However, only a few CLIA platforms are used for blood donor screening in India. The present study evaluated one such newer platform viz., Adiva Centaur XP CLIA for screening of HBV, HCV, HIV and syphilis.

MATERIAL AND METHODS

Prospective comparative study wherein 4843 whole blood donors were screened for HBsAg, Anti-HCV, HIV Ag-Ab and Anti-treponemal antibodies in both Advia Centaur XP and Architect i2000SR platforms. Additional tests were performed in samples which were reactive in only one of the platforms. The sensitivity, specificity, positive predictive value, negative predictive value, accuracy, false positive rate and false negative rate of both the platforms were compared. Kappa coefficient was calculated to determine the agreement between the testing platforms.

RESULTS

The sensitivity of Advia Centaur platform for HBV, HCV, HIV and syphilis detection were 94.9 %, 100 %, 100 % and 100 % respectively as compared to 96.6 %, 100 %, 100 % and 100 % in Architect i2000SR platform. The specificity of both the platforms were 99.8-99.9 % for all the four tests. The agreement between the two platforms was almost perfect for HBV, HCV and syphilis testing; and fair for HIV testing.

CONCLUSION

The Advia Centaur CLIA platform was found to be comparable with the Architect CLIA platform for blood donor screening. Unexpected finding was the occurrence of HBV false negatives in both the platforms, possibly due to HBsAg mutations.

Alcohol drinking and risks of liver cancer and non-neoplastic chronic liver diseases in China: a 10-year prospective study of 0.5 million adults

BACKGROUND

Alcohol consumption is an important risk factor for hepatic neoplastic and non-neoplastic diseases. Questions remain, however, about the relevance to disease risk of drinking patterns and alcohol tolerability, which differ appreciably between Chinese and Western populations.

METHODS

The prospective China Kadoorie Biobank included 512,715 adults (41% men) aged 30-79 years recruited from ten areas during 2004-2008, recording alcohol intake, drinking patterns, and other characteristics. After median 10 years' follow-up, 2531 incident liver cancer, 2040 liver cirrhosis, 260 alcoholic liver disease (ALD), and 1262 non-alcoholic fatty liver disease (NAFLD) cases were recorded among 492,643 participants without prior cancer or chronic liver disease at baseline. Cox regression was used to estimate adjusted hazard ratios (HR) relating alcohol intake and drinking patterns to each disease.

RESULTS

Overall, 33% of men and 2% of women drank alcohol regularly (i.e. at least weekly) at baseline. Among male current regular drinkers, alcohol consumption showed positive dose-response associations with risks of several major chronic liver diseases, with HRs per 280 g/week (i.e. around four drinks/day) higher usual alcohol intake of 1.44 (95% CI 1.23-1.69) for liver cancer (n = 547), 1.83 (1.60-2.09) for liver cirrhosis (n = 388), 2.01 (1.77-2.28) for ALD (n = 200), 1.71 (1.35-2.16) for NAFLD (n = 198), and 1.52 (1.40-1.64) for total liver disease (n = 1775). The association with ALD appeared stronger among men reporting flushing (i.e., with low alcohol tolerance). After adjustment for the total amount of weekly alcohol consumption, daily drinkers had significantly increased risk of ALD (2.15, 1.40-3.31) compared with non-daily drinkers, and drinking without meals was associated with significantly greater risks of liver cancer (1.32, 1.01-1.72), liver cirrhosis (1.37, 1.02-1.85), and ALD (1.60, 1.09-2.33) compared with drinking with meals. Female current regular drinkers had significantly higher risk of ALD, but not other liver diseases, than female abstainers.

CONCLUSIONS

In Chinese men, alcohol intake was associated with significantly increased risks of several major chronic liver diseases, and certain drinking patterns (e.g. drinking daily, drinking without meals) may further exacerbate the disease risks.

Detection of the serological markers hepatitis B virus surface antigen (HBsAg) and hepatitis B core IgM antibody (anti-HBcIgM) in the diagnosis of acute hepatitis B virus infection after recent exposure

The serological diagnosis of acute hepatitis B virus (HBV) infection after recent exposure has been established by the hepatitis B virus surface antigen (HBsAg) and anti-hepatitis B core IgM antibody (anti-HBcIgM) detection in serum, sometimes accompanied by the detection of hepatitis B "e" antigen (HBeAg). Despite this characteristic serological profile, misdiagnosis can occur in cases of unexpected or atypical behavior of the serological markers in the bloodstream, or if the true meaning of its expression is not properly investigated, or even if there is a possibility of interference from factors not necessarily linked to the infectious process, in the detection of these markers. This review discusses the influence of these variables on laboratory results for these two serological markers and, therefore, the potential risk of these variables compromising the correct diagnosis of acute infection after recent HBV exposure.

Nanobiosensing based on optically selected antibodies and superparamagnetic labels for rapid and highly sensitive quantification of polyvalent hepatitis B surface antigen

Hepatitis B surface antigen (HBsAg) is the most clinically relevant serological marker of hepatitis B virus (HBV) infection. Its detection in blood is extremely important for identification of asymptomatic individuals or chronic HBV carriers, screening blood donors, and early seroconversion. Rapid point-of-care HBsAg tests are predominantly qualitative, and their analytical sensitivity does not meet the requirements of regulatory agencies. We present a highly sensitive lateral flow assay based on superparamagnetic nanoparticles for rapid quantification (within 30 min) of polyvalent HBsAg in serum. The demonstrated limit of detection (LOD) of 80 pg mL^-1 in human serum is better than both the FDA recommendations for HBsAg assays (which is 0.5 ng mL^-1) and the sensitivity of traditional laboratory-based methods such as enzyme linked immunosorbent assays. Along with the attractive LOD at lower concentrations and the wide linear dynamic range of more than 2.5 orders, the assay features rapidity, user-friendliness, on-site operation and effective performance in the complex biological medium. These are due to the combination of the immunochromatographic approach with a highly sensitive electronic registration of superparamagnetic nanolabels over the entire volume of a 3D test structure by their non-linear magnetization and selection of optimal antibodies by original optical label-free methods. The developed cost-efficient bioanalytical technology can be used in many socially important fields such as out-of-lab screening and diagnosis of HBV infection at a point-of-demand, especially in hard-to-reach or sparsely populated areas, as well as highly endemic regions.

Challenges in transfusion-transmitted infection screening in Sub-Saharan Africa

In Sub-Saharan Africa, high clinical demand for transfusion faces endemic bloodborne infections and limited resources. Blood screening for transfusion-transmitted bloodborne pathogens is the cornerstone of blood safety. Although there have been substantial improvements over the years, challenges in transfusion-transmitted infection screening that have been identified repeatedly long ago still need to be addressed. Affordability and sustainability of state-of-the-art quality assessed serological and molecular assays, and associated confirmation strategies remain of real concern. In addition, limited resources and infrastructures hamper the development of adequate facilities, quality management, and staff qualification, and exacerbate shortage of reagents and equipment maintenance. It is also important to maintain effort in constituting pools of repeat voluntary non-remunerated donors. Alternative strategies for blood screening that take into account local circumstances might be desirable but they should rely on appropriate field evaluation and careful economic assessment rather than dogma established from high-resource settings.

Field performance of HBsAg rapid diagnostic tests in rural Ethiopia

Point-of-care rapid diagnostic tests (POC-RDTs) are widely used to screen and diagnose hepatitis B virus (HBV) infection and are often the only available diagnostic tools in resource-limited settings. The aim of this study was to evaluate the validity of three hepatitis B surface antigen (HBsAg) POC-RDTs (Healgen®, Advanced Quality™ and Determine™) in an area with high prevalence of HBV in eastern Ethiopia. Results were compared with a commercial enzyme linked immunosorbent assay (ELISA) as gold standard. Quantification of HBsAg was performed in false negative samples. A total of 511 subjects were screened, of whom 81 (15.9 %) were HBsAg-positive with the gold standard. All three POC-RDTs were positive in 65 of the 81 positive samples, yielding a sensitivity (95 % confidence interval) of 80.2 % (70.3-87.5) and a specificity of 99.8 % (98.7-100 for Healgen® and Determine™; 98.6-100 for Advanced Quality™). False negatives were observed in 16 patients associated with low levels of HBsAg (median 1.5 IU/mL). All three POC-RDTs had reasonably high sensitivity and excellent specificity, but false negative results were observed in patients with low titres of HBsAg. Thus, these POC-RDTs might be useful to identify patients in need of HBV treatment, but cannot be recommended as blood donor screening tests.

Dynamic profile of the HBeAg-anti-HBe system in acute and chronic hepatitis B virus infection: A clinical-laboratory approach

Wild-type HBV infection is followed by the blood expression of its widely known serological markers of infection, and designated as, hepatitis B virus surface antigen (HBsAg) and its antibody (anti-HBs), anti-HBc antibodies (IgM/IgG), and hepatitis B virus 'e' antigen (HBeAg) and its antibody (anti-HBe). These markers are detected as the infection develops and its kinetic behavior serves as a basis for monitoring the disorder and for diagnosing the clinical form or infection phase. Among these, the HBeAg-anti-HBe system markers demonstrate a dynamic profile whose interpretation, both in the acute or chronic HBV infection context, can offer greater difficulty to the health professionals, due to its particularities. This review offers a revisit to the markers dynamics of this system in the acute and chronic HBV infection and to the clinical and laboratory significance of its expression in these two clinical contexts.

Upconverting nanoparticle reporter-based highly sensitive rapid lateral flow immunoassay for hepatitis B virus surface antigen

Detection of hepatitis B Virus surface antigen (HBsAg) is an established method for diagnosing both acute and chronic hepatitis B virus (HBV) infection. In addition to enzyme immunoassays (EIAs), rapid diagnostic tests (RDTs) are available for the detection of HBsAg in resource-poor settings. However, the available RDTs have inadequate sensitivity and therefore are not suitable for diagnosis of patients with low levels of HBsAg and for blood screening. To provide a high-sensitivity RDT, we developed a lateral flow immunoassay (LFIA) for HBsAg utilizing upconverting nanoparticle (UCNP) reporter. The UCNP-LFIA can use whole blood, serum, or plasma and the results can be read in 30 min using a reader device. When compared with a commercial conventional visually read LFIA, the developed UCNP-LFIA had a Limit of Detection (LoD) of 0.1 IU HBsAg/ml in spiked serum, whereas the LoD of the conventional LFIA was 3.2 IU HBsAg/ml. The developed UCNP-LFIA fulfills the WHO criterion for blood screening (LoD ≤ 0.13 IU HBsAg/ml) in terms of LoD. The UCNP-LFIA and conventional LFIA were evaluated with well-characterized sample panels. The UCNP-LFIA detected 20/24 HBsAg-positive samples within the HBsAg Performance Panel and 8/10 samples within the Mixed Titer Performance Panel, whereas the conventional LFIA detected 8/24 and 4/10 samples in these panels, respectively. The performance of the assays was further evaluated with HBsAg-positive (n = 108) and HBsAg-negative (n = 315) patient samples. In comparison with a central laboratory test, UCNP-LFIA showed 95.4% (95% CI: 89.5–98.5%) sensitivity whereas sensitivity of the conventional LFIA was 87.7% (95%CI: 79.9–93.3%).

Hepatitis B virus American genotypes: Pathogenic variants ?

Hepatitis B virus (HBV) chronic infection is responsible for almost 900.000 deaths each year, due to cirrhosis or hepatocellular carcinoma (HCC). Ten HBV genotypes have been described (A-J). HBV genotype F and H circulate in America. HBV genotypes have been further classified in subgenotypes. There is a strong correlation between the genetic admixture of the American continent and the frequency of genotypes F or H: a high frequency of these genotypes is found in countries with a population with a higher ratio of Amerindian to African genetic admixture. The frequency of occult HBV infection in Amerindian communities from Latin America seems to be higher than the one found in other HBV-infected groups, but its association with American genotypes is unknown. There is growing evidence that some genotypes might be associated with a faster evolution to HCC. In particular, HBV genotype F has been implicated in a frequent and rapid progression to HCC. However, HBV genotype H has been associated to a less severe progression of disease. This study reviews the diversity and frequency of autochthonous HBV variants in the Americas and evaluates their association to severe progression of disease. Although no significant differences were found in the methylation pattern between different genotypes and subgenotypes of the American types, basal core promoter mutations might be more frequent in some subgenotypes, such as F1b and F2, than in other American subgenotypes or genotype H. F1b and probably F2 may be associated with a severe presentation of liver disease as opposed to a more benign course for subgenotype F4 and genotype H. Thus, preliminary evidence suggests that not all of the American variants are associated with a rapid progression to HCC.

[Rapid diagnosis of sexually transmitted infections : Joint statement of DSTIG, RKI, and PEI, as well as the reference centers for HIV, HBV, and HCV and consulting laboratories for Chlamydia, gonococci, and Treponema pallidum]

In February 2019, the fourth expert meeting on rapid diagnostic tests (RDTs) for sexually transmitted infections (STI) was held at the Robert Koch Institute (RKI) in Berlin. Novel technical developments and new aspects of RDT applications were discussed by representatives from the German STI Society (DSTIG); RKI; the Paul Ehrlich Institute; national reference centers for HIV, HBV, and HCV; and reference laboratories for Chlamydia, gonococci, and Treponema pallidum.As a result of this meeting, we present a revision of the joint statement on STI diagnostics with RDTs from 2017. The Regulation (EU) 2017/746 of the European Parliament and of the Council on in vitro diagnostic medical devices became effective in May 2017 and includes more stringent regulatory requirements for RDTs, mainly concerning conformity of manufacturing processes and performance characteristics of class D in vitro diagnostics (detection of HIV, HBV, HCV, and T. pallidum). Some RDTs for HIV, HCV, and T. pallidum have been evaluated in clinical studies and/or were WHO prequalified and may be used in low-threshold services. Among them are some HIV RDTs available and approved for self-testing. In addition, some HBV RDTs based on detection of HBs antigen (HBsAg) received WHO prequalification. However, false negative results may occur in samples with low HBsAg levels, as for instance in HIV-coinfected patients receiving antiretroviral therapy. For Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG), antigen-based RDTs still do not allow reliable detection of infection. Only PCR-based CT/NG RDTs possess sufficient diagnostic accuracy to be used as point-of-care tests. Rapid PCR tests for NG, however, do not provide any information about antimicrobial resistance.

Point-of-Care Tests for Hepatitis B: An Overview

Despite the heavy disease burden posed by hepatitis B, around 90% of people living with hepatitis B are not diagnosed globally. Many of the affected populations still have limited or no access to essential blood tests for hepatitis B. Compared to conventional blood tests which heavily rely on centralised laboratory facilities, point-of-care testing for hepatitis B has the potential to broaden testing access in low-resource settings and to engage hard-to-reach populations. Few hepatitis B point-of-care tests have been ratified for clinical use by international and regional regulatory bodies, and countries have been slow to adopt point-of-care testing into hepatitis B programs. This review presents currently available point-of-care tests for hepatitis B and their roles in the care cascade, reviewing evidence for testing performance, utility, acceptability, costs and cost-effectiveness when integrated into hepatitis B diagnosis and monitoring programs. We further discuss challenges and future directions in aspects of technology, implementation, and regulation when adopting point-of-care testing in hepatitis B programs.

Evaluation of the analytical performance of six rapid diagnostic tests for the detection of viral hepatitis B and C in Lubumbashi, Democratic Republic of Congo

Rapid diagnostic tests (RDTs) are widely used in Lubumbashi for the diagnosis of viral hepatitis B and C. To date, there are no works that have been carried out in Lubumbashi to independently assess the performance of such tests. This study aimed at assessing the effectiveness of RDTs for the detection of HBsAg and anti-HCV antibodies in order to identify infected blood donors in Lubumbashi. A total of 300 serum samples (100 HBsAg positive samples; 100 anti-HCV positive samples and 100 HBsAg and anti-HCV negative samples) were tested simultaneously using the 6 locally used RDTs and as gold standard the chemiluminescent assays for HBsAg and the RT-TMA for HCV detection. The six evaluated RDTs demonstrated a sensitivity and a negative predictive value (NPV) of 100 % whereas the specificity and positive predictive value (PPV) varied from 46 % to 98.1 %. SB BioLine HBsAg test performed best in this study with 100 % of sensitivity, 97.1 % of specificity, 100 % of NPV and 96.9 % of PPV. Furthermore, sensitivity, specificity, NPV and PPV for SB BioLine HCV test were as follows: 100 %, 98.1 %, 100 % and 93.9 %. Therefore, SD BioLine tests (HBsAg, HCV) would be selected as the first line RDTs for the detection and the diagnostic of hepatitis B and C. They can prevent blood-borne transmission of HBV and HCV in areas with limited incomes as Lubumbashi.

Immunoreactivity pattern of monoclonal antibodies against Hepatitis B vaccine with global Hepatitis B virus genotypes

Hepatitis B surface antigen (HBsAg) specific monoclonal antibodies (mAbs) are potentially valuable therapeutic and diagnostic tool. We have previously established and characterized a panel of mAbs derived from immunized BALB/c mice with a yeast-derived recombinant HB vaccine subgentoype A2 and HBsAg subtype adw2. This study was conducted to evaluate the reactivity pattern of this anti-HBs mAbs panel with various genotypes and subgenotypes of HBV using the first WHO HBV genotype reference panel containing 15 serum samples representing the subgenotypes A1, A2, B1, B2, C2, D1-D3, E, F2, and H. Ten out of 21 anti-HBs mAbs were able to strongly recognize all gentopye/subtypes of HBsAg provided in the WHO reference panel. However, 10 out of 21 anti-HBs mAbs showed a moderate to profound loss of reactivity with HBV genotypes/HBsAg subtypes D2/ayw3, E/ayw4, F2/adw4, and H/adw4. Two mAbs from the second group displayed a profoundly reduced reactivity with only 1 out of 3 C2/adr genotype/subtype samples. The amino acid alignment of these 3 samples showed that this particular sample contains amino acid substitution at residue 127, which is located inside "a" determinant. This amino acid substitution, which profoundly affected the reactivity of anti-HBs antibodies, has been previously reported only in D/ayw3, E/ayw4, F/adw4, and H. Interestingly, the amino acid alignment of the samples in this WHO panel showed that P127T substitution can also be found in C2/adr. Comparing amino acids sequences inside the antigenic loop (AGL) showed that D2/ayw3 contains a T118A/P127T double substitution, E/ayw4 contains P127L/T140S, F2/adw4 contains P127L/T140S/ F158L, and H/adw4 contains P127L substitution. Therefore, amino acid variability at positions 118, 127, 140, and 158 was found to cause significant loss of reactivity with anti-HBs mAbs. Since HBsAg variability in different genotypes of HBV can profoundly affect the reactivity of anti-HBs mAbs, analytical sensitivity for HBsAg assays should be considered based on the circulating and common HBV variants in the relevant countries.

Evaluation of Four Rapid Tests for Detection of Hepatitis B Surface Antigen in Ivory Coast

Background

Hepatitis B virus (HBV) infection is a leading cause of liver disease worldwide. Hepatitis B surface antigen (HBsAg) rapid diagnostic tests (RDTs) could be an ideal tool for a large-scale HBV screening in settings with high endemicity but limited infrastructure. The aim of this study was to evaluate the diagnosis performance of such RDTs for screening HBV infection in Ivory Coast.

Methods

From September 2018 to January 2019, a cross-sectional phase I evaluation study of RDTs was conducted in three laboratories of Abidjan (CeDReS, CNTS and IPCI), on a panel of 405 whole blood samples and 699 plasmas. Four HBsAg RDTs (Determine™ HBsAg, SD Bioline HBsAg WB®, Standard Q HBsAg® and Vikia HBsAg®) were evaluated. The diagnostic performance (sensitivity and specificity) was calculated in comparison to the reference sequential algorithms of two EIA tests (Dia.Pro HBsAg® one version ULTRA and Monolisa™ HBsAg ULTRA).

Results

The Determine™ HBsAg and Vikia HBsAg® tests performed well, with 100% of sensitivity, specificity both on plasma and on whole blood. For SD Bioline HBsAg WB® and Standard Q HBsAg®, the specificities were 99.8% and the sensitivities 99.3% and 97.1% respectively. Finally, there were a total of 19 false negative results: 3 with SD Bioline HBsAg WB® and 16 with Standard Q HBsAg®.

Conclusion

Determine HBsAg® from Alere and Vikia HBsAg® from Biomérieux are the most suitable RDTs for screening for HBV in Ivory Coast. A phase II evaluation must be initiated.

The contribution of more sensitive hepatitis B surface antigen assays to detecting and monitoring hepatitis B infection

BACKGROUND

Hepatitis B surface antigen (HBsAg) remains the main viral marker for screening and monitoring hepatitis B virus (HBV) infection. The quantification limit of most current HBsAg assays is around 0.05 IU/mL. The Lumipulse-G-HBsAg-Quant assay (Fujirebio) claims to obtain a tenfold improvement in sensitivity. This study aimed to assess the performance of this assay in detecting low HBsAg levels in clinical samples.

METHODS

Three panels of stored frozen samples were selected on the basis of HBV-DNA and HBsAg values obtained previously with routine techniques. Panels 1 (n=13) and 2 (n=52) consisted of DNA-positive/HBsAg-negative samples from individuals in the window period and with occult HBV infection respectively. Panel 3 comprised 23 samples with low or discrepant HBsAg screening results. All these samples were tested retrospectively with the DiaSorin and Fujirebio HBsAg assays.

RESULTS

Sixteen out of 65 samples (25 %), initially screened HBsAg negative, were reactive only with the Fujirebio assay (median value= 0.015 IU/mL; IQR= 0.012): three (23 %) samples from panel 1 and 13 (25 %) from panel 2. Thirteen of these 16 (81 %) had HBsAg values below 0.03 IU/mL with the DiaSorin assay. In panel 3, 22 (96 %) samples were quantified successfully with the Fujirebio assay (median: 0.32 IU/mL; IQR: 1.20) and 19 (83 %) with the DiaSorin assay (median: 0.31 IU/mL; IQR: 0.65). Concentrations obtained with the two assays showed good correlations (r=0.893, Spearman).

CONCLUSIONS

HBsAg assays with enhanced analytical sensitivity could improve HBV serological profile interpretation with possible consequences on clinical management of infected patients, and on blood transfusion safety.

Dried Blood Spot Tests for the Diagnosis and Therapeutic Monitoring of HIV and Viral Hepatitis B and C

Blood collected and dried on a paper card – dried blood spot (DBS) – knows a growing interest as a sampling method that can be performed outside care facilities by capillary puncture, and transported in a simple and safe manner by mail. The benefits of this method for blood collection and transport has recently led the World Health Organization to recommend DBS for HIV and hepatitis B and C diagnosis. The clinical utility of DBS sampling to improve diagnostics and care of HIV and hepatitis B and C infection in hard to reach populations, key populations and people living in low-income settings was highlighted. Literature about usefulness of DBS specimens in the therapeutic cascade of care – screening, confirmation, quantification of nucleic acids, and resistance genotyping -, was reviewed. DBS samples are suitable for testing antibodies, antigens, or nucleic acids using most laboratory methods. Good sensibility and specificity have been reported for infant HIV diagnosis and diagnosis of hepatitis B and C. The performance of HIV RNA testing on DBS to identified virological failure on antiretroviral therapy is also high but not optimal because of the dilution of dried blood in the elution buffer, reducing the analytical sensitivity, and because of the contamination by intracellular HIV DNA. Standardized protocols are needed for inter-laboratory comparisons, and manufacturers should pursue regulatory approval for in vitro diagnostics using DBS specimens. Despite these limitations, DBS sampling is a clinically relevant tool to improve access to infectious disease diagnosis worldwide.

Impact of hepatitis B virus genotype F on in vitro diagnosis: detection efficiency of HBsAg from Amerindian subgenotypes F1b and F4

The influence of the high genetic variability of hepatitis B virus (HBV) on the sensitivity of serological assays has received little attention so far. A major source of variability is related to viral genotypes and subgenotypes. Their possible influence on diagnosis and prophylaxis is poorly known and has mostly been evaluated for genotypes A, B, C and D. Robust data showing the detection efficiency of HBsAg from genotype F is lacking. This study examined the effect of virus-like particles containing HBsAg from genotypes A and F (particularly, F1b and F4) produced in Pichia pastoris in relation to the anti-HBs antibodies used in the immunoassays for in vitro diagnosis and compared it with that exerted by the G145R S-escape mutant. The results showed that HBsAg detection rates for subgenotypes F1b and F4 differed significantly from those obtained for genotype A and that subgenotype F1b had a major impact on the sensitivity of the immunoassays tested. Prediction of the tertiary structure of subgenotypes F1b and F4 revealed changes inside and outside the major hydrophilic region (aa 101-160) of the HBsAg compared to genotype A and the G145R variant. A phosphorylation site (target for protein kinase C) produced by the G145R substitution might prevent recognition by anti-HBs antibodies. In conclusion, the use of different genotypes or variants for diagnosis could improve the rate of detection of HBV infection. The incorporation of a genotype-F-derived HBsAg vaccine in areas where this genotype is endemic should be evaluated, since this might also affect vaccination efficacy.

Antiviral drug resistance and hepatitis B: a continuing public health problem

The use of selective antiviral therapy has been very successful in controlling HBV replication in individuals, leading to a reduction in disease progression and mortality. However, the use of first-generation therapies, often the only available option in low-resource settings, can result in a high prevalence of drug resistance mutations. Variants selected by antiviral therapies targeting the viral polymerase can also result in variants in the viral envelope. These variants can allow the virus to escape the host immune response. The effect of antiviral selection pressure on viral variants that may contribute to immune escape requires further investigation.

Analytical performance of newly developed rapid point-of-care test for the simultaneous detection of hepatitis A, B, and C viruses in serum samples

ABSTRACTBACKGROUND

Although immunoassays play a major role in the detection of hepatitis viruses, there is a need for a point-of-care (POC) test. We evaluated the EuDx-HE (A,B,C) kit (EUDIPIA, Cheongju, Korea), which detects anti-hepatitis A virus (HAV) immunoglobulin M (IgM), hepatitis B virus surface antigen (HBsAg), and anti-hepatitis C virus (HCV) immunoglobulin G (IgG) simultaneously using an immunochromatographic method within 15 minutes.

METHODS

A total of 1581 serum samples including 57, 477, and 451 samples positive for anti-HAV IgM, HBsAg, and anti-HBV IgG, respectively, were analyzed. We investigated the diagnostic accuracy of the EuDx-HE (A,B,C) kit by comparison with SD BIOLINE POC kits (Abbott, Chicago, IL) using Architect immunoassays as a reference method.

RESULTS

For anti-HAV IgM and HBsAg detection, the EuDx-HE (A,B,C) kit showed a higher sensitivity and a slightly lower specificity than the SD BIOLINE kit. For anti-HCV IgG detection, the EuDx-HE (A,B,C) kit had a higher sensitivity and a higher specificity than the SD BIOLINE kit. The agreement for positivity between the POC tests was >89.47%, with κ values of 0.844, 0.941, and 0.943 for HAV, HBV, and HCV, respectively.

CONCLUSION

The EuDx-HE (A,B,C) kit showed an acceptable clinical performance for detecting anti-HAV IgM, HBsAg, and anti-HCV.

New and Old Biomarkers for Diagnosis and Management of Chronic Hepatitis B Virus Infection

Tests to detect the presence and activity of hepatitis B virus (HBV) are the cornerstones of diagnosis and management. Assays that detect or measure serum levels of HB surface antigen, HB surface antibody, and HB core antibody are used to identify patients with exposure to HBV, whereas other tests provide information on the level of virus replication, presence of specific variants, and presence of virus reservoirs. Newer diagnostic tests, used only in research settings so far, aim to quantify levels of intrahepatic HBV replication. Other tests have been developed to detect HBV infection in resource-limited settings. We review point-of-care tests (essential in global screening efforts), standard diagnostic tests used in routine clinical management, and newer tests that might be used in clinical trials of agents designed to cure HBV infection.

Evaluation of reliability and performance of hepatitis B virus-e-antigen assays in tertiary care setting

Hepatitis B virus-e-antigen (HBeAg) is a viral marker to assess hepatitis B virus (HBV) replication. We have evaluated the reliability of three commonly available HBeAg immunoassays using World Health Organization-International Standard and clinical samples. In addition the performance of enzyme immunoassays (EIAs) was assessed by kinetic binding and reagent exchange experiments. Analytical and diagnostic sensitivity were significantly different among HBeAg assays (P < 0.01). The affinity of capture/detector antibodies varied significantly between EIAs (P < 0.01). Our findings suggest that significant difference in the affinity of capture/detector antibodies to HBeAg may impact the overall performance and the reliability of currently available HBeAg assays in HBV diagnosis and management.

Development of a Rapid Automated Fluorescent Lateral Flow Immunoassay to Detect Hepatitis B Surface Antigen (HBsAg), Antibody to HBsAg, and Antibody to Hepatitis C

Background

Accurate, rapid, and cost-effective screening tests for hepatitis B virus (HBV) and hepatitis C virus (HCV) infection may be useful in laboratories that cannot afford automated chemiluminescent immunoassays (CLIAs). We evaluated the diagnostic performance of a novel rapid automated fluorescent lateral flow immunoassay (LFIA).

Methods

A fluorescent LFIA using a small bench-top fluorescence reader, Automated Fluorescent Immunoassay System (AFIAS; Boditech Med Inc., Chuncheon, Korea), was developed for qualitative detection of hepatitis B surface antigen (HBsAg), antibody to HBsAg (anti-HBs), and antibody to HCV (anti-HCV) within 20 minutes. We compared the diagnostic performance of AFIAS with that of automated CLIAs—Elecsys (Roche Diagnostics GmbH, Penzberg, Germany) and ARCHITECT (Abbott Laboratories, Abbott Park, IL, USA)—using 20 seroconversion panels and 3,500 clinical serum samples.

Results

Evaluation with the seroconversion panels demonstrated that AFIAS had adequate sensitivity for HBsAg and anti-HCV detection. From the clinical samples, AFIAS sensitivity and specificity were 99.8% and 99.3% for the HBsAg test, 100.0% and 100.0% for the anti-HBs test, and 98.8% and 99.1% for the anti-HCV test, respectively. Its agreement rates with the Elecsys HBsAg, anti-HBs, and anti-HCV detection assays were 99.4%, 100.0%, and 99.0%, respectively. AFIAS detected all samples with HBsAg genotypes A-F and H and anti-HCV genotypes 1, 1a, 1b, 2a, 2b, 4, and 6. Cross-reactivity with other infections was not observed.

Conclusions

The AFIAS HBsAg, anti-HBs, and anti-HCV tests demonstrated diagnostic performance equivalent to current automated CLIAs. AFIAS could be used for a large-scale HBV or HCV screening in low-resource laboratories or low-to middle-income areas.

Diabetes, Plasma Glucose, and Incidence of Fatty Liver, Cirrhosis, and Liver Cancer: A Prospective Study of 0.5 Million People

The prevalence of diabetes is increasing rapidly in China. However, evidence is limited about its effects on chronic liver diseases and liver cancer. We examined the associations of diabetes with chronic liver diseases and liver cancer and of random plasma glucose (RPG) with these liver diseases among participants without diabetes in Chinese adults and the possible interaction by hepatitis B virus (HBV) infection. The prospective China Kadoorie Biobank recruited 512,891 adults. During 10 years of follow-up, 2,568 liver cancer, 2,082 cirrhosis, 1,298 hospitalized nonalcoholic fatty liver disease (NAFLD), and 244 hospitalized alcoholic liver disease (ALD) cases were recorded among 503,993 participants without prior history of cancer or chronic liver diseases at baseline. Cox regression was used to estimate hazard ratios (HRs) for each disease by diabetes status (previously diagnosed or screen-detected) and, among those without previously diagnosed diabetes, by levels of RPG. Overall 5.8% of participants had diabetes at baseline. Compared to those without diabetes, individuals with diabetes had adjusted HRs of 1.49 (95% confidence interval 1.30-1.70) for liver cancer, 1.81 (1.57-2.09) for cirrhosis, 1.76 (1.47-2.16) for NAFLD, and 2.24 (1.42-3.54) for ALD. The excess risks decreased but remained elevated in those with longer duration. Among those without previously diagnosed diabetes, RPG was positively associated with liver diseases, with adjusted HRs per 1 mmol/L higher RPG of 1.04 (1.03-1.06) for liver cancer, 1.07 (1.05-1.09) for cirrhosis, 1.07 (1.05-1.10) for NAFLD, and 1.10 (1.05-1.15) for ALD. These associations did not differ by HBV infection.

CONCLUSION

In Chinese adults, diabetes and higher blood glucose levels among those without known diabetes are associated with higher risks of liver cancer and major chronic liver diseases.

Peer-to-Peer Sessions in Primary Care to Improve the Hepatitis B Detection Rate in Seville, Spain

INTRODUCTION AND AIM

The detection of hepatitis B virus (HBV) depends on primary care center activity. The present study aims to investigate the impact of peer-to-peer sessions with hepatologists on hepatitis B screening efficacy in primary care centers.

MATERIAL AND METHODS

Peer-to-peer one-hour sessions were scheduled to improve the screening program for HBV in Seville, Spain. The sessions were focused on who should be tested for HBV and how positive cases should be referred. Fourteen out of 26 health care centers were selected to participate in peer-to-peer sessions. The centers were classified according to how many sessions they held (no sessions, one session or more than one session).

RESULTS

Over a five-year period, HBV screening was performed in 32 203 people. In Seville, the prevalence of HBsAg was 0.87% (283/32 203). The detection rates for new HBsAg-positive cases were 7.1, 16.9 and 21.3 cases/105 population/year in non-session, one-time session and more than one session centers, respectively (p < 0.05). The rate of patients who effectively visited centers as outpatients was significantly higher after peer-to-peer sessions-86/94 (91%) for one session and 81/89 (91%) for two session centers vs. 16/27 (67%) for non-session centers (p = 0.002). The only independent predictor of patient referral was peer-to-peer sessions (OR, 1.925 [95% CI, 1.002-3.699]; p < 0.05).

CONCLUSIONS

Peer-to-peer sessions in primary care centers increased HBV detection and visitation rates.

Evaluation of performance testing of different rapid diagnostic kits in comparison with EIAs to validate detection of hepatitis B virus among high risk group in Nigeria

BACKGROUND

Hepatitis B virus (HBV) causes chronic liver-associated diseases and its early detection is of high public health importance. Its diagnosis is mainly based on immunological assays among which Enzyme-Linked Immunosorbent Assay (ELISA) and rapid tests are the most common and widespread methods. However, a major challenge is the discordance of results of any two laboratory assays which cannot be easily resolved. Therefore, this study was designed to evaluate the validity and reliability of commercially available five rapid test kits in comparison with two Enzyme Immunoassays (EIAs) in Nigeria using hepatitis B surface antigen as a reference marker.

METHODS

A total of 100 sera of previously diagnosed consenting HBV-positive patients from private diagnostic laboratories in Ibadan between March and August, 2011 were tested using two EIA and five rapid commercially available HBV test kits in Nigeria. Data were analyzed by SPSS version 15, while bivariate and multivariate analyses were carried out to identify associations at P < 0.05 considered significant.

RESULTS

Overall, the sensitivity rates of the two EIA kits were 100% and 99.9% (95% confidence interval [CI] = 98.9-99.7) with specificity of 100% and 99.9% (95% CI = 98.9-99.7), respectively. The sensitivity of the five rapid test kits ranged from 97.5% (95% CI = 96.4-97.6) to 98.9% (95% CI = 97.9-99.9) with specificity of 80% (95% CI = 79.3-80.9) to 90% (95% CI = 89.2-91.0). Also, the positive predictive value ranged from 88% (95% CI = 88.2-89.9) to 89% (95% CI = 88.2-89.9), while the negative predictive value ranged from 80% (95% CI = 79.3-80.9) to 90% (95% CI = 89.2-91.0) for the five rapid kits. However, that of the two EIAs ranged from 99.9% (98.9-99.7) to 100%. Further analysis showed significant (P = 0.033) variations in the sensitivity and specificity of the EIAs and rapid test kits.

CONCLUSIONS

The results from this study have clearly revealed the challenges of diagnosis of HBV infections in Nigeria. This study has also demonstrated that the sensitivity of most of the rapid test kits may not be adequate when compared with EIA for early detection of HBV infections. The implications of possible misdiagnosis on the various intervention strategies that rely predominantly on correct HBV status of an individual are enormous. Therefore, there is the need to further compliment the use of rapid test kits with EIAs for HBV control in Nigeria.

Twenty-Year Evolution of Hepatitis B Virus and Human Immunodeficiency Virus Prevalence and Incidence in Voluntary Blood Donors in Côte d'Ivoire

Background

Hepatitis B virus (HBV) and human immunodeficiency virus (HIV) share common risk factors. The parallel description of their frequency over time may help capture their similarities and differences.

Methods

Using data from the National Transfusion Center of Abidjan, we estimated the following over a 20-year period: (1) the prevalence of HIV and hepatitis B surface antigen (HBsAg) positivity at first contact; and (2) the incidence of HIV and HBsAg seroconversion in negative first-time blood donors.

Results

Between 1992 and 2012, 422319 donors (men [M] = 74%) provided 1063825 blood donations. For first-time donors, HIV prevalence decreased from 7.1% (M = 5.9%, women [W] =11.0%) in 1992-1994 to 1.1% (M = 0.8%, W = 2.0%) in 2010-2012. Prevalence of HBsAg positivity remained stable at 10.8% (M = 11.7%, W = 7.3%) in 1992-1994 to 11.1% (M = 12.5%, W = 7.1%) in 2010-2012. Among regular donors (N = 129256), the incidence of becoming HIV or HBsAg positive, respectively, decreased from 4.9 per 100 (M = 4.5, W = 8.6) and 7.3 per 100 person-years (M = 7.8, W = 2.3) in 1992-1994 to 0.07 (M = 0.06, W = 0.11) and 0.2 per 100 person-years (M = 0.2, W = 0.2) in 2010-2012.

Conclusions

Human immunodeficiency virus prevalence and incidence decreased dramatically over time, whereas HBV prevalence remained stable. Incidence of HBsAg seroconversion, although decreasing, still reached unexpected levels, suggesting that the risk of HBV infection in adults may be higher than expected. Hepatitis B surface antigen-negative blood-donors should be offered HBV vaccination.

Hepatitis B Virus Blood Screening: Need for Reappraisal of Blood Safety Measures?

Over the past decades, the risk of HBV transfusion–transmission has been steadily reduced through the recruitment of volunteer donors, the selection of donors based on risk-behavior evaluation, the development of increasingly more sensitive hepatitis B antigen (HBsAg) assays, the use of hepatitis B core antibody (anti-HBc) screening in some low-endemic countries, and the recent implementation of HBV nucleic acid testing (NAT). Despite this accumulation of blood safety measures, the desirable zero risk goal has yet to be achieved. The residual risk of HBV transfusion–transmission appears associated with the preseroconversion window period and occult HBV infection characterized by the absence of detectable HBsAg and extremely low levels of HBV DNA. Infected donations tested false-negative with serology and/or NAT still persist and derived blood components were shown to transmit the virus, although rarely. Questions regarding the apparent redundancy of some safety measures prompted debates on how to reduce the cost of HBV blood screening. In particular, accumulating data strongly suggests that HBsAg testing may add little, if any HBV risk reduction value when HBV NAT and anti-HBc screening also apply. Absence or minimal acceptable infectious risk needs to be assessed before considering discontinuing HBsAg. Nevertheless, HBsAg remains essential in high-endemic settings where anti-HBc testing cannot be implemented without compromising blood availability. HBV screening strategy should be decided according to local epidemiology, estimate of the infectious risk, and resources.

Seroprevalence of hepatitis B surface antigen (HBsAg) in Bo, Sierra Leone, 2012-2013

OBJECTIVE

The aim of this study was to determine the prevalence of hepatitis B surface antigen (HBsAg) among febrile individuals tested at Mercy Hospital Research Laboratory (MHRL) in Bo, Sierra Leone.

RESULTS

A total of 860 febrile individuals ages 5 years and older were tested by MHRL between July 2012 and June 2013 with a Standard Diagnostics Bioline HBsAg rapid diagnostic test. The overall HBsAg prevalence rate was 13.7%, including a rate of 15.5% among males and 12.6% among females. The HBsAg rate did not differ by child or adult age group (p > 0.5). The prevalence rate in Bo was similar to the 11-15% HBsAg prevalence rates reported in the past decade from other studies across West Africa. Scaling up the infant hepatitis B vaccination program in Sierra Leone will be important for reducing the future burden of disease and premature death attributable to chronic viral hepatitis B disease.

How to improve access to therapy in hepatitis B patients

Despite the availability of a preventive vaccine and active antiviral treatments that stop disease progression and reduce the risk of hepatocellular carcinoma, hepatitis B is still a major public health problem. Only an estimated 10% of the 257 million people living with HBV have been diagnosed and as few as 1% are being adequately treated. Barriers to diagnosis and treatment include: (i) limited awareness and lack of knowledge about HBV infection and HBV-related diseases; (ii) under-diagnosis with insufficient screening and referral to care; (iii) limited treatment due to drug availability, costs, reimbursement policies and the need for long-term or life-long therapy. These barriers and the actions needed to improve access to treatment are strongly influenced by the prevalence of infection and affect middle-high vs low-middle income countries differently, where most HBV carriers are found. In high-prevalence regions and low-to middle-income countries, the main challenges are availability and cost while in low-prevalence regions and middle-to high-income countries low screening rates, public awareness, social stigma and discrimination play an important role. Overcoming these challenges on a global scale is a complex clinical and public health challenge and multilateral commitment from pharmaceutical companies, governments, funders and the research community is lacking. The new WHO 2016 Global Health Sector Strategy on viral hepatitis targets testing and treatment, suggesting that important but strong actions are needed from advocacy groups, scientific societies and funding agencies to foster awareness and access to cure.

Hepatitis B infection among HIV infected individuals in Gabon: Occult hepatitis B enhances HBV DNA prevalence

In Gabon, a central African country, human immunodeficiency virus (HIV) and hepatitis B virus (HBV) are endemic. In a recent study, conducted in a semi-urban area (Franceville, Gabon), HBV infection was found to be more prevalent among HIV infected individuals. This study aims to investigate the prevalence and genetic diversity of hepatitis B virus infection among HIV infected individuals, predominantly under antiretroviral therapy, living in fully urbanized area: Libreville, capital of Gabon. Serological and molecular tests were performed to detect HBV infection among patients living with HIV/AIDS (PLHA). We used Monolisa HBsAg ULTRA, Anti-HBc Plus and Anti-HBs Plus EIA kits for serological analyses. HBV DNA viral load (HBV DNA VL) was determined by real time PCR and molecular characterization of HBV strains was performed by sequencing and phylogenetic analysis of partial HBV surface and core genes. At all, 70.2% of patients were under antiretroviral therapy. The prevalence of HBsAg was 8.8% (43/487). Detectable HBV DNA was found in 69.7% (30/43) of HBsAg positive patients and in 17.5% (24/137) HBsAg negative patients. HBV DNA VL was significantly higher among patient with CD4 cell counts less than 200 cells/mm³ than those with CD4 cell counts greater than 500 cells/mm³ (p = 0.008). We confirmed the presence of HBV sub-genotypes QS-A3 (40%), and A4 (20%) and HBV-E genotype (40%). The percentage of resistance to Lamivudine was high (40%) and varied according to the M204V/I motif. Occult hepatitis B infection (OBI) was found in patients with isolated HBcAb and among patients who had completed their HBsAg seroconversion. We detected HBV DNA for one patient without any HBV serological marker. This study provides a new landmark for the comprehension of HBV infection in PLHA in urban areas. OBI enhances HBV DNA prevalence and should be investigated in all HBsAg negative individuals.

Field performance of the Determine HBsAg point-of-care test for diagnosis of hepatitis B virus co-infection among HIV patients in Zambia

BACKGROUND

We evaluated the field performance of a rapid point-of-care (POC) test for hepatitis B surface antigen (HBsAg) that could support decentralization and scale-up of hepatitis B virus (HBV) diagnosis in Africa.

OBJECTIVE

To determine the field performance of the Determine HBsAg POC test for diagnosis of HBV co-infection among HIV patients in Zambia.

STUDY DESIGN

Between 2013-2014, we screened HIV-infected adults for HBsAg at two urban clinics in Zambia. A subset were tested with the POC Determine HBsAg (Alere, USA) by finger prick in the clinic and HBsAg serology (Access2Analyzer, Beckman Coulter) at a reference laboratory. If either test was reactive, we determined HBV viral load (VL) and genotype. We described patient demographic and clinical characteristics (including liver fibrosis) and assessed the sensitivity, specificity, positive and negative predictive values (PPV and NPV) of the Determine test. In secondary analyses, we assessed sensitivity among patients with replicating HBV (i.e., VL>20 IU/ml) and with high HBV VL (i.e.,>20,000IU/ml).

RESULTS

Among 412 participants with both HBsAg tests, median age was 34 years, 51% were women, and median CD4 was 208 cells/mm³. By serology, 66 (16%) were HBsAg-positive. Overall Determine had 87.9% sensitivity, 99.7% specificity, 98.3% PPV, and 97.7% NPV. Six of 8 patients with false negative results had undetectable HBV VL and no evidence of significant liver fibrosis. Test sensitivity was 95.9% among the 51 with replicating HBV and 100% among the 28 with high HBV VL.

CONCLUSIONS

Determine HBsAg is a cheaper alternative HBV testing option compared to the gold standard ELISA and has high specificity and good sensitivity in the field among HIV-infected individuals.

Diagnostic accuracy of tests to detect hepatitis B surface antigen: a systematic review of the literature and meta-analysis

BACKGROUND

Chronic Hepatitis B Virus (HBV) infection is characterised by the persistence of hepatitis B surface antigen (HBsAg). Expanding HBV diagnosis and treatment programmes into low resource settings will require high quality but inexpensive rapid diagnostic tests (RDTs) in addition to laboratory-based enzyme immunoassays (EIAs) to detect HBsAg. The purpose of this review is to assess the clinical accuracy of available diagnostic tests to detect HBsAg to inform recommendations on testing strategies in 2017 WHO hepatitis testing guidelines.

METHODS

The systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines using 9 databases. Two reviewers independently extracted data according to a pre-specified plan and evaluated study quality. Meta-analysis was performed. HBsAg diagnostic accuracy of rapid diagnostic tests (RDTs) was compared to enzyme immunoassay (EIA) and nucleic-acid test (NAT) reference standards. Subanalyses were performed to determine accuracy among brands, HIV-status and specimen type.

RESULTS

Of the 40 studies that met the inclusion criteria, 33 compared RDTs and/or EIAs against EIAs and 7 against NATs as reference standards. Thirty studies assessed diagnostic accuracy of 33 brands of RDTs in 23,716 individuals from 23 countries using EIA as the reference standard. The pooled sensitivity and specificity were 90.0% (95% CI: 89.1, 90.8) and 99.5% (95% CI: 99.4, 99.5) respectively, but accuracy varied widely among brands. Accuracy did not differ significantly whether serum, plasma, venous or capillary whole blood was used. Pooled sensitivity of RDTs in 5 studies of HIV-positive persons was lower at 72.3% (95% CI: 67.9, 76.4) compared to that in HIV-negative persons, but specificity remained high. Five studies evaluated 8 EIAs against a chemiluminescence immunoassay reference standard with a pooled sensitivity and specificity of 88.9% (95% CI: 87.0, 90.6) and 98.4% (95% CI: 97.8, 98.8), respectively. Accuracy of both RDTs and EIAs using a NAT reference were generally lower, especially amongst HIV-positive cohorts.

CONCLUSIONS

HBsAg RDTs have good sensitivity and excellent specificity compared to laboratory immunoassays as a reference standard. Sensitivity of HBsAg RDTs may be lower in HIV infected individuals.

The serological markers of acute infection with hepatitis A, B, C, D, E and G viruses revisited

Viral hepatitis is a liver infection caused by one of the six hepatitis viruses: hepatitis A, B, C, D, E, and G virus (HAV to HEV and HGV). These agents differ in their biological, immunological, pathological and epidemiological characteristics. They cause infections that, when symptomatic, lead to clinical manifestations and laboratory findings that are not specific to a particular virus, often making differential diagnosis difficult, especially when no knowledge is available regarding the patient's medical history or the epidemiological background. A number of acute-phase serological markers, such as anti-HAV, anti-HBc, anti-HDV and anti-HEV IgM antibodies, are able to provide a clear indication of an infection caused by HAV, HBV, HDV or HEV. Anti-HCV antibodies and HGV/RNA are used for the diagnosis of HCV and HGV infections. The importance of each of these markers will be reviewed, and different factors that can interfere with the diagnosis of acute infections caused by these viruses will be described.

Strategies for the prevention of perinatal hepatitis B transmission in a marginalized population on the Thailand-Myanmar border: a cost-effectiveness analysis

Background

Data on the cost effectiveness of hepatitis B virus (HBV) screening and vaccination strategies for prevention of vertical transmission of HBV in resource limited settings is sparse.

Methods

A decision tree model of HBV prevention strategies utilised data from a cohort of 7071 pregnant women on the Thailand-Myanmar border using a provider perspective. All options included universal HBV vaccination for newborns in three strategies: (1) universal vaccination alone; (2) universal vaccination with screening of women during antenatal visits with rapid diagnostic test (RDT) plus HBV immune globulin (HBIG) administration to newborns of HBV surface antigen positive women; and (3) universal vaccination with screening of women during antenatal visits plus HBIG administration to newborns of women testing HBV e antigen positive by confirmatory test. At the time of the study, the HBIG after confirmatory test strategy was used. The costs in United States Dollars (US$), infections averted and incremental cost effectiveness ratios (ICERs) were calculated and sensitivity analyses were conducted. A willingness to pay threshold of US$1200 was used.

Results

The universal HBV vaccination was the least costly option at US$4.33 per woman attending the clinic. The HBIG after (RDT) strategy had an ICER of US$716.78 per infection averted. The HBIG after confirmatory test strategy was not cost-effective due to extended dominance. The one-way sensitivity analysis showed that while the transmission parameters and cost of HBIG had the biggest impact on outcomes, the HBIG after confirmatory test only became a cost-effective option when a low test cost was used or a high HBIG cost was used. The probabilistic sensitivity analysis showed that HBIG after RDT had an 87% likelihood of being cost-effective as compared to vaccination only at a willingness to pay threshold of US$1200.

Conclusions

HBIG following confirmatory test is not a cost-effective strategy for preventing vertical transmission of HBV in the Thailand-Myanmar border population. By switching to HBIG following rapid diagnostic test, perinatal infections will be reduced by nearly one third. This strategy may be applicable to similar settings for marginalized populations where the confirmatory test is not logistically possible.

Electronic supplementary material

The online version of this article (doi:10.1186/s12879-017-2660-x) contains supplementary material, which is available to authorized users.

Performance of rapid diagnostic tests for detection of Hepatitis B and C markers in HIV infected patients

There is little information describing the influence of HIV infection upon the performance of rapid diagnostic tests (RDTs) for hepatitis B and C virus diagnosis. This study aims to evaluate the performance of RDTs for HBsAg and anti-HCV detection among HIV-infected individuals. A total of 362 HIV infected individuals were recruited from clinics between January 2013 to November 2014 in the southeast and northeast of Brazil. HBsAg and anti-HCV were detected using commercial EIAs and four RDTs: HBV (Vikia HBsAg^® and Wama Imuno-Rapido HBV^®) and HCV (Bioeasy Teste Rápido HCV^® and Wama Imuno-Rapido HCV^®). Reactive HBsAg and anti-HCV serum samples were tested for HBV DNA and HCV RNA. Sensitivity, specificity and kappa statistic were determined. Using EIA, HBsAg and anti-HCV were detected in 14 (3.9%) and 37 (10.2%) serum samples respectively. Using serum only, HBsAg RDTs demonstrated sensitivities and specificities above 92.0% and Kappa values above 89.0%. Anti-HCV RDTs demonstrated sensitivity and specificities above 82.0% and Kappa higher than 89.0%. Using whole blood samples, Vikia HBsAg^® and Wama Imuno-Rapido HCV^® showed sensitivity and specificity above 99.0% with Kappa of 66.4% and 100%, respectively. HIV viral load was higher among discordant results for anti-HCV RDT. RDTs demonstrated good performance in HIV infected individuals showing the usefulness of assays in this population.

Prevalence of Hepatitis B Virus Infection among Pregnant Women Attending Antenatal Clinics in Vientiane, Laos, 2008-2014

The Lao People's Democratic Republic (PDR) is still considered a highly endemic country for hepatitis B, mainly due to perinatal transmission of hepatitis B virus (HBV), despite efforts made since 2004 for universal immunization of newborns. The prevalence of HBV surface antigen (HBsAg) carriage in pregnant women is a relevant marker for the risk of mother-to-child HBV transmission. This study aimed to assess the changes in prevalence of HBV infection among pregnant women attending the Mahosot Prenatal Clinic (Vientiane Capital). Methods. A retrospective study was performed in the Mahosot Hospital Laboratory to collect and analyze all the results of HBsAg testing in pregnant women from 2008 to 2014. Results. Of a total of 13,238 tested women of mean age of 26 years, 720 women (5,44% [95 CI: 5.1–5.8%]) were found HBsAg positive, the annual prevalence ranging from 4.6% to 6.2%. A slight but steady and significant decrease in prevalence over the 7 years of the study could be documented. Conclusion. Although below the 8% hyperendemic threshold, the HBsAg prevalence observed in pregnant women in Vientiane reflects a high risk of HBV perinatal transmission and call for a widespread infant immunization with an HBV vaccine birth dose.

Rapid diagnosis in serology

Serological diagnosis of acute phase infections implies the detection of IgM specific response, an effective marker of primary infection, but with less clinical significance in reactivations or reinfections. The aim of this article is to provide an updated view of the rapid diagnosis in serology by detecting the IgM isotype and reviewing its applications and limitations. Point-of-care (PoC) tests are analyzed. PoC tests are used in geographical areas where traditional tests are not available, as well as in other circumstances where their use brings the diagnosis directly to the target population. Likewise, their use reduces the response time between taking the sample and the diagnosis, making it easier to make clinical decisions. PoC assays have proven cost-effective, especially in preventing vertical transmission of syphilis and HIV infection.

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.

Occult Hepatitis B Virus Infections (Often with Human Herpesvirus 7 Co-Infection) Detected in Pityriasis rosea Patients: A Pilot Study

Background

The etiopathogenesis of Pityriasis rosea (PR), a papulo-squamous skin disease, remains elusive and hypothesized to be caused primarily by human herpesvirus (HHV) 6 or 7 or immune dysfunction.

Aims

The recent increasing incidences of hepatitis B virus (HBV) infections, including asymptomatic occult HBV infections (OBIs), in a densely populated city in India, prompted us to investigate whether PR patients (from varied socioeconomic and immune status) harbor the underlying HBV infections. These cases were also investigated for HHV 6 and 7 infections.

Materials and Methods

DNA from ethylenediaminetetraacetic acid blood samples from PR-diagnosed individuals (n = 13; mostly young adults) and healthy controls (n = 11) were subjected to virus gene-specific polymerase chain reactions (PCRs) for HBV and HHV 6 and 7. PCR products of expected length, when observed, were sequenced (bidirectional) using overlapping primers. Sequences were identified by NCBI BLAST and analyzed by multiple sequence alignment and phylogenetic studies. The blood samples were tested for HBsAg by EIA.

Results

In 5/13 PR samples, only HBV DNA (4/5 being HBsAg negative) was detected, providing first-time evidence that PR may be manifested in asymptomatic HBV carriers. 6/13 cases were HHV 7 (not HHV 6) DNA positive, providing confirmatory molecular genetic evidence for the first time of PR association with HHV 7 from India. Surprisingly, 5/6 HHV 7-positive PR cases were also HBV positive. Overall, 10/13 PR samples showed evidence of HBV infection. 8/13 were OBI, harboring at least one OBI-signature S protein mutation. All healthy controls were HBsAg EIA and PCR negative.

Conclusions

77% of PR patients presented the evidence of underlying HBV infection (genotype D2), suggestive of horizontal HBV transmission. This warrants for mass HBV vaccination. PR patients should be tested for underlying virus infections for appropriate therapy and management.

Novel paradigm for immunotherapy of breast cancer by engaging prophylactic immunity against hepatitis B

BACKGROUND

Immunotherapy of patients suffering from the human epidermal growth factor receptor 2 overexpressing (HER-2(+)) breast cancers with the anti-HER-2 antibodies results in increase of the patients' overall survival. However, no prophylactic vaccine is available against HER-2(+) breast cancers. Although, prophylactic vaccine for human hepatitis B virus (HBV) is very effective.

SPECIFIC AIM

The specific aim of this work was to design, synthesize, and test bio-molecules which would engage prophylactic immunity against hepatitis B virus towards killing breast cancers cells.

METHODS AND RESULTS

By biomolecular engineering, we have created a novel family of biomolecules: antibody (anti-HER-2) × vaccine (HBsAg) engineered constructs (AVEC: anti-HER-2 × HBsAg). These biomolecules were utilized for redirecting, accelerating, and amplifying of the vaccination-induced, prophylactic immunity originally targeted against HBV as therapeutic immunity, newly targeted against HER-2(+) breast cancers. Treatment of the HER-2(+) breast cancer cells with AVEC: anti-HER-2 × HBsAg in blood of the patients, vaccinated with HBsAg, rapidly increased efficacy of killing of HER-2(+) breast cancer cells over that attained with the naked anti-HER-2 antibodies.

CONCLUSION

Novel antibody-vaccine engineered constructs (AVEC) facilitate redirecting, accelerating, and amplifying of prophylactic, HBV vaccination-induced immunity as immunotherapy (RAAVIIT) of HER-2(+) breast cancer. We currently streamline this novel therapeutic paradigm into clinical trials of breast and other cancers.

Novel paradigm for immunotherapy of ovarian cancer by engaging prophylactic immunity against hepatitis B virus

BACKGROUND

Only eight women out of one hundred diagnosed with ovarian epithelial cancers, which progressed to the clinical stage IV, survive 10 years. First line therapies: surgery, chemotherapy, and radiation therapy inflict very serious iatrogenic consequences. Passive immunotherapy of ovarian cancers offers only low efficacy. Prophylactic and therapeutic vaccines for ovarian cancers are not available. Interestingly, prophylactic vaccines for Hepatitis B Viruses (HBV) are very effective.

SPECIFIC AIM

The specific aim of this work was to design, synthesize, and administer biomolecules, which would engage prophylactic, vaccination-induced immunity for HBV towards killing of ovarian cancer cells with high specificity and efficacy.

PATIENTS

Tissue biopsies, ascites, and blood were acquired from the patients, whose identities were entirely concealed in accordance with the Declaration of Helsinki, pursuant to the Institutional Review Board approval, and with the Patients' informed consent.

METHODS AND RESULTS

By biomolecular engineering, we have created a novel family of biomolecules: antibody × vaccine engineered constructs (AVEC: anti-HER-2 × HBsAg). We have collected the blood from the volunteers, and measured the titers of anti-HBV antibodies resulting from the FDA approved and CDC scheduled HBV vaccinations. We have acquired tumor biopsies, ascites, and blood from patients suffering from the advanced ovarian cancers. We have established cultures of HER-2 over-expressing epithelial ovarian cancers: OV-90, TOC-112D, SKOV-3, as well as human ovary surface epithelial (HOSE) and human artery endothelial (HAE) cells. Treatment of the HER-2+ ovarian cancer cells with AVEC: anti-HER-2 × HBsAg, accompanied by administration of blood drawn from patients with high titers of the anti-HBV antibodies, resulted in much higher therapeutic efficacy as compared to treatment with the naked anti-HER-2 antibodies alone and/or with the relevant isotype antibodies. This treatment had practically no effect upon the HOSE and HAE cells.

DISCUSSION

Herein, we report attaining the great improvement in eradication efficacy of ovarian epithelial cancer cells' by engaging prophylactic immunity against HBV; thus creating a novel paradigm for immunotherapy of ovarian cancer. We have accomplished that by designing, synthesis, and administration of AVEC. Therefore, the HBV vaccination acquired immunity mounts immune response against the vaccine, but AVEC redirect, accelerate, and amplify this immune response of all the elements of the native and adaptive immune system against ovarian cancer. Our novel paradigm of immunotherapy is currently streamlined to clinical trials also of other cancers, while also engaging prophylactic and acquired immunity.

CONCLUSION

Novel antibody-vaccine engineered constructs (AVEC) create the solid foundation for redirected, accelerated, and amplified prophylactic, HBV vaccination-induced immunity immunotherapy (RAAVIIT) of ovarian cancers.