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2.
Lancet Gastroenterol Hepatol ; 9(4): 323-332, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38367633

ABSTRACT

BACKGROUND: Hepatitis B virus (HBV) elimination requires expanding and decentralising HBV care services. However, peripheral health facilities lack access to diagnostic tools to assess eligibility for antiviral therapy. Through the Hepatitis B in Africa Collaborative Network (HEPSANET), we aimed to develop and evaluate a score using tests generally available at lower-level facilities, to simplify the evaluation of antiviral therapy eligibility in people living with HBV. METHODS: We surveyed the availability of clinical and laboratory parameters across different health-care levels in sub-Saharan Africa. We used data from the HEPSANET dataset, the largest cross-sectional dataset of treatment-naive people living with HBV in sub-Saharan Africa, to derive and validate the score. Participants from this dataset were included in the analysis if they were aged 18 years or older and had liver fibrosis stages determined by a liver stiffness measurement or liver histopathology. Participants with co-infections or metabolic disorders were excluded. We allocated participants to the derivation and validation sets by geographical site. In the derivation set, we used stepwise logistic regression to identify the best performing parameters for identifying participants that met the 2017 European Association for the Study of the Liver (EASL) criteria. Regression coefficients were converted into integer points to construct simplified algorithms for different health-care levels. In the validation set, we estimated the area under the receiver operating characteristic, sensitivity, and specificity of the simplified algorithm for identifying antiviral therapy eligibility defined by the 2017 EASL criteria. FINDINGS: At 11 sites from eight countries that returned surveys, aspartate aminotransferase (AST), alanine aminotransferase (ALT), and platelet count were generally available at district hospital levels, and hepatitis B e antigen and point-of-care HBV DNA tests were available only at regional and provincial hospital levels or above. Among 2895 participants included from the HEPSANET database (1740 [60·1%] male, 1155 [39·9%] female), 409 (14·1%) met EASL antiviral therapy eligibility criteria. In the derivation set, the optimal district-level hospital score was: ALT (IU/L), less than 40 (0 points), 40-79 (+1), 80 or greater (+2); AST (IU/L), less than 40 (0), 40-79 (+1), 80 or greater (+2); and platelet counts (109/L), less than 100 (+2), 100-149 (+1), 150 or greater (0). When combined with family history and clinical data for decompensated cirrhosis that do not require any biological tests, a cut-off of 2 points or more had a sensitivity and specificity of 82% (95% CI 76-86) and 95% (93-96) to identify treatment-eligible individuals in the derivation set, and 78% (71-85) and 87% (86-89) in the validation set, respectively. INTERPRETATION: Using a score incorporating platelet counts, AST, and ALT, the majority of people living with HBV requiring antiviral therapy can be identified. Our findings suggest that clinical staging can be decentralised down to district hospital level in sub-Saharan Africa. FUNDING: European Association for the Study of the Liver Foundation, John C Martin Foundation. TRANSLATION: For the French translation of the abstract see Supplementary Materials section.


Subject(s)
Hepatitis B, Chronic , Hepatitis B , Humans , Male , Female , Cross-Sectional Studies , Hepatitis B, Chronic/diagnosis , Hepatitis B, Chronic/drug therapy , Hepatitis B/diagnosis , Hepatitis B/drug therapy , Hepatitis B/epidemiology , Hepatitis B virus/genetics , Africa , Antiviral Agents/therapeutic use
3.
Lancet Glob Health ; 12(1): e66-e78, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38097300

ABSTRACT

BACKGROUND: Global elimination of hepatitis B virus (HBV) requires expanded uptake of antiviral therapy, potentially by simplifying testing algorithms, especially in resource-limited countries. We evaluated the effectiveness, cost-effectiveness, and budget impact of three strategies that determine eligibility for anti-HBV treatment, as compared with the WHO 2015 treatment eligibility criteria, in The Gambia. METHODS: We developed a microsimulation model of natural history using data from the Prevention of Liver Fibrosis and Cancer in Africa programme (known as PROLIFICA) in The Gambia, for an HBV-infected cohort of individuals aged 20 years. The algorithms included in the model were a conventional strategy using the European Association for the Study of the Liver (EASL) 2017 criteria, a simplified algorithm using hepatitis B e antigen and alanine aminotransferase (the Treatment Eligibility in Africa for the Hepatitis B Virus [TREAT-B] score), a Treat All approach for all HBV-infected individuals, and the WHO 2015 criteria. Outcomes to measure effectiveness were disability-adjusted life years (DALYs) and years of life saved (YLS), which were used to calculate incremental cost-effectiveness ratios (ICERs) with the WHO 2015 criteria as the base-case scenario. Costs were assessed from a modified social perspective. A budget impact analysis was also done. We tested the robustness of results with a range of sensitiviy analyses including probabilistic sensitivity analysis. FINDINGS: Compared with the WHO criteria, TREAT-B resulted in 4877 DALYs averted and Treat All resulted in 9352 DALYs averted, whereas the EASL criteria led to an excess of 795 DALYs. TREAT-B was cost-saving, whereas the ICER for Treat All (US$2149 per DALY averted) was higher than the cost-effectiveness threshold for The Gambia (0·5 times the country's gross domestic product per capita: $352). These patterns did not change when YLS was the outcome. In a modelled cohort of 5000 adults (aged 20 years) with chronic HBV infection from The Gambia, the 5-year budget impact was $1·14 million for Treat All, $0·66 million for TREAT-B, $1·03 million for the WHO criteria, and $1·16 million for the EASL criteria. Probabilistic sensitivity analysis indicated that among the Treat All, EASL, and TREAT-B algorithms, Treat All would become the most preferred strategy only with a willingness-to-pay threshold exceeding approximately $72 000 per DALY averted or $110 000 per YLS. INTERPRETATION: Although the Treat All strategy might be the most effective, it is unlikely to be cost-effective in The Gambia. A simplified strategy such as TREAT-B might be a cost-saving alternative. FUNDING: UK Research and Innovation (Medical Research Council). TRANSLATION: For the French translation of the abstract see Supplementary Materials section.


Subject(s)
Cost-Effectiveness Analysis , Hepatitis B virus , Adult , Humans , Gambia , Cost-Benefit Analysis , Africa, Western , Antiviral Agents/therapeutic use
4.
BMC Med ; 21(1): 243, 2023 07 04.
Article in English | MEDLINE | ID: mdl-37403107

ABSTRACT

BACKGROUND: Elimination of mother-to-child transmission of hepatitis B virus (HBV) requires infant immunoprophylaxis and antiviral prophylaxis for pregnant women with high viral loads. Since real-time polymerase chain reaction (RT-PCR), a gold standard for assessing antiviral eligibility, is neither accessible nor affordable for women living in low-income and middle-income countries (LMICs), rapid diagnostic tests (RDTs) detecting alternative HBV markers may be needed. To inform future development of the target product profile (TPP) for RDTs to identify highly viremic women, we used a discrete choice experiment (DCE) and elicited preference and trade-off of healthcare workers (HCW) in Africa between the following four attributes of fictional RDTs: price, time-to-result, diagnostic sensitivity, and specificity. METHODS: Through an online questionnaire survey, we asked participants to indicate their preferred test from a set of two RDTs in seven choice tasks with varying levels of the four attributes. We used mixed multinomial logit models to quantify the utility gain or loss generated by each attribute. We attempted to define minimal and optimal criteria for test attributes that can satisfy ≥ 70% and ≥ 90% of HCWs, respectively, as an alternative to RT-PCR. RESULTS: A total of 555 HCWs from 41 African countries participated. Increases in sensitivity and specificity generated significant utility and increases in cost and time-to-result generated significant disutility. The size of the coefficients for the highest attribute levels relative to the reference levels were in the following order: sensitivity (ß = 3.749), cost (ß = -2.550), specificity (ß = 1.134), and time-to-result (ß = -0.284). Doctors cared most about test sensitivity, while public health practitioners cared about cost and midwives about time-to-result. For an RDT with 95% specificity, costing 1 US$, and yielding results in 20 min, the minimally acceptable test sensitivity would be 82.5% and the optimally acceptable sensitivity would be 87.5%. CONCLUSIONS: African HCWs would prefer an RDT with the following order of priority: higher sensitivity, lower cost, higher specificity, and shorter time-to-result. The development and optimization of RDTs that can meet the criteria are urgently needed to scale up the prevention of HBV mother-to-child transmission in LMICs.


Subject(s)
Hepatitis B virus , Pregnant Women , Infant , Female , Pregnancy , Humans , Hepatitis B virus/genetics , Viral Load , Infectious Disease Transmission, Vertical/prevention & control , Sensitivity and Specificity , Antiviral Agents , Health Personnel
6.
Lancet Glob Health ; 11(9): e1383-e1392, 2023 09.
Article in English | MEDLINE | ID: mdl-37517420

ABSTRACT

BACKGROUND: Chronic liver disease is a major cause of premature death in sub-Saharan Africa. Efficacy of antiviral therapy among patients with hepatitis B virus (HBV)-related cirrhosis is not well established in Africa. We described the clinical characteristics and outcomes of patients with cirrhosis and hepatocellular carcinoma in The Gambia and assessed the impact of tenofovir disoproxil fumarate (TDF) on survival of HBV-infected patients with cirrhosis. METHODS: In this prospective cohort study, we followed up adults who were consecutively diagnosed with cirrhosis or hepatocellular carcinoma between 2012 and 2015 in The Gambia, west Africa. Patients with chronic HBV infection and cirrhosis, without hepatocellular carcinoma, were offered TDF. Primary outcome was overall survival. To determine the effect of TDF on survival, we performed a Cox proportional hazard regression model with inverse probability of treatment weighting (IPTW) based on propensity score. FINDINGS: Of 529 patients enrolled in this study, 336 patients (252 with hepatocellular carcinoma and 84 with cirrhosis) were analysed. Patients were predominantly male (253 [75%] men and 83 [25%] women), with a median age of 42 years (IQR 33-55). 276 (84%) of 327 of patients with data were positive for HBV biomarkers, 31 (10%) of 311 were positive for hepatitis C virus antibodies, and 22 (10%) of 223 were positive for hepatitis D virus antibodies. 64% of patients with hepatocellular carcinoma had multifocal tumour, with a median size of 7·5 cm (IQR 5·4-10·8). 173 patients with hepatocellular carcinoma and 70 patients with cirrhosis were included in the survival analysis. Median survival was 1·5 months (95% CI 1·1-2·0) in patients with hepatocellular carcinoma and 17·1 months (11·2-24·0) in patients with cirrhosis (log-rank p<0·0001). In patients with hepatocellular carcinoma, ascites (hazard ratio [HR] 1·78, 95% CI 1·21-2·60), partial or complete portal thrombosis (HR 2·61, 1·58-4·30), and platelet count (HR 1·80, 1·19-2·70) were independent predictive factors of mortality at baseline. In HBV-infected patients with cirrhosis, median turnaround time between cirrhosis diagnosis and TDF initiation was 4·9 months (IQR 3·2-7·3). In IPTW analysis, TDF treatment was associated with improved survival in patients with HBV-related cirrhosis (adjusted HR 0·14, 0·06-0·34; p<0·0001). INTERPRETATION: These results highlight poor survival of patients with cirrhosis or hepatocellular carcinoma as well as the effectiveness of TDF in reducing the premature mortality of patients with cirrhosis and HBV infection. Interventions for early diagnosis and treatment of cirrhosis as well as screening programmes for hepatocellular carcinoma are urgently required in Africa. FUNDING: European Commission and Medical Research Council UK. TRANSLATION: For the French translation of the abstract see Supplementary Materials section.


Subject(s)
Carcinoma, Hepatocellular , Liver Neoplasms , Adult , Humans , Male , Female , Middle Aged , Carcinoma, Hepatocellular/epidemiology , Carcinoma, Hepatocellular/drug therapy , Carcinoma, Hepatocellular/etiology , Antiviral Agents/therapeutic use , Liver Neoplasms/epidemiology , Liver Neoplasms/drug therapy , Liver Neoplasms/etiology , Prospective Studies , Gambia/epidemiology , Tenofovir/therapeutic use , Liver Cirrhosis/complications , Hepatitis B virus , Africa, Western/epidemiology , Treatment Outcome , Retrospective Studies
7.
J Glob Health ; 13: 04004, 2023 Jan 20.
Article in English | MEDLINE | ID: mdl-36655869

ABSTRACT

Background: Clinical management of chronic hepatitis B virus (HBV) infection is complex and access to antiviral treatment remains limited in sub-Saharan Africa. International guidelines recommend monitoring at least annually for disease progression among HBV-infected people not meeting treatment criteria at initial diagnosis. This study aimed to assess the impact and cost-effectiveness of alternative strategies for monitoring. Methods: We used a mathematical model of HBV transmission and natural history, calibrated to all available West African data, to project the population-level health impact, costs and cost-effectiveness of different monitoring strategies for HBV-infected individuals not initially eligible for antiviral treatment. We assumed that these patients were found in the year 2020 in a hypothetical community-based screening programme in The Gambia. Monitoring frequencies were varied between every 5 and every 1 year and targeted different age groups. Results: The currently recommended annual monitoring frequency was likely to be not cost-effective in comparison with other strategies in this setting. 5-yearly monitoring in 15-45-year olds, at US$338 per disability-adjusted life year averted, had the highest probability of being the most effective cost-effective monitoring strategy. Conclusions: Monitoring less frequently than once a year is a cost-effective strategy in a community-based HBV screening and treatment programme in The Gambia, with the optimal strategy depending on the cost-effectiveness threshold. Efficiencies may be gained by prioritising the 15-45-year age group for more intensive monitoring.


Subject(s)
Hepatitis B, Chronic , Hepatitis B , Humans , Hepatitis B, Chronic/diagnosis , Hepatitis B, Chronic/drug therapy , Cost-Benefit Analysis , Gambia , Hepatitis B/diagnosis , Hepatitis B/drug therapy , Antiviral Agents/therapeutic use
9.
Microorganisms ; 10(11)2022 Oct 22.
Article in English | MEDLINE | ID: mdl-36363693

ABSTRACT

To achieve the World Health Organization's (WHO) goals of eradicating viral hepatitis globally by 2030, the regional prevalence and epidemiology of hepatitis B virus (HBV) and hepatitis delta virus (HDV) coinfection must be known in order to implement preventiveon and treatment strategies. HBV/HDV coinfection is considered the most severe form of vira l hepatitis due to it's rapid progression towards cirrhosis, hepatocellular carcinoma, and liver-related death. The role of simplified diagnosticsis tools for screening and monitoring HBV/HDV-coinfected patients is crucial. Many sophisticated tools for diagnoses have been developed for detection of HBV alone as well as HBV/HDV coinfection. However, these advanced techniques are not widely available in low-income countries and there is no standardization for HDV detection assays, which are used for monitoring the response to antiviral therapy. More accessible and affordable alternative methods, such as rapid diagnostic tests (RDTs), are being developed and validated for equipment-free and specific detection of HBV and HDV. This review will provide some insight into both existing and diagnosis tools under development, their applicability in developing countries and how they could increase screening, patient monitoring and treatment eligibility.

10.
J Glob Health ; 12: 04076, 2022 Nov 12.
Article in English | MEDLINE | ID: mdl-36370422

ABSTRACT

Background: To reduce mortality associated with hepatitis B virus (HBV) infection, timely detection of cirrhosis and early-stage hepatocellular carcinoma (HCC) is essential. In low-income countries, however, HBV-infected people have limited access to liver histopathology, a reference test. Recently, Asian studies have suggested the usefulness of an inexpensive serum biomarker called Mac-2 binding protein glycosylation isomer (M2BPGi) in staging liver fibrosis and predicting HCC in HBV-infected patients. Methods: We systematically searched PubMed for studies examining the performance of M2BPGi in staging liver fibrosis in HBV-infected people, published up to September 21, 2021, to elucidate the knowledge gap. We then conducted a cross-sectional study of 339 HBV-infected patients in The Gambia (cirrhosis = 65, HCC = 73, non-cirrhosis non-HCC = 201). We evaluated the association of M2BPGi with cirrhosis and HCC by computing odds ratios (ORs) derived from logistic regression. We also assessed the performance of M2BPGi to stage liver fibrosis in 49 patients who underwent liver biopsy (derivation set) and 217 patients with transient elastography (validation set). Using the derivation set we drew the receiver operating characteristics (ROC) curves to identify optimal M2BPGi thresholds to indicate significant fibrosis and cirrhosis using biopsy as a reference. We then applied these cut-offs to the validation set to obtain its sensitivity and specificity for indicating significant fibrosis and cirrhosis using transient elastography as a reference. Results: The systematic review identified 13 studies, all of which were conducted in East Asia and none in Africa. In The Gambia, positive M2BPGi was significantly associated with both cirrhosis (adjusted OR = 7.8, 95% CI = 3.1-19.7) and HCC (adjusted OR = 10.1, 2.6-40.2). The areas under the ROC curve (AUROC) in the derivation and validation set were 0.62 and 0.78, respectively, to diagnose significant fibrosis, and 0.80 and 0.89, respectively, to diagnose cirrhosis. By applying the optimal cut-offs, the sensitivity and specificity in the validation set were 61.5% and 93.4%, respectively, to diagnose significant fibrosis, and 72.5% and 92.2%, respectively, for cirrhosis. Conclusions: To the best of our knowledge, this is the first evaluation of M2BPGi in HBV-infected African population. The findings supported its accuracy in the diagnosis of cirrhosis in HBV-infected patients in West Africa.


Subject(s)
Carcinoma, Hepatocellular , Hepatitis B , Liver Neoplasms , Humans , Hepatitis B virus , Glycosylation , Cross-Sectional Studies , Liver Cirrhosis/diagnosis , Liver Cirrhosis/complications , Carcinoma, Hepatocellular/diagnosis , Carcinoma, Hepatocellular/complications , Carcinoma, Hepatocellular/metabolism , Hepatitis B/complications , Hepatitis B/diagnosis , Liver Neoplasms/diagnosis , Liver Neoplasms/complications , Liver Neoplasms/metabolism
11.
JHEP Rep ; 4(10): 100533, 2022 Oct.
Article in English | MEDLINE | ID: mdl-36052221

ABSTRACT

Background & Aims: Strategies to implement HBV screening and treatment are critical to achieve HBV elimination but have been inadequately evaluated in sub-Saharan Africa (sSA). Methods: We assessed the feasibility of screen-and-treat interventions in 3 real-world settings (community, workplace, and hospital) in Senegal. Adult participants were screened using a rapid HBsAg point-of-care test. The proportion linked to care, the proportion who had complete clinical staging (alanine transaminase [ALT], viral load, and FibroScan®), and the proportion eligible for treatment were compared among the 3 intervention groups. Results: In 2013-2016, a total of 3,665 individuals were screened for HBsAg in the community (n = 2,153) and in workplaces (n = 1,512); 199/2,153 (9.2%) and 167/1,512 (11%) were HBsAg-positive in the community and workplaces, respectively. In the hospital setting (outpatient clinics), 638 HBsAg-positive participants were enrolled in the study. All infected participants were treatment naïve. Linkage to care was similar among community-based (69.9%), workplace-based (69.5%), and hospital-based interventions (72.6%, p = 0.617). Of HBV-infected participants successfully linked to care, full clinical staging was obtained in 47.5% (66/139), 59.5% (69/116), and 71.1% (329/463) from the community, workplaces, and hospitals, respectively (p <0.001). The proportion eligible for treatment (EASL criteria) differed among community- (9.1%), workplace- (30.4%), and hospital-based settings (17.6%, p = 0.007). Acceptability of antiviral therapy, adherence, and safety at 1 year were very good. Conclusions: HBV screen-and-treat interventions are feasible in non-hospital and hospital settings in Senegal. However, the continuum of care is suboptimal owing to limited access to full clinical staging. Improvement in access to diagnostic services is urgently needed in sSA. Lay summary: Hepatitis B infection is highly endemic in Senegal. Screening for infection can be done outside hospitals, in communities or workplaces. However, the hepatitis B continuum of care is suboptimal in Senegal and needs to be simplified to scale-up diagnosis and treatment coverage.

12.
Lancet Gastroenterol Hepatol ; 7(10): 932-942, 2022 10.
Article in English | MEDLINE | ID: mdl-35961359

ABSTRACT

BACKGROUND: Despite growing concerns about transmissibility and clinical impact, occult hepatitis B virus (HBV) infection has received little attention in the hepatitis elimination agenda. We aimed to estimate the prevalence of occult HBV infection at a global and regional scale and in specific populations. METHODS: For this systematic review and meta-analysis, we searched the MEDLINE, Embase, Global Health, and Web of Science databases for articles published in any language between Jan 1, 2010, and Aug 14, 2019. We included original articles and conference abstracts of any study design that reported the proportion of HBsAg-negative adults (aged ≥18 years) who are positive for HBV DNA (ie, people with occult HBV infection). The prevalence of occult HBV infection was pooled, using the DerSimonian-Laird random-effects model, in the general population and specific groups defined by the type of study participants (blood donors; other low-risk populations; high-risk populations; and people with advanced chronic liver disease), and stratified by HBV endemicity in each country. We also assessed the performance of anti-HBc as an alternative biomarker to detect occult HBV infection. The study was registered with PROSPERO, CRD42019115490. FINDINGS: 305 of 3962 articles were eligible, allowing a meta-analysis of 140 521 993 individuals tested for HBV DNA. Overall, only two studies evaluated occult HBV infection in the general population, precluding unbiased global and regional estimates of occult HBV infection prevalence. In blood donors, occult HBV infection prevalence mirrored HBV endemicity: 0·06% (95% CI 0·00-0·26) in low-endemicity countries, 0·12% (0·04-0·23) in intermediate-endemicity countries, and 0·98% (0·44-1·72), in high-endemicity countries (p=0·0012). In high-risk groups, occult HBV infection prevalence was substantial, irrespective of endemicity: 5·5% (95% CI 2·9-8·7) in low-endemicity countries, 5·2% (2·5-8·6) in intermediate-endemicity countries, and 12·0% (3·4-24·7) in high-endemicity countries. The pooled sensitivity of anti-HBc to identify occult HBV infection was 77% (95% CI 62-88) and its specificity was 76% (68-83). INTERPRETATION: A substantial proportion of people carry occult HBV infection, especially among high-risk groups across the globe and people living in highly endemic countries. Occult HBV infection should be part of the global viral hepatitis elimination strategy. FUNDING: None.


Subject(s)
Hepatitis B, Chronic , Hepatitis B , Adolescent , Adult , DNA, Viral , Hepatitis B/diagnosis , Hepatitis B/epidemiology , Hepatitis B Antibodies , Hepatitis B virus/genetics , Humans , Prevalence
13.
Lancet Gastroenterol Hepatol ; 7(11): 1036-1048, 2022 11.
Article in English | MEDLINE | ID: mdl-35810766

ABSTRACT

Hepatocellular carcinoma is a leading public health concern in sub-Saharan Africa, and it is most prevalent in young adults (median 45 years [IQR 35-57]). Overall, outcomes are poor, with a median survival of 2·5 months after presentation. Major risk factors for hepatocellular carcinoma are hepatitis B virus (HBV), hepatitis C virus, aflatoxin B1 exposure, and alcohol consumption, with metabolic dysfunction-associated fatty liver disease slowly emerging as a risk factor over the past few years. Crucially, these risk factors are preventable and manageable with effective implementation of the HBV birth-dose vaccination, treatment of chronic viral hepatitis, provision of harm reduction services, and by decreasing aflatoxin B1 exposure and harmful alcohol consumption. Primary prevention is central to the management of hepatocellular carcinoma, especially in poorly resourced environments. Effective screening and surveillance programmes with recall policies need to be implemented, because detection and curative management of hepatocellular carcinoma is possible if it is detected at an early stage, even in countries with minimal resources, with appropriate upskilling of medical personnel. The establishment of centres of excellence with advanced diagnostic and therapeutic capabilities within countries should improve hepatocellular carcinoma outcomes and assist in driving the implementation of much needed systematic data systems focused on hepatocellular carcinoma to establish the accurate burden in sub-Saharan Africa. Such data would support the public health importance of hepatocellular carcinoma and provide a strong basis for advocacy, programme development, resource allocation, and monitoring of progress in reducing mortality.


Subject(s)
Carcinoma, Hepatocellular , Hepatitis C , Liver Neoplasms , Aflatoxin B1 , Africa South of the Sahara/epidemiology , Carcinoma, Hepatocellular/diagnosis , Carcinoma, Hepatocellular/epidemiology , Carcinoma, Hepatocellular/etiology , Hepatitis C/complications , Hepatitis C/diagnosis , Hepatitis C/epidemiology , Humans , Liver Neoplasms/diagnosis , Liver Neoplasms/epidemiology , Liver Neoplasms/prevention & control
14.
Expert Rev Mol Diagn ; 22(5): 497-505, 2022 05.
Article in English | MEDLINE | ID: mdl-35574686

ABSTRACT

INTRODUCTION: Chronic infection with hepatitis B virus (HBV) is a leading cause of morbidity and death, especially in sub-Saharan Africa (SSA), 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.


Subject(s)
Hepatitis B Surface Antigens , Hepatitis B , Adult , Africa/epidemiology , Hepatitis B/diagnosis , Hepatitis B/epidemiology , Hepatitis B/therapy , Hepatitis B virus , Humans , Point-of-Care Testing
15.
J Infect Dis ; 226(5): 862-870, 2022 09 13.
Article in English | MEDLINE | ID: mdl-34160616

ABSTRACT

BACKGROUND: Prevalence and clinical outcomes of occult hepatitis B infection (OBI) have been poorly studied in Africa. METHODS: Using the PROLIFICA cohort, we compared the prevalence of OBI between hepatitis B surface antigen (HBsAg)-negative healthy adults screened from the general population (controls) and HBsAg-negative patients with advanced liver disease (cases), and estimated the population attributable fraction for the effect of OBI on advanced liver disease. RESULTS: OBI prevalence was significantly higher among cases (15/82, 18.3%) than controls (31/330, 9.4%, P = .03). After adjusting for age, sex, and anti-hepatitis C virus (HCV) serology, OBI was significantly associated with advanced liver disease (odds ratio, 2.8; 95% confidence interval [CI], 1.3-6.0; P = .006). In HBsAg-negative people, the proportions of advanced liver disease cases attributable to OBI and HCV were estimated at 12.9% (95% CI, 7.5%-18.1%) and 16.9% (95% CI, 15.2%-18.6%), respectively. CONCLUSIONS: OBI is endemic and an independent risk factor for advanced liver disease in The Gambia, West Africa. This implies that HBsAg-negative people with liver disease should be systematically screened for OBI. Moreover, the impact of infant hepatitis B immunization to prevent end-stage liver disease might be higher than previous estimates based solely on HBsAg positivity.


Subject(s)
Hepatitis B, Chronic , Hepatitis B , Hepatitis C , Adult , DNA, Viral , Gambia/epidemiology , Hepacivirus , Hepatitis B/epidemiology , Hepatitis B/prevention & control , Hepatitis B Surface Antigens , Hepatitis B virus , Hepatitis B, Chronic/epidemiology , Hepatitis C/epidemiology , Humans , Prevalence
17.
J Viral Hepat ; 28(7): 1003-1010, 2021 07.
Article in English | MEDLINE | ID: mdl-33749097

ABSTRACT

The clinical utility of quantifying hepatitis B surface antigen (qHBsAg) levels in African subjects with chronic hepatitis B virus (HBV) infection has been poorly documented. From a multicentre cohort of 944 HBV-infected African patients, we aimed to assess whether qHBsAg alone can accurately identify i) those in a HBeAg-negative chronic HBV infection phase at low risk of liver disease progression and ii) those in need of antiviral therapy according to the 2017 EASL guidelines. We analysed 770 HBV mono-infected treatment-naïve patients, mainly males (61%) from West Africa (92%), median age 35 years (IQR: 30-44), median HBV DNA: 95.6 IU/ml (10.0-1,300.0), median qHBsAg 5,498 IU/ml (1,171-13,000) and HBeAg-pos 38 (5%). A total of 464/770 (60.2%) patients were classified as HBeAg-negative chronic infection (median age 36 years (31-46), median ALT 23 IU/l (18-28), median HBV-DNA 33.5 IU/ml (3.8-154.1), median LSM 4.8 kPa (4.1-5.8)) and qHBsAg levels had poor accuracy to identify these subjects with an AUROC at 0.58 (95%CI: 0.54-0.62), sensitivity 55.0% and specificity 55.6%; 118/770 (15.3%) patients were eligible for treatment according to the 2017 EASL criteria. qHBsAg correlated poorly with HBV DNA and had poor accuracy to select patients for antiviral therapy with an AUROC at 0.54 (0.49-0.60), sensitivity 46.6% and specificity 46.9%. In African treatment-naïve HBV-infected subjects, the clinical utility of qHBsAg to identify subjects in HBeAg-negative infection phase or subjects eligible for antiviral therapy seems futile. Whether qHBsAg levels can be used as a predictor of long-term liver complications in Africa needs to be further investigated.


Subject(s)
Hepatitis B, Chronic , Hepatitis B , Adult , DNA, Viral , Hepatitis B Surface Antigens , Hepatitis B e Antigens , Hepatitis B virus/genetics , Hepatitis B, Chronic/diagnosis , Hepatitis B, Chronic/drug therapy , Humans , Male
18.
Dev World Bioeth ; 21(1): 25-30, 2021 Mar.
Article in English | MEDLINE | ID: mdl-32654261

ABSTRACT

COVID-19, caused by a novel coronavirus named SARS-CoV-2, was identified in December 2019, in Wuhan, China. It was first confirmed in sub-Saharan Africa in Nigeria on 27 February 2020 and has since spread quickly to all sub-Saharan African countries, causing more than 111,309 confirmed cases and 2,498 deaths as of 03 June 2020. The lessons learned during the recent Ebola virus disease (EVD) outbreaks in some sub-Saharan African countries were expected to shape and influence the region's responses to COVID-19 pandemic. However, some of the challenges associated with the management of the EVD outbreaks persist and create obstacles for the effective management of the COVID-19 pandemic. This article describes the commonalities between the EVD epidemics and COVID-19 pandemic, with a view to draw on lessons learned to effectively tackle the ongoing pandemic. Key successes, failures and lessons learned from previous EVD outbreaks are discussed. Recommendations on how these lessons can be translated to strengthen the COVID-19 response in sub-Saharan Africa are provided.


Subject(s)
COVID-19/epidemiology , Delivery of Health Care/standards , Disease Outbreaks , Hemorrhagic Fever, Ebola/epidemiology , Public Health Practice/standards , Africa South of the Sahara/epidemiology , Humans , SARS-CoV-2 , Social Stigma
19.
JHEP Rep ; 2(5): 100144, 2020 Oct.
Article in English | MEDLINE | ID: mdl-32904132

ABSTRACT

BACKGROUND & AIMS: Although HBV is a major cause of death in Africa, its genetic variability has been poorly documented. This study aimed to address whether HBV genotype and surface gene variants are associated with HBV-related liver disease in The Gambia. METHODS: We conducted a case-control study nested in the Prevention of Liver Fibrosis and Cancer in Africa programme. Consecutive treatment-naive patients with chronic HBV infection and detectable viral load were recruited: 211 controls with no significant liver disease and 91 cases (56 cirrhosis and 35 HCC cases). HBV genotypes and surface gene variants were determined by Sanger sequencing or next-generation sequencing (NGS) in serum DNA. Aflatoxin B1 (AFB1)-specific codon 249 TP53 mutation was determined by NGS in circulating cell-free plasma DNA. RESULTS: In phylogenetic analysis, 85% of individuals carried HBV genotype E, 14% genotype A, and 1% A/E recombinant viruses. Surface gene variants were more frequently observed in cases (43% and 57% in cirrhosis and HCC cases, respectively) than controls (25%; p <0.001), with preS2 deletions between nucleotides 38-55 (preS2Δ38-55) being the main genetic variant detected. In multivariable analysis, HBeAg seropositivity, low HBsAg levels, and HDV seropositivity were significantly associated with cirrhosis and HCC, whilst older age, higher viral load, genotype A, preS2Δ38-55, and AFB1 exposure were only associated with HCC. There was a multiplicative joint effect of preS2Δ38-55 variants with HBeAg seropositivity (odds ratio [OR] 43.1 [10.4-177.7]), high viral load >2,000 IU/ml (OR 22.7 [8.0-64.9]), HBsAg levels <10,000 IU/ml (OR 19.0 [5.5-65.3]), and AFB1 exposure (OR 29.3 [3.7-230.4]) on HCC risk. CONCLUSIONS: This study identified a hotspot for HBV preS2 deletions as a strong independent factor for HCC in The Gambia, with HBV genotypes and AFB1 exposure contributing to the high liver cancer risk. LAY SUMMARY: Although HBV-related liver disease is highly prevalent in sub-Saharan Africa, the associated virological characteristics are poorly studied. Using clinical data from African patients chronically infected with HBV, an assessment of the virological variability (genotypes and mutations) and exposure to AFB1, a toxin often contaminating food, was carried out. Our results show that HBV genotypes, the presence of a highly prevalent mutant form of HBV, and AFB1 exposure contribute to the high liver cancer risk in this population.

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