Model-based cost-effectiveness estimates of testing strategies for diagnosing hepatitis C virus infection in Central and Western Africa

REASSURED evaluation of the Bioline HCV point-of-care testing for diagnosing hepatitis C virus infection in primary healthcare settings of Ghana: a study protocol

INTRODUCTION

Hepatitis C virus (HCV) infection is a silent epidemic that needs a comprehensive and contextualised approach to manage. Access to readily available, affordable and acceptable HCV point-of-care (POC) in vitro diagnostics (IVDs) is equally required to meet the global HCV goals. However, most guidelines for evaluating these IVDs such as the WHO prequalification process and country-specific standards disproportionately focus on diagnostic performance. The real-time connectivity, ease of specimen collection, affordability, sensitivity, specificity, user-friendliness, rapidity and robustness, equipment-free or simplicity and deliverability to end-users (REASSURED) criteria provide a holistic and user-oriented evaluation of the IVDs in the populations they are meant to be used. Therefore, as part of a multinational study in sub-Saharan Africa, we will conduct an evaluation of the Bioline HCV POC test for diagnosing HCV infection in primary healthcare settings of Ghana using the REASSURED criteria.

METHODS AND ANALYSIS

This field evaluation will be conducted in three phases. The first phase will use a cross-sectional field evaluation study design to evaluate the diagnostic performance of the Bioline HCV POC test. The second phase will use mixed methods to ascertain operational characteristics and users' perceptions. In the third phase, a cross-sectional survey will be used to estimate the costs of accessing HCV diagnostics services using three proposed HCV testing models to inform the affordability of the testing pathways and linkage to care in the primary healthcare clinics. This phase will run concurrently with the second phase of the study. Thematic content analysis and quantitative data analysis will be performed using ATLAS.ti V.23.0.6 and StataCorp LLC's Stata statistical software V.16.0, respectively.

ETHICS AND DISSEMINATION

The study protocol has been reviewed and fully approved by the Faculty of Health Sciences Research Ethics Committee, University of Pretoria (281/2023) and the Ghana Health Service Ethics Review Committee (GHS-ERC013/08/23). This diagnostic trial has also been registered in the Pan African Clinical Trial Registry (PACTR202410837698664). The findings of the study will be presented in relevant peer-reviewed journals, at local and international conferences, and to all stakeholders involved.

Diagnostic performance of dried blood spot hepatitis C virus core antigen testing for hepatitis C screening: A systematic review and meta-analysis

Dried blood spot (DBS) sampling is increasingly used for hepatitis C virus (HCV) screening. HCVcAg testing offers a faster and more streamlined approach to diagnosing HCV infection. We conducted a systematic review and meta-analysis to assess the diagnostic performance of the Abbott ARCHITECT HCV Ag assay for screening active HCV infection using DBS samples. Eight studies (n = 1229) were selected among all published studies available up to October 4, 2024, in different databases with a search strategy registered (PROSPERO: CRD42022363975). The gold standard method was the HCV PCR test. Data were analyzed using the MIDAS module in STATA with a random effects model. Combined diagnostic accuracy measures were as follows: sensitivity 85%, specificity 100%, positive likelihood ratio (PLR) 233.1, negative likelihood ratio (NLR) 0.15, and summary receiver operating characteristic (SROC) 0.99. Likelihood ratios and Fagan's nomogram suggested that the HCVcAg assay with DBS samples can confirm or rule out active HCV infection with over 92% accuracy in high-prevalence settings (≥5%). However, in low-prevalence settings (≤1%), a confirmatory test must be required for positive results. The ability of the test to identify people without HCV infection was high regardless of HCV prevalence, with an error rate of less than 3%. This meta-analysis is subject to limitations, particularly due to the number of included studies and significant heterogeneity among them. HCV screening using the Abbott ARCHITECT HCV Ag assay with DBS samples showed excellent diagnostic performance, but its external validity may be limited when HCV prevalence is low (≤1%).

Molecular Point-of-Care Testing for Hepatitis C: Available Technologies, Pipeline, and Promising Future Directions

Hepatitis C virus (HCV) remains a major public health problem, despite the availability of effective treatments. In many areas, the ability to diagnose HCV infection at the point of care is key to scaling up access to care and treatment. To achieve this, an accurate, easy-to-use, and affordable diagnostic tool is required-this would enable decentralized testing and the creation of one-stop centers to eliminate gaps in the care cascade, which would help reach the millions of people with undiagnosed HCV infection in low- and middle-income countries and high-risk populations in high-income countries. In this review, we examine the current state of point-of-care molecular technologies, the advantages and limitations of currently available devices (both near- and true-point-of-care), the potential of molecular testing to transform diagnostic medicine in the future, and the challenges that need to be addressed for broader adoption of this technology in routine clinical practice.

A handheld luminometer with sub-attomole limit of detection for distributed applications in global health

Luminescence is ubiquitous in biology research and medicine. Conceptually simple, the detection of luminescence nonetheless faces technical challenges because relevant signals can exhibit exceptionally low radiant power densities. Although low light detection is well-established in centralized laboratory settings, the cost, size, and environmental requirements of high-performance benchtop luminometers are not compatible with geographically-distributed global health studies or resource-constrained settings. Here we present the design and application of a ~$700 US handheld, battery-powered luminometer with performance on par with high-end benchtop instruments. By pairing robust and inexpensive Silicon Photomultiplier (SiPM) sensors with a low-profile shutter system, our design compensates for sensor non-idealities and thermal drift, achieving a limit of detection of 1.6E-19 moles of firefly luciferase. Using these devices, we performed two pilot cross-sectional serology studies to assess sars-cov-2 antibody levels: a cohort in the United States, as well as a field study in Bangladesh. Results from both studies were consistent with previous work and demonstrate the device's suitability for distributed applications in global health.

Comparison of effectiveness and cost of different HCV testing strategies in high-risk populations in China

High-risk populations are the predominant populations affected by hepatitis C virus (HCV) infection, and there is an urgent need for efficient and cost-effective HCV testing strategies for high-risk populations to identify potential undiagnosed HCV-infected individuals. This study compared several commonly used testing strategies and conducted effectiveness and cost analysis to select the appropriate testing strategy for diagnosing HCV infection in high-risk populations. Among the 2093 samples from high-risk populations in this study, 1716 were HCV negative, 237 were current HCV infection, 137 were past HCV infection, and three were acute early HCV infection. It was found that out of 237 patients with HCV current infection, Strategy A could detect 225 cases, with a missed detection rate of 5.06%, and the total cost was 33 299 RMB. In addition, Strategy B could detect 237 cases of current HCV infection, and the HCV missed detection rate was 0.00%, and the total cost was 147 221 RMB. While 137 cases of past HCV infection could be distinguished by strategy C, but 14 cases with current HCV infection were missed, with an HCV-positive missed detection rate of 5.91%, and the total cost for Strategy C was 43 059 RMB. In conclusion, in high-risk populations, the HCV positivity rate is typically higher. If feasible, the preferred approach is to directly conduct HCV RNA testing, which effectively minimizes the risk of missing cases. However, in situations with limited resources, it is advisable to initially choose a highly sensitive method for anti-HCV screening, followed by HCV RNA testing on reactive samples.

Point-of-Care Testing for Hepatitis Viruses: A Growing Need

Viral hepatitis, caused by hepatitis A virus (HAV), hepatitis B virus (HBV), hepatitis C virus (HCV), hepatitis D virus (HDV), or hepatitis E virus (HEV), is a major global public health problem. These viruses cause millions of infections each year, and chronic infections with HBV, HCV, or HDV can lead to severe liver complications; however, they are underdiagnosed. Achieving the World Health Organization's viral hepatitis elimination goals by 2030 will require access to simpler, faster, and less expensive diagnostics. The development and implementation of point-of-care (POC) testing methods that can be performed outside of a laboratory for the diagnosis of viral hepatitis infections is a promising approach to facilitate and expedite WHO's elimination targets. While a few markers of viral hepatitis are already available in POC formats, tests for additional markers or using novel technologies need to be developed and validated for clinical use. Potential methods and uses for the POC testing of antibodies, antigens, and nucleic acids that relate to the diagnosis, monitoring, or surveillance of viral hepatitis infections are discussed here. Unmet needs and areas where additional research is needed are also described.

Optimizing point-of-care testing strategies for diagnosis and treatment of hepatitis C virus infection in Australia: a model-based cost-effectiveness analysis

Background

Timely diagnosis and treatment of hepatitis C virus (HCV) is critical to achieve elimination goals. This study evaluated the cost-effectiveness of point-of-care testing strategies for HCV compared to laboratory-based testing in standard-of-care.

Methods

Cost-effectiveness analyses were undertaken from the perspective of Australian Governments as funders by modelling point-of-care testing strategies compared to standard-of-care in needle and syringe programs, drug treatment clinics, and prisons. Point-of-care testing strategies included immediate point-of-care HCV RNA testing and combined point-of-care HCV antibody and reflex RNA testing for HCV antibody positive people (with and without consideration of previous treatment). Sensitivity analyses were performed to investigate the cost per treatment initiation with different testing strategies at different HCV antibody prevalence levels.

Findings

The average costs per HCV treatment initiation by point-of-care testing, from A$890 to A$1406, were up to 35% lower compared to standard-of-care ranging from A$1248 to A$1632 depending on settings. The average costs per treatment initiation by point-of-care testing for three settings ranged from A$1080 to A$1406 for RNA, A$960-A$1310 for combined antibody/RNA without treatment history consideration, and A$890-A$1189 for combined antibody/RNA with treatment history consideration. When HCV antibody prevalence was <74%, combined point-of-care HCV antibody and point-of-care RNA testing were the most cost-effective strategies. Modest increases in treatment uptake by 8%-31% were required for immediate point-of-care HCV RNA testing to achieve equivalent cost per treatment initiation compared to standard-of-care.

Interpretation

Point-of-care testing is more cost-effective than standard of care for populations at risk of HCV. Testing strategies combining point-of-care HCV antibody and RNA testing are likely to be cost-effective in most settings.

Funding

National Health and Medical Research Council.

Assessing feasibility of a modified same-day test-and-treat model for hepatitis C among rural people who inject drugs

BACKGROUND

Despite advancements in hepatitis C virus (HCV) treatment, low uptake among hard-to-reach populations remains a global issue. The current study aimed to assess the feasibility of a modified same-day test-and-treat model in improving HCV care for people who inject drugs (PWID) living in resource-constrained rural areas.

METHODS

A pilot study was conducted in four primary healthcare (PHC) centers in Malaysia. The model's key features included on-site HCV ribonucleic acid (RNA) testing using a shared GeneXpert® system; noninvasive biomarkers for cirrhosis diagnosis; and extended care to PWID referred from nearby PHC centers and outreach programs. The feasibility assessment focused on three aspects of the model: demand (i.e., uptake of HCV RNA testing and treatment), implementation (i.e., achievement of each step in the HCV care cascade), and practicality (i.e., ability to identify PWID with HCV and expedite treatment initiation despite resource constraints).

RESULTS

A total of 199 anti-HCV-positive PWID were recruited. They demonstrated high demand for HCV care, with a 100% uptake of HCV RNA testing and 97.4% uptake of direct-acting antiviral treatment. The rates of HCV RNA positivity (78.4%) and sustained virologic response (92.2%) were comparable to standard practice, indicating the successful implementation of the model. The model was also practical, as it covered non-opioid-substitution-therapy-receiving individuals and enabled same-day treatment in 71.1% of the participants.

CONCLUSIONS

The modified same-day test-and-treat model is feasible in improving HCV care for rural PWID. The study finding suggests its potential for wider adoption in HCV care for hard-to-reach populations.

Quality Assurance for Hepatitis C Virus Point-of-Care Diagnostics in Sub-Saharan Africa

As part of a multinational study to evaluate the Bioline Hepatitis C virus (HCV) point-of-care (POC) testing in sub-Saharan Africa (SSA), this narrative review summarises regulatory standards and quality indicators for validating and approving HCV clinical diagnostics. In addition, this review also provides a summary of their diagnostic evaluations using the REASSURED criteria as the benchmark and its implications on the WHO HCV elimination goals 2030.

Hepatitis C virus infection screening reduces mortality and is cost-effective independently of the intervention test

INTRODUCTION

Chronic infection due to hepatitis C virus (HCV) is frequently asymptomatic even in advanced stages of liver disease. Implementation of a screening program based on different HCV tests may enable an earlier diagnosis of HCV liver disease and subsequent application of highly effective treatment.

PATIENTS AND METHODS

A Markov model which compares three different screening strategies for hepatitis C versus no screening in low-risk prevalence (general population) and high-risk prevalence population (people who inject drugs or prison population) was designed, taking into account age at the start of screening and participation. The three strategies were: 1) serological detection of antibodies against the HCV, 2) dried blood spot test (DBS) to detect antibodies against HCV and 3) detection of RNA from HCV. Quality-adjusted life-years (QALY) were taken as a measurement of effectiveness. The incremental cost-effectiveness ratio (ICER) was calculated and a deterministic and probabilistic sensitivity analysis was performed.

RESULTS

All three screening strategies were found to be cost-effective with an ICER of €13,633, €12,015 and €12,328/QALY for AntiHCV, DBS-AntiHCV and DBS-RNA HCV, respectively. There was a decrease in mortality due to liver disease in comparison to no screening for AntiHCV (40.7% and 52%), DBS-AntiHCV (45% and 80%) and DBS-RNA HCV (45.2% and 80%) for low-prevalence and high-prevalence populations, respectively.

CONCLUSION

All test interventions for HCV screening are cost-effective for the early detection of HCV infection, also achieving a reduction in mortality. Thus, implementation of screening programs for HCV should not be halted by decisions on monetary policy.

Hepatitis C virus: A critical approach to who really needs treatment

Introduction of effective drugs in the treatment of hepatitis C virus (HCV) infection has prompted the World Health Organization to declare a global eradication target by 2030. Propositions have been made to screen the general population and treat all HCV carriers irrespective of the disease status. A year ago the new severe acute respiratory syndrome coronavirus 2 virus appeared causing a worldwide pandemic of coronavirus disease 2019 disease. Huge financial resources were redirected, and the pandemic became the first priority in every country. In this review, we examined the feasibility of the World Health Organization elimination program and the actual natural course of HCV infection. We also identified and analyzed certain comorbidity factors that may aggravate the progress of HCV and some marginalized subpopulations with characteristics favoring HCV dissemination. Alcohol consumption, HIV coinfection and the presence of components of metabolic syndrome including obesity, hyperuricemia and overt diabetes were comorbidities mostly responsible for increased liver-related morbidity and mortality of HCV. We also examined the significance of special subpopulations like people who inject drugs and males having sex with males. Finally, we proposed a different micro-elimination screening and treatment program that can be implemented in all countries irrespective of income. We suggest that screening and treatment of HCV carriers should be limited only in these particular groups.

Evaluation of Hepatitis C Virus Core Antigen Assay in a Resource-Limited Setting in Pakistan

The diagnosis of Hepatitis C virus (HCV) infection can be challenging due to its cost and a lack of access to centralized testing. There is an urgent need to develop simplified HCV testing algorithms. The aim of this study was to evaluate the performance characteristics of a Hepatitis C core antigen (HCVcAg) assay in a decentralized, resource-limited setting. This is a descriptive cross-sectional study from a highly endemic area of Karachi, Pakistan. Between October 2019 and July 2020, subjects aged 12 years and above who screened positive for HCV antibodies were simultaneously tested for HCV RNA (Xpert HCV Viral Load, GeneXpert^® IV, Cepheid, France) and HCVcAg (ARCHITECT HCV Ag assay, Abbott^® Diagnostics) to confirm active HCV infection. An Abbott ARCHITECT^® i1000SR Immunoassay Analyser was installed at a local district hospital as a point-of-care (POC) facility for HCVcAg testing, while samples for HCV RNA were tested in a central lab. Two hundred individuals (mean age 46.4 ± 14.5 years, 71.5% females), who screened positive for HCV antibody, were included in the study. HCV RNA was detected in 128 (64.0%) while HCVcAg was reactive in 119 (59.5%) cases. Performance of the Immunoassay Analyser was excellent with a higher throughput and quicker readout value compared to the GeneXpert System. The sensitivity and specificity of HCVcAg (≥10 fmol/L) at HCV RNA thresholds of ≥12 was 99.1% (95% CI: 95–100%) and 87.6% (95%CI: 78.4–94%). A strong agreement was observed between the HCVcAg assay and HCV RNA. The ARCHITECT HCV Ag assay showed high sensitivity and specificity compared to HCV RNA in a decentralized, resource-limited setting. It can therefore be used as a confirmatory test in HCV elimination programs, particularly for low-income countries such as Pakistan.

Improving Linkage to Care of Hepatitis C: Clinical Validation of GeneXpert® HCV Viral Load Point-of-Care Assay in Indonesia

Hepatitis C virus (HCV) infection large-scale diagnosis and treatment are hampered by lack of a simple, rapid, and reliable point-of-care (POC) test, which poses a challenge for the elimination of hepatitis C as a public health problem. This study aimed to evaluate Cepheid Xpert^® HCV Viral Load performance in comparison with the Roche Cobas^® TaqMan^® HCV Test using serum samples of HCV-infected patients in Indonesia. Viral load quantification was performed on 243 anti-HCV positive patients’ samples using both Xpert HCV VL and Roche HCV tests, followed by HCV genotyping by reverse hybridization. Strength of the relationship between the assays was measured by Pearson correlation coefficient, while level of agreement was analyzed by Deming regression and Bland–Altman plot analysis using log₁₀-transformed viral load values. Quantifiable viral load was detected in 180/243 (74.1%), with Xpert HCV VL sensitivity of 100% (95% CI 0.98, 1.00) and specificity of 98.4% (95% CI 0.91, 0.99) based on the Roche HCV test, while HCV genotypes were determined in 172/180 (95.6%) samples. There was a good correlation between both assays (r = 0.97, P < 0.001), overall and per genotype, with good concordance by Deming regression and a mean difference of −0.25 log₁₀ IU/mL (95% CI −0.33, −0.18) by Bland–Altman plot analysis. Xpert HCV VL test was demonstrated as a POC platform with good performance for HCV diagnosis and treatment decision that would be beneficial for decentralized services in resource-limited areas. HCV testing sites, alongside additional GeneXpert modular systems distributed toward the fight against COVID-19, could ensure some continuity, once this pandemic is controlled.

An intervention to increase hepatitis C virus diagnosis and treatment uptake among people in custody in Iran

BACKGROUND

Iran is among countries with high opioid agonist therapy (OAT) coverage in prisons, which provides an infrastructure to increase feasibility of HCV programs. We aimed to evaluate the impact of an intervention to improve HCV screening, diagnosis, and treatment, including alongside the provision of OAT, in an Iranian prison.

METHODS

During July-December 2018, in the Gorgan prison, all incarcerated adults (>18 years) received HCV antibody rapid testing and, if positive, provided a venepuncture sample for HCV RNA testing. Participants with positive RNA received direct-acting antiviral (DAA) therapy [(Sofosbuvir/Daclatasvir) for 24 or 12 weeks, respectively, for those with and without cirrhosis]. Response to treatment was measured by the sustained virological response at 12 weeks post-treatment (SVR12).

RESULTS

Among 2015 incarcerated people with a median age of 35 years (IQR:29-41), the majority were male (97%), had not finished high school (68%), and had a history of drug use (71%), of whom 15% had ever injected drugs. A third of participants were receiving OAT, including 54% of those who had ever injected. HCV antibody prevalence was 6.7%, and RNA was detected in 4.6% of all participants; this prevalence was 32.6% and 24.7% among those with a history of injection, respectively. Treatment uptake was 82% (75/92) and was similar among people on OAT and those with a history of injection (81%). The majority completed treatment in prison and were available for SVR12 assessment (71%, 53/75). Achieved SVR12 was 100% (53/53) based on the available case analysis; those who did not have available SVR12 were released either prior to treatment initiation or completion (n = 39).

CONCLUSION

The availability of OAT infrastructure should be considered as an opportunity for enhancing HCV care in prisons. Where resources are limited, the prison harm reduction network could be used to design targeted HCV programs among people who are at higher risk of infection.

HCV Diagnosis and Sequencing Using Dried Blood Spots from Patients in Kinshasa (DRC): A Tool to Achieve WHO 2030 Targets

The World Health Organization has established an elimination plan for hepatitis C virus (HCV) by 2030. In Sub-Saharan Africa (SSA) access to diagnostic tools is limited, and a number of genotype 4 subtypes have been shown to be resistant to some direct-acting antivirals (DAAs). This study aims to analyze diagnostic assays for HCV based on dried blood spots (DBS) specimens collected in Kinshasa and to characterize genetic diversity of the virus within a group of mainly HIV positive patients. HCV antibody detection was performed on 107 DBS samples with Vidas® anti-HCV and Elecsys anti-HCV II, and on 31 samples with INNO-LIA HCV. Twenty-six samples were subjected to molecular detection. NS3, NS5A, and NS5B regions from 11 HCV viremic patients were sequenced. HCV seroprevalence was 12.2% (72% with detectable HCV RNA). Both Elecsys Anti-HCV and INNO-LIA HCV were highly sensitive and specific, whereas Vidas® anti-HCV lacked full sensitivity and specificity when DBS sample was used. NS5B/NS5A/NS3 sequencing revealed exclusively GT4 isolates (50% subtype 4r, 30% 4c and 20% 4k). All 4r strains harbored NS5A resistance-associated substitutions (RAS) at positions 28, 30, and 31, but no NS3 RAS was detected. Elecsys Anti-HCV and INNO-LIA HCV are reliable methods to detect HCV antibodies using DBS. HCV subtype 4r was the most prevalent among our patients. RASs found in subtype 4r in NS5A region confer unknown susceptibility to DAA.