Assessing Molecular Point-of-Care Testing and Dried Blood Spot for Hepatitis C Virus Screening in People Who Inject Drugs

Personalized care approaches to hepatitis C therapy: recent advances and future directions

INTRODUCTION

The introduction of direct-acting antivirals (DAAs) has significantly transformed the therapeutic landscape for chronic C hepatitis virus (HCV) infection. However, there is still room for further improvement in optimizing therapy efficacy and minimizing adverse effects.

AREAS COVERED

This review is devoted to the rationale for adopting a personalized approach to HCV therapy. Specifically, we explore the role of host-related factors, such as sex or the presence of comorbidities. We thoroughly examine the implications of commonly encountered comorbidities, including HIV infection, chronic renal disease, liver cirrhosis, and other chronic viral hepatitis infections. Additionally, we discuss the prevalent drug-to-drug interactions between DAAs and other medications, while providing guidance on their management. Finally, we investigate viral-related issues that can influence treatment outcomes, such as viral genotype, quasi-species, and the presence of resistance-associated mutations.

EXPERT OPINION

Despite pivotal trials demonstrating efficacy rates exceeding 90% for currently available DAA regimens, there are still opportunities to optimize therapy outcomes and tailor treatment to each patient. This can be achieved through a meticulous evaluation of the patient's specific clinical conditions and comorbidities, a vigilant approach to manage potential drug interactions, and diligent patient follow-up.

Pharmacy-based screening program to detect hepatitis C in 'baby-boomer' cohorts in western Canada

Background

The estimated prevalence of hepatitis C virus (HCV) in Canada is approximately 1.0%. However, the number of individuals living with HCV but unaware of it is estimated to be 30%-44%. Increased screening programs that are accessible, effective, and feasible are important to ensure treatment and meet WHO elimination goals. We implemented an HCV point of care test (POCT) program in community pharmacies to examine the effectiveness and feasibility in screening.

Methods

Twenty two London Drugs pharmacies in British Columbia and Alberta implemented an HCV POC screening program using OraQuick rapid antibody tests. Consenting patients filled out a 10-question screening questionnaire to examine risk factors. The participants then were tested using the POCT. While waiting for the test (20 minutes), patients were educated on HCV and treatment options.

Results

Three hundred seventy-one participants underwent HCV screening. The most common HCV risk factor was being born between 1945 and 1975 (baby boomer) (93% of cohort), while the second most common was having a tattoo or body piercing (22%). Seven people (2%) tested positive; four were HCV-RNA PCR-positive and were treated, whereas the PCR status of three was unknown as they were lost to follow-up or not tested.

Conclusions

Pharmacy-based POCT was shown to be effective and feasible in the western Canadian context, especially for baby boomers. Sustainable funding for pharmacy screening programs may be considered nationwide to identify HCV-infected persons and help meet elimination goals.

Challenges to Achieving HCV Micro-Elimination in People With HIV in the United States: Provider Perspectives and the Role of Implicit Bias

The prevalence of HIV/HCV (hepatitis C virus) co-infection is high particularly in persons who inject drugs (PWID) and is increasing because of the evolving opioid epidemic in the United States. The introduction of effective antiviral medications for HCV has raised the strategic goal of HCV micro-elimination, and efforts to understand the barriers to treatment are critical. In this study, we explored the provider perspective of factors that inhibit HCV micro-elimination efforts in people with HIV (PWH), including the role of implicit bias and related stigma in providers' health care decision making. We used the mixed-methods approach of nominal group technique (NGT) with 14 participants from 11 different clinics engaged in two virtual focus group sessions (n = 5 and n = 9). Responses from the NGTs were rank ordered during the sessions to identify providers' perspectives of major barriers and facilitators, then identified possible implicit bias after the NGTs concluded. There were 12 responses given for micro-elimination barriers with the three most prioritized being housing instability, medication nonadherence concerns, and inability to motivate patients. Of these, eight were categorized as potential implicit biases. Among the 14 responses given for facilitators of treatment, the three major solutions included distributive models of care, improved provider knowledge, and increased patient engagement. Although the solutions offered were insightful, there was consensus that the individual lives of patients were the root cause of most barriers to care. We recommend further research on behavioral design interventions that promote patients' involvement in decision making and focus on patients' eligibility criteria for HCV treatment as opposed to providers' perceived barriers to treatment.

National viral hepatitis control program in India: Call for update

Viral hepatitis is a serious yet manageable and preventable public health menace that infects about 3 million of people and leads to 1.1 million deaths worldwide every year. An acute episode of viral hepatitis usually subsides on its own, however, if not intervened timely, chronic infection puts people at risk of cirrhosis, liver cancer, and eventually death. In 2015, the global community allied to tackle viral hepatitis, as a result of which combating viral hepatitis target was included in the sustainable development goals (SDGs), and the World Health Organisation (WHO) constituted the first-ever global health sector strategy on viral hepatitis for 2016 to 2021 which is also renewed recently. Conforming to the global commitment, India launched the National Viral Hepatitis Control Program in the year 2018 with the aim to eliminate viral hepatitis as a public health threat by the year 2030. In the Subsequent years, WHO and various other international societies have released updated recommendations with respect to vaccination, prevention of mother-to-child transmission, strategies to increase testing uptake including self-testing, newer diagnostics including point of care and reflex testing approaches, simplified treatment algorithms, expanded treatment eligibility criteria, and simplified service delivery models. With the program being in its fifth year of implementation, there is a need to revamp the operational guidelines based on various global evidence-based advancements in order to attain the ambitious elimination goal by 2030.

Impact of hepatitis C virus point-of-care RNA viral load testing compared with laboratory-based testing on uptake of RNA testing and treatment, and turnaround times: a systematic review and meta-analysis

BACKGROUND

Point-of-care (POC) hepatitis C virus (HCV) RNA nucleic acid test viral load assays are being used increasingly as an alternative to centralised, laboratory-based standard-of-care (SOC) viral load assays to reduce loss to follow-up. We aimed to evaluate the impact of using POC compared with SOC approaches on uptake of HCV RNA viral load testing and treatment, and turnaround times from testing to treatment along the HCV care cascade.

METHODS

We searched PubMed, Embase, and Web of Science for studies published in English between Jan 1, 2016, and April 13, 2022. We additionally searched for accepted conference abstracts (2016-20) not identified in the main search. The contacts directory of the WHO Global Hepatitis Programme was also used to solicit additional studies on use of POC RNA assays. We included studies if they evaluated use of POC HCV RNA viral load with or without a comparator laboratory-based SOC assay, and had data on uptake of viral load testing and treatment, and turnaround times between these steps in cascade. We excluded studies with a sample size of ten or fewer participants. The POC studies were categorised according to whether the POC assay was based onsite at the clinic, in a mobile unit, or in a laboratory. Studies using the POC assay or comparator SOC assays were further stratified according to four models of care: whether HCV testing and treatment initiation were performed in the same or different site, and on the same or a different visit. The comparator was centralised, laboratory-based HCV RNA SOC assays. For turnaround times, we calculated the weighted median of medians with 95% CIs. We analysed viral load testing and treatment uptake using random-effects meta-analysis. The quality of evidence was rated using the GRADE framework. This study is registered with PROSPERO, CRD42020218239.

FINDINGS

We included 45 studies with 64 within-study arms: 28 studies were in people who inject drugs, were homeless, or both; four were in people incarcerated in prison; nine were in the general or mixed (ie, includes high-risk groups) populations; and four were in people living with HIV. All were observational studies. The pooled median turnaround times between HCV antibody test and treatment initiation was shorter with onsite POC assays (19 days [95% CI 14-53], ten arms) than with either laboratory-based POC assays (64 days [64-64], one arm) or laboratory-based SOC assays (67 days [50-67], two arms). Treatment uptake was higher with onsite POC assays (77% [95% CI 72-83], 34 arms) or mobile POC assays (81% [60-97], five arms) than with SOC assays (53% [31-75], 12 arms); onsite and mobile POC assay vs SOC assay p=0·029). For POC and SOC arms, higher RNA viral load testing uptake was seen with the same-site models for testing and treatment than with different-site models (all within-category p≤0·0001). For onsite and mobile POC arms, there was higher treatment uptake for same-site than different-site models (within-category p<0·0001). Four studies had direct within-study POC versus SOC comparisons for RNA viral load testing uptake (pooled relative risk 1·11 [95% CI 0·89-1·38]), and there were ten studies on treatment uptake (1·32 [1·06-1·64]). Overall, the quality of evidence was rated as low.

INTERPRETATION

Compared with use of laboratory-based SOC HCV viral load testing, the use of POC assays was associated with reduced time from antibody test to treatment initiation and increased treatment uptake. The effect of POC viral load testing is greatest when positioned within a simplified care model in which testing and treatment are provided at the same site, and, where possible, on the same day. POC HCV RNA viral load testing is now recommended in WHO guidelines as an alternative strategy to laboratory-based viral load testing.

FUNDING

Unitaid.

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.

Recommendations for the integral diagnosis of chronic viral hepatitis in a single analytical extraction

The Spanish Society of Digestive Pathology (SEPD), the Spanish Association for the Study of the Liver (AEEH), the Spanish Society of Infections and Clinical Microbiology (SEIMC) and its Viral Hepatitis Study Group (GEHEP), and with the endorsement of the Alliance for the Elimination of Viral Hepatitis in Spain (AEHVE), have agreed on a document to carry out a comprehensive diagnosis of viral hepatitis (B, C and D), from a single blood sample; that is, a comprehensive diagnosis, in the hospital and/or at the point of care of the patient. We propose an algorithm, so that the positive result in a viral hepatitis serology (B, C and D), as well as human immunodeficiency virus (HIV), would trigger the analysis of the rest of the virus, including the viral load when necessary, in the same blood draw. In addition, we make two additional recommendations. First, the need to rule out a previous hepatitis A virus (VHA) infection, to proceed with its vaccination in cases where IgG-type studies against this virus are negative and the vaccine is indicated. Second, the determination of the HIV serology. Finally, in case of a positive result for any of the viruses analyzed, there must be an automated alerts and initiate epidemiological monitoring.

Usefulness of dried blood spot samples for monitoring hepatitis C treatment outcome and reinfection among people who inject drugs in a test-and-treat program

Dried blood spots (DBS) are a reliable tool to diagnose viremic hepatitis C virus (HCV) infection. We evaluated the clinical performance of a DBS-based molecular assay for the assessment of cure and reinfection after on-site treatment at a harm reduction center (HRC). Genotyping from DBS samples was also assessed to discriminate reinfection from treatment failure. People who inject drugs (PWID) from an ongoing test-and-treat pilot at the largest HRC in Barcelona were included in the study. HCV-RNA detection from DBS collected after treatment (with follow-up at 12, 36, and 60 weeks) was compared with a molecular point-of-care test using finger-stick blood (GeneXpert). Baseline and follow-up DBS samples were genotyped by NS5B sequencing or commercial real-time PCR. Among treated patients, 193 follow-up DBS samples were tested. The DBS-based assay showed 100% specificity (129/129), and sensitivity ranged from 84.4% to 96.1% according to different viral load cut-offs (from detectable to 3000 IU/mL). Sensitivity as test of cure (follow-up 12) ranged from 85.1% to 97.4%. Among the 64 patients with recurrent viremia, 10.9% had low viral loads (≤1000 IU/mL); HCV genotyping allowed us to classify 73.5% of viremic cases either as reinfection or as treatment failure. DBS samples are useful to assess cure and differentiate reinfection from relapse after HCV antiviral treatment in the real world, facilitating decentralization of treatment and posttreatment follow-up in PWID. However, a fraction of patients presented with low viral loads, limiting viremia detection and genotyping in DBS and, therefore, repeat testing is recommended.

Diagnostic Accuracy of Point-of-Care HCV Viral Load Assays for HCV Diagnosis: A Systematic Review and Meta-Analysis

Despite the widespread availability of curative treatment with direct-acting antivirals, a significant proportion of people with HCV remain undiagnosed and untreated. New point-of-care (PoC) HCV RNA assays that can be used in clinical settings may help expand access to testing and treatment. This study aimed to evaluate the diagnostic performance of PoC HCV viral load assays compared to laboratory-based testing. Methods: We searched three databases for studies published before May 2021 that evaluated PoC HCV RNA assays against a laboratory NAT reference standard (Prospero CRD42021269022). Random effects bivariate models were used to summarize the estimates. Stratified analyses were performed based on geographic region, population (PWID, etc.), and specimen type (serum/plasma or fingerstick; fresh or frozen). We used the GRADE approach to assess the certainty of the evidence. Results: A total of 25 studies were eligible. We evaluated five different commercially available viral load assays. The pooled sensitivity and specificity were 99% (95% CI: 98−99%) and 99% (95% CI: 99−100%), respectively. High sensitivity and specificity were observed across different assays, study settings (including LMICs and HICs), and populations. There was a small but statistically significant reduction in sensitivity for fingersticks compared to serum or plasma samples (98% vs. 100%, p < 0.05), but the specificity was similar between frozen and fresh samples. The evidence was rated as moderate-high certainty. Conclusions: PoC HCV viral load assays demonstrate excellent diagnostic performance in various settings and populations. The WHO now recommends using PoC HCV viral load assays as an additional strategy to promote access to confirmatory viral load testing and treatment.

RT-LAMP-Based Molecular Diagnostic Set-Up for Rapid Hepatitis C Virus Testing

Hepatitis C virus (HCV) infections occur in approximately 3% of the world population. The development of an enhanced and extensive-scale screening is required to accomplish the World Health Organization's (WHO) goal of eliminating HCV as a public health problem by 2030. However, standard testing methods are time-consuming, expensive, and challenging to deploy in remote and underdeveloped areas. Therefore, a cost-effective, rapid, and accurate point-of-care (POC) diagnostic test is needed to properly manage the disease and reduce the economic burden caused by high case numbers. Herein, we present a fully automated reverse-transcription loop-mediated isothermal amplification (RT-LAMP)-based molecular diagnostic set-up for rapid HCV detection. The set-up consists of an automated disposable microfluidic chip, a small surface heater, and a reusable magnetic actuation platform. The microfluidic chip contains multiple chambers in which the plasma sample is processed. The system utilizes SYBR green dye to detect the amplification product with the naked eye. The efficiency of the microfluidic chip was tested with human plasma samples spiked with HCV virions, and the limit of detection observed was 500 virions/mL within 45 min. The entire virus detection process was executed inside a uniquely designed, inexpensive, disposable, and self-driven microfluidic chip with high sensitivity and specificity.

Detection of active hepatitis C in a single visit and linkage to care among marginalized people using a mobile unit in Madrid, Spain

BACKGROUND

The burden of hepatitis C virus (HCV) infection among marginalized people in Spain is high, despite the fact that HCV prevalence has decreased in recent years. We aimed to assess the effectiveness of a simplified point-of-care (PoC) model for screening for active HCV infection via a mobile unit and subsequent linkage to care with the assistance of navigators.

METHODS

We carried out a prospective study on 2001 participants from Madrid, Spain. A nurse and a navigator/educator screened for hepatitis C in a mobile unit, using the OraQuick HCV Rapid Antibody Test and Xpert HCV VL Fingerstick assay. Participants with active HCV were referred to the hospital the same day with a navigator for evaluation and treatment of HCV.

RESULTS

Overall, 1621 (81%) participants had not been exposed to HCV, 380 (18.9%) were positive for HCV antibodies, and 136 (6.8%) had active hepatitis C. Among the latter, 134 (98.5%) received the HCV screening results, 133 (97.8%) had an appointment at the hospital, 126 (92.8%) were seen by a physician once they were at the hospital, and 105 (77.2%) started HCV treatment. Being over 50 years old and a person who uses drugs, particularly people who inject drugs (PWID), was directly associated with active hepatitis C (p<0.05). PWID were the only patients with HCV reinfection (4.3% in people without recent injecting drug use and 5.9% in people with recent injecting drug use). Among PWID, no income and daily alcohol intake were also directly associated with active hepatitis C. People with recent injecting drug use showed the lowest rates of attendance at the hospital (91.8%) and starting HCV treatment (70.4%).

CONCLUSION

HCV screening using a two-step PoC-based strategy and its linkage to care was extremely efficient for identifying and treating marginalized people with active hepatitis C, thanks to the use of a mobile unit with personnel and technical equipment, an interdisciplinary team, and collaboration between institutions.

Characterization of Acute HCV Infection and Transmission Networks in People Who Currently Inject Drugs in Catalonia: Usefulness of Dried Blood Spots

BACKGROUND AND AIMS

Accurate identification of recent HCV infections is critical for tracing the extent and mechanisms of ongoing transmission. We aimed to validate dried blood spot (DBS) samples for the assessment of Hepatitis C virus (HCV) genetic diversity and to determine epidemiological parameters including incidence, determinants of acute infection, and phylogenetic clustering in people who inject drugs (PWID).

APPROACH AND RESULTS

HCV nonstructural protein 5B next-generation sequencing was performed from plasma and/or DBS in 220 viremic PWID from the HepCdetect II study. No significant differences were found in consensus sequences or Shannon entropy (SE) intrahost diversity estimate between paired plasma/DBS specimens. SE values were used to identify acute infections with 93.3% sensitivity (95% CI, 0.81-1.06) and 95.0% specificity (95% CI, 0.88-1.02) in a set of well-defined controls. An acute HCV infection (either primary infection or reinfection) was detected in 13.5% of viremic participants and was associated with age ≤30 years (OR, 8.09), injecting less than daily (OR, 4.35), ≤5 years of injected drug use (OR, 3.43), sharing cocaine snorting straws (OR, 2.89), and being unaware of their HCV status (OR, 3.62). Annualized HCV incidence was estimated between 31 and 59/100 person-years. On phylogenetic analysis, 46.8% of viremic cases were part of a transmission pair or cluster; age ≤30 years (OR, 6.16), acute infection (OR, 5.73), and infection with subtype 1a (OR, 4.78) were independently associated with this condition.

CONCLUSIONS

The results obtained from plasma and DBS characterize PWID with acute infection and those involved in ongoing HCV transmission and allow estimating incidence from cross-sectional data. This information is critical for the design and assessment of targeted harm reduction programs and test-and-treat interventions and to facilitate monitoring of HCV elimination in this key population.

Hepatitis C testing and treatment uptake among young people who use opioids in New York City: A cross-sectional study

Young people who use drugs have a rising hepatitis C (HCV) incidence in the United States, but they may face barriers to testing and treatment adoption due to stigma. We conducted a cross-sectional study of New York City residents aged 18-29 years who reported non-medical prescription opioid and/or heroin use in the past 30 days. Participants were recruited from the community between 2014-2016 via respondent-driven sampling. Participants completed an in-person structured survey that included questions about HCV testing and treatment and received HCV antibody testing. There were 539 respondents: 353 people who inject drugs (PWID) and 186 non-PWID. For PWID, median age was 25 years, 65% were male and 73% non-Hispanic White. For non-PWID, median age was 23 years, 73% were male and 39% non-Hispanic White. 20% of PWID and 54% of non-PWID had never been tested for HCV (P < .001). Years since first injection (aOR 1.16, CI: 1.02-1.32, P = .02) and history of substance use treatment (aOR 3.17, CI: 1.53-6.61, P = .02) were associated with prior testing among PWID. The seroprevalence of HCV among PWID was 25%, adjusted for sampling weights. Of the 75 who were aware of their HCV-positive status, 53% had received HCV-related medical care, and 28% had initiated treatment. HCV prevalence among young PWID is high, and many have never been tested. Injection experience and treatment engagement is associated with testing. Interventions to increase testing earlier in injection careers, and to improve linkage to HCV treatment, will be critical for young PWID.

HCV screening based on dried blood samples and linkage to care in people who use drugs: A prospective study

BACKGROUND

The burden of hepatitis C virus (HCV) infection among people who use drugs (PWUDs) is considerable. We aimed to screen for HCV infection using the fingerstick dried blood spot (DBS) test and to describe the cascade of hepatitis C care among PWUDs in Madrid, Spain. We also evaluated the prevalence of hepatitis B virus (HBV) and hepatitis D virus (HDV) in this population.

METHODS

We carried out a prospective study and collected samples and epidemiological data using a mobile unit. Viral infections were tested by immunoassay and RT-PCR assay. PWUDs with a positive result were contacted and referred to a specialized health center to confirm and treat the HCV infection.

RESULTS

We studied 529 PWUD samples; 49.7% were from persons who had previously used injection drugs (IDUs). Of these, 152 (28.7%) were positive for HCV antibodies, 122 (23.1%) for HCV RNA, 23 (4.3%) for HBsAg, and two (0.4%) for HDV antibodies (8.7% of those with hepatitis B). People who inject drugs (PWID) more frequently had positive HCV antibody titers (52% vs. 7.3%; p<0.001) and a positive HCV RNA test result (40.2% vs. 7.3%; p<0.001) than non-PWID. The time from sample collection to test results was 19 days. The next 104 individuals (85.2%) with active HCV infection were contacted to report their HCV test results. Of these, 63 (51.6%) had an appointment, 62 (50.8%) were evaluated in the hospital, and 56 (45.9%) started HCV therapy.

CONCLUSION

HCV screening using fingerstick DBS was an excellent tool for determining HCV prevalence and other chronic hepatitis viruses (HBV and HDV) in PWUDs. However, linkage to care was limited, mainly with respect to the initiation of HCV therapy.

Evaluation of dried blood spot testing using the Abbott Alinity i

BACKGROUND

The West of Scotland Specialist Virology Centre currently uses the Abbott Architect for DBS serology. The new Abbott Alinity i will replace the Architect in our laboratory. In this study, mock and stored patient DBS samples were tested on both platforms and results compared.

STUDY DESIGN

Mock DBS were made from whole blood where patient results were known (38 negative samples and 141 positive samples; 39 HIV Antigen/Antibody (Ag/Ab), 35 HCV IgG antibody (HCVG), 34 HBV core IgG (HBCG) and 33 HBsAg). Mock DBS were tested on both Abbott platforms. Stored patient DBS samples (132 negative and 263 positive: 9 HIVAg/Ab, 10 HBsAg, 52 HBCG and 60 HCVG) previously tested on the Architect were retested on the Alinity i.

RESULTS

Mock DBS showed good correlation between the Architect and Alinity i for the HIV Ag/Ab,HBCG and HCVG assays. A poorer correlation occurred with HBsAg, the Alinity i reported HBsAg positives at a lower value compared to the Architect. The coefficient of variation for intra-assay variation was 1.69 % (HIVAg/Ab), 3.25 % (HCVG), 1.68 % (HBsAg) and 1.95 % (HBCG). The sensitivity and specificity was determined based on results from the mock and patient samples. At S/Co cut-off 1.0 both HIV and HBsAg had a sensitivity of 100 %. A cut-off 0.8 gave a sensitivity of 95.83 % (95 % CI 89.67%-98.85%) for HCVG and 0.3 gave a sensitivity of 98.8 % (CI 93.69%-99.97%) for HBCG.

DISCUSSION

The alinity i compared well against the architect and can be used to test DBS samples.