Performance of rapid hepatitis C virus antibody assays among high- and low-risk populations

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.

Assessing potential insights of an imperfect testing strategy: Parameter estimation and practical identifiability using early COVID-19 data in India

A deterministic model with testing of infected individuals has been proposed to investigate the potential consequences of the impact of testing strategy. The model exhibits global dynamics concerning the disease-free and a unique endemic equilibrium depending on the basic reproduction number when the recruitment of infected individuals is zero; otherwise, the model does not have a disease-free equilibrium, and disease never dies out in the community. Model parameters have been estimated using the maximum likelihood method with respect to the data of early COVID-19 outbreak in India. The practical identifiability analysis shows that the model parameters are estimated uniquely. The consequences of the testing rate for the weekly new cases of early COVID-19 data in India tell that if the testing rate is increased by 20% and 30% from its baseline value, the weekly new cases at the peak are decreased by 37.63% and 52.90%; and it also delayed the peak time by four and fourteen weeks, respectively. Similar findings are obtained for the testing efficacy that if it is increased by 12.67% from its baseline value, the weekly new cases at the peak are decreased by 59.05% and delayed the peak by 15 weeks. Therefore, a higher testing rate and efficacy reduce the disease burden by tumbling the new cases, representing a real scenario. It is also obtained that the testing rate and efficacy reduce the epidemic's severity by increasing the final size of the susceptible population. The testing rate is found more significant if testing efficacy is high. Global sensitivity analysis using partial rank correlation coefficients (PRCCs) and Latin hypercube sampling (LHS) determine the key parameters that must be targeted to worsen/contain the epidemic.

Performance of rapid test for antibodies to hepatitis C virus (anti-HCV) in hemodialysis patients and kidney transplant recipients

Rapid tests (RT) have been widely used for screening of hepatitis C virus (HCV) in general population, but its performance in hemodialysis (HD) patients and mainly in kidney-transplant recipients (RTx) is less known. The aim of this study was to evaluate the accuracy of RT for detection of anti-HCV in HD and RTx patients. Patients were prospectively included subdivided in four groups according to the positivity for anti-HCV detected by conventional serology: (1) HD patients anti-HCV +, (2) HD patients anti-HCV -, (3) RTx patients anti-HCV +, and (4) RTx patients anti-HCV -. All patients were retested for HCV using the commercial kit Alere HCV^® Bioeasy Rapid Test (Bioeasy Diagnóstica LTDA-Minas Gerais, Brazil) in capillary whole blood samples. During the period of study were included 46 HD patients anti-HCV+, 62 HD patients anti-HCV -, 53 RTx patients anti-HCV + and 56 RTx patients anti-HCV -. In patients on HD, the RT showed sensitivity (S), specificity (SP), positive predictive value (PPV), negative predictive value (NPV), and accuracy of 100%. In RTx patients, S of 96%, SP of 100%, PPV of 100% and NPV of 97% were found (accuracy of 98%). In conclusion, in patients on HD there was 100% agreement between RT and the conventional immunoassay. In the RTx group, although the agreement was not 100%, the RT performed very well when compared to conventional serology. This study demonstrates that the RT can be an alternative to conventional serology in HCV screening of patients on HD and RTx.

Hepatitis C Diagnosis: Simplified Solutions, Predictive Barriers, and Future Promises

The simplification of current hepatitis C diagnostic algorithms and the emergence of digital diagnostic devices will be very crucial to achieving the WHO's set goals of hepatitis C diagnosis (i.e., 90%) by 2030. From the last decade, hepatitis C diagnosis has been revolutionized by the advent and approval of state-of-the-art HCV diagnostic platforms which have been efficiently implemented in high-risk HCV populations in developed nations as well as in some low-to-middle income countries (LMICs) to identify millions of undiagnosed hepatitis C-infected individuals. Point-of-care (POC) rapid diagnostic tests (RDTs; POC-RDTs), RNA reflex testing, hepatitis C self-test assays, and dried blood spot (DBS) sample analysis have been proven their diagnostic worth in real-world clinical experiences both at centralized and decentralized diagnostic settings, in mass hepatitis C screening campaigns, and hard-to-reach aboriginal hepatitis C populations in remote areas. The present review article overviews the significance of current and emerging hepatitis C diagnostic packages to subvert the public health care burden of this 'silent epidemic' worldwide. We also highlight the challenges that remain to be met about the affordability, accessibility, and health system-related barriers to overcome while modulating the hepatitis C care cascade to adopt a 'test and treat' strategy for every hepatitis C-affected individual. We also elaborate some key measures and strategies in terms of policy and progress to be part of hepatitis C care plans to effectively link diagnosis to care cascade for rapid treatment uptake and, consequently, hepatitis C cure.

Antibody Responses in Hepatitis C Infection

Antibody responses in hepatitis C virus (HCV) have been a rather mysterious research topic for many investigators working in the field. Chronic HCV infection is often associated with dysregulation of immune functions particularly in B cells, leading to abnormal lymphoproliferation or the production of autoantibodies that exacerbate inflammation and extrahepatic diseases. When considering the antiviral function of antibody, it was difficult to endorse its role in HCV protection, whereas T-cell response has been shown unequivocally critical for natural recovery. Recent breakthroughs in the study of HCV and antigen-specific antibody responses provide important insights into viral vulnerability to antibodies and the immunogenetic and structural properties of the neutralizing antibodies. The new knowledge reinvigorates HCV vaccine research by illuminating a new path for the rational design of vaccine antigens to elicit broadly neutralizing antibodies for protection.

Hepatitis C virus (HCV) diagnosis via microfluidics

Humans are subjected to various diseases; hence, proper diagnosis helps avoid further disease consequences. One such severe issue that could cause significant damage to the human liver is the hepatitis C virus (HCV). Several techniques are available to detect HCV under various categories, such as detection through antibodies, antigens, and RNA. Although immunoassays play a significant role in discovering hepatitis viruses, there is a need for point-of-care tests (POCT). Some developing strategies are required to ensure the appropriate selection of POCT for HCV detection, initiate appropriate antiviral therapy, and define associated risks, which will be critical in achieving optimal outcomes. Though molecular assays are precise, reproducible, sensitive, and specific, alternative strategies are required to enhance HCV diagnosis among the infected population. Herein, we described and assessed the potential of various microfluidic detection techniques and confirmatory approaches used in present communities. In addition, current key market players in HCV chip-based diagnosis and the future perspectives on the basis of which the diagnosis can be made easier are presented in the present review.

Sensitivity and specificity of rapid hepatitis C antibody assays in freshly collected whole blood, plasma and serum samples: A multicentre prospective study

Background

This study evaluated performance of two hepatitis C virus (HCV) rapid diagnostic tests (RDTs) performed by intended users in resource-limited settings.

Methods

Testing was conducted at three facilities in two countries (Georgia, Cambodia) using matched fingerstick whole blood, plasma and serum samples. Investigational RDTs were compared with a composite reference standard (CRS) comprised of three laboratory tests, and a reference RDT.

Results

In matched samples from 489 HCV positive and 967 HCV negative participants, specificity with both investigational RDTs was high using either reference method (≥98.4% in all sample types). Sensitivity was lower in whole blood versus plasma and serum for both RDTs compared with the CRS (86.5–91.4% vs 97.5–98.0% and 97.3–97.1%) and reference RDT (93.6–97.8% vs 100% and 99.4%). Sensitivity improved when considering only samples with detectable HCV viral load.

Conclusion

Sensitivity was highest in serum and plasma versus whole blood. The World Health Organization prequalification criterion (≥98%) was narrowly missed by both RDTs in serum, and one in plasma, possibly due to the intended user factor. Performance in whole blood was considered adequate, given potential roles of HCV infection history, improved sensitivity with detectable viral load and performance similarities to the reference RDT.

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.

Point-of-Care Tests for Hepatitis B Are Associated with A Higher Linkage to Care and Lower Cost Compared to Venepuncture Sampling During Outreach Screenings in an Asian Migrant Population

Background:

This study compares venepuncture versus point-of-care (POC) HBsAg tests on screening cost and linkage to care in prospective outreach screenings in an Asian population in three major cities in Belgium between 10/2014 and 5/2018.

Methods:

Two community outreach screening programs were organised between 10/2014 and 5/2018. The first screening program used venepuncture and serologic testing for HBsAg. In the second program, HBsAg was tested in finger stick blood POC tests. Positive results were confirmed during outpatient visits with serologic testing. Linkage to care was defined as having received specialist care follow-up with at least one abdominal ultrasound within three months of screening.

Results:

For 575 participating individuals, 571 valid results were obtained, 456 with venepuncture, and 115 using POC testing. Overall HBsAg seroprevalence was 6.8%. Linkage to care was higher when using POC testing compared to venepuncture (86% or n = 6/7 versus 34% or n = 11/32; p = 0.020). The POC screening program was economically more attractive with a total cost of € 1,461.8 or € 12.7 per person screened compared to € 24,819 or € 54.0 per person screened when using venepuncture testing. Results and an appointment for specialist care follow-up were given onsite with POC testing, while with venepuncture testing; results were sent within 20–45 days.

Conclusion:

In an Asian migrant population in Belgium with an HBsAg seroprevalence of 6.8%, HBV screening based on POC tests resulted in lower costs per person screened (76.5% lower), and higher linkage to care (2.5 times).

Evaluation of a new point-of-care oral anti-HCV test for screening of hepatitis C virus infection

BACKGROUND

Hepatitis C virus (HCV) infection is a public health issue for which an effective universal screening method is urgently needed. An oral anti-HCV test could provide a noninvasive and rapid screening strategy for HCV infection. This study evaluated the performance of a new point-of-care oral assay developed by Well for the detection of HCV antibody.

METHODS

Individuals from three centers with and without HCV infection were enrolled. All participants were tested for oral HCV antibody using the Well assay and for serum HCV antibody using established tests (ARCHITECT i2000 anti-HCV assay and InTec serum anti-HCV assay). For participants who obtained positive results, HCV RNA was tested for verification. Some patients underwent the OraQuick HCV test at the same time, and some self-tested with the Well assay during the same period.

RESULTS

A total of 1179 participants, including 486 patients with chronic HCV infection, 108 patients with other liver diseases, and 585 individuals who underwent physical examination, were enrolled. The Well anti-HCV test had a sensitivity of 91.88% (95% confidence interval [CI]: 88.97-94.09%) and a specificity of 98.00% (96.58-98.86%) for oral HCV antibody detection. The consistency between the Well and InTec assays was 97.02% (1138/1179). The consistency between the Well and OraQuick assays was 98.50% (197/200). Furthermore, the results of self-testing were highly consistent with those of researcher-administered tests (Kappa = 0.979). In addition, the HCV RNA results also showed that HCV RNA could only be detected on 1 of the 39 false-negative samples, and for 172 positive HCV RNA results, 171 could be detected by the Well oral anti-HCV assay.

CONCLUSIONS

The Well oral anti-HCV test offers high sensitivity and specificity and performed comparably to both the OraQuick assay and InTec assay for HCV diagnosis. Thus, the Well test represents a new tool for universal HCV screening to identify infected patients, particularly in regions with limited medical resources.

Sensitivity of hepatitis C virus rapid tests in detecting antibodies in general population

BACKGROUND

Evaluation of clinical performance of the anti-hepatitis C virus (HCV) rapid tests were carried out mostly in chronic hepatitis C patients and in individuals at high risk of HCV infection.

METHODS

The aim of this study was to evaluate the performance of OraQuick and Wantai rapid tests on archived serum samples from 1408 individuals (mean age 46, range 18-90; 65% female) recruited with a systematic sampling procedure during a general population survey.

RESULTS

The analysis of samples by Ortho HCV 3.0 ELISA and Cobas Taqman HCV RNA assays resulted in 69 anti-HCV antibody positive sera, including 42 HCV RNA positive (group 1) and 27 HCV RNA negative (group 2) samples. The performance of rapid tests was evaluated on the 69 anti-HCV positive (group 1+2) and 206 (OraQuick) and 198 (Wantai) anti-HCV negative sera, randomly selected from the 1339 anti-HCV negative samples. The OraQuick and Wantai rapid assays showed a sensitivity in group 1 of 92.9% and 90.5%, respectively. The sensitivity in group 2 was 40.7% and 51.9%, respectively. The anti-HCV antibodies signal/cutoff mean value was the only parameter that statistically differed between group 1 and group 2 individuals (P<0.0001). Further, 3 (OraQuick) and 4 samples (Wantai) from group 1, with very low HCV RNA level (<25 UI/mL), were misdiagnosed by rapid assays as false negative.

CONCLUSIONS

The proportion of infections with low level of viremia and the risk associated with rapid assay failure remained to be carefully estimated in general population.

Missed opportunities for diagnosing viral hepatitis C in Poland. Results from routine HCV testing at the Emergency Department in the Hospital for Infectious Diseases in Warsaw

AIM OF THE STUDY

Current statistics indicate that approximately 150,000 (0.5%) people in Poland suffer from active hepatitis C virus (HCV) infection, but only 20% among them are aware of their status. This project is based on the concept that screening based on the presence of HCV-related risks (a patient's individual history and behavioural risk factors) is more effective than obligatory testing of the whole population. This study investigates prevalence of serological markers for HCV among patients with a risk of exposure to HCV infection.

MATERIAL AND METHODS

The prospective study concerning patients of 18 years and older was conducted at the Emergency Department (ED) of the Hospital for Infectious Diseases in Warsaw (from 15 September 2016 until 23 July 2018). The inclusion criteria were: a blood transfusion before 1992, more than three hospitalizations in the lifetime, suspected liver disease, elevated aminotransferase activity, imprisonment, patient's own initiative, history of injecting drug use. The rapid HCV test was performed on all patients who fulfilled inclusion criteria. The statistical analyses included calculating serological positivity rate and comparing risk-group characteristics.

RESULTS

Among 1502 patients consulted at the emergency department with risk factors for HCV infection during the study period, the HCV test was performed in 1487 cases. New diagnoses were confirmed in 25 cases, HCV seroprevalence was 1.68%, all patients were linked to care, 21/25 (84.0%) were HCV RNA positive.

CONCLUSIONS

The study confirms that routine rapid testing in certain risk groups constitutes an essential tool for identifying new HCV infections and might have an important role for public health.

Approaches for simplified HCV diagnostic algorithms

Introduction

In the light of the advances in HCV antiviral therapy, global control of HCV infection becomes feasible but depends on the capacity of countries to identify infected people and to offer them treatment. To achieve the WHO goal which targets a diagnosis rate of 90% by 2030, simplification of screening and diagnosis will be crucial.

Methods

Published literature, unpublished data and expert consensus were used to determine key parameters, including point‐of‐care, rapid diagnostic testing, screening, the use of HCV core Ag and dried blood spots; starting from 2008 until November 2017. In addition, a manual search was undertaken to detect relevant papers or websites related to specific data from countries which underwent or are planning a programme of HCV elimination.

Results

Several strategies have been developed and evaluated these last years to simplify and facilitate access to screening and diagnosis, the development of reliable HCV core antigen tests and new nucleic acid amplification technologies for use in decentralized settings. In high prevalence settings, a one‐step screening and diagnosis strategy could simplify diagnostic algorithms provided the cost is reduced. Finally, genotyping may no longer be required in the context of availability of pangenotypic antiviral therapy.

Conclusions

Despite relevant advances in HCV screening and diagnosis, the overall diagnosis package is still too expensive today and efforts must be made to allow generalized implementation of reliable tests in low and middle income countries. These efforts will be key factors to foster a real public health approach to HCV elimination.

Comparative evaluation of three rapid immunochromatographic test assays with chemiluminescent microparticle immunoassay for the detection of hepatitis C virus antibody

Rapid diagnostic tests (RDTs) can serve as good alternatives to standard serological assays for hepatitis C virus (HCV) detection in limited resource settings. Aim of this study was to evaluate performance of three Indian manufactured RDTs with chemiluminescent microparticle immunoassay (CLIA) for screening of HCV infection with further evaluation using HCV RNA. Serum samples tested for anti-HCV by CLIA (Architect i1000SR, Abbott Diagnostics, IL, USA) were retrieved from - 80 °C and retested for anti-HCV by three RDTs: Alere Trueline (SD Bioline; Haryana, India) (RDT 1), Benesphera HCV Rapid card test (Avantor Performance Materials India Limited; Uttarakhand, India) (RDT 2), AccuTest HCV (Accurex Biomedical Pvt. Ltd.; Mumbai, India) (RDT 3). HCV RNA results were obtained from hospital information system and anti-HCV reactive but RNA negative cases without treatment were considered as either 'false positives' or 'spontaneous clearance of HCV RNA'. Among 86 samples, 75 (87.2%), 49 (57%), 58 (67.4%) and 51 (59.3%) were reactive by CLIA, RDT1, RDT2 and RDT3, respectively. Taking CLIA as reference standard, RDT 1, 2 and 3 demonstrated sensitivity of 65.30%, 77.33% and 68% respectively. Specificity of all three RDTs was 100% with sensitivity of 97.6-100% above signal/cut-off ratio (S/Co) of 6 by CLIA and 88-100% in all HCV RNA positive cases. Sensitivity of RDTs increased from 65.30-77.33 to 72-82.4% when RNA negative/anti-HCV reactive results were considered as non-reactive. The three RDTs have acceptable sensitivity and specificity in anti-HCV detection especially in RNA positive patients that would require treatment for HCV.

A novel point-of-care oral anti-HCV assay: Is it reliable for screening hepatitis C virus infection in the era of direct-acting antivirals?

Recent advance in the direct-acting antivirals (DAAs) offers the potentials to eradicate hepatitis C virus (HCV) worldwide and makes universal screening more urgent. A point-of-care (POC) oral anti-HCV assay, the Fortune assay, was developed and its performance was evaluated. Individuals with or without HCV infection were recruited in three Centers. Paired oral and serum samples were tested using the Fortune and InTec anti-HCV assays. The Kehua serum anti-HCV assay served as a supplemental test to verify the discordant results. Some oral samples were also tested using the OraQuick anti-HCV assay. Furthermore, the Fortune assay results were compared with the documented RNA results. Sensitivity, specificity, and accuracy of the Fortune assay was 93.11%, 98.48%, and 96.58%, respectively (n = 1,022). Consistency between the Fortune and OraQuick assays was 96.35% (264/274); the Fortune assay detected additional 8 positive oral samples missed by the OraQuick assay. The Fortune assay demonstrated a 97.46% (115/118) positivity among the viremic patients. Furthermore, its sensitivity was HCV genotype independent. In conclusion, the Fortune assay was highly specific and accurate. It had comparable sensitivity as the serum assays for the diagnosis of active HCV infection. It provides a completely non-invasive and reliable tool for HCV screening in the DAA era.

The risks of HCV infection among Brazilian crack cocaine users: incorporating diagnostic test uncertainty

Despite the initiative by WHO and other international organizations to eliminate HCV in the medium term, hepatitis C infection is still a major public health problem. Even non-injecting drugs users who engage in harmful or addictive drug use are at greater risk of acquiring the infection, when compared to the general population. This study evaluate risk factors for HCV infection in users of crack/cocaine in Brazil, using multilevel models that incorporate variations in the sensitivity and specificity of the respective diagnostic tests. The sample included all the participants of a national survey on street crack cocaine users with serologically reactive result in the rapid test for the HCV as well as 4 non-reactive controls, matched by sex, age category, and major geographic region of residence. Multilevel logistic regression models were used, with and without incorporation of the diagnostic test’s sensitivity and specificity values. The odds of HCV infection were 85% higher among polydrug users, 7.81 times higher among injecting drug users, and 3.69 times higher in those reporting to have genital ulcers. Statistical modeling strategies that incorporate the sensitivity and specificity of diagnostic tests in challenging settings are useful for studying the association between risk factors and infection status.

Accuracy of rapid test for diagnosis of hepatitis A with different infection rate settings and with predictive modeling

AIM

We evaluated the accuracy of a commercial rapid immunochromatographic test (rapid test [RT]) for hepatitis A (HA) diagnosis and epidemiological studies.

MATERIALS & METHODS

The accuracy of a RT was evaluated in laboratory and in field conditions. Predictive modeling estimated the test performance in a hypothetical population.

RESULTS

The RT showed sensitivities of 66-86%, and specificities of 21-100%, depending on the antibody isotype (IgM or IgG) analyzed and prevalence of infection.

CONCLUSION

The RT is a good alternative for diagnostic in HA outbreaks. The predictive model indicates that it should not be used alone for HA diagnosis in low prevalence populations. These data can be used in the future to strengthen decision-making during the implementation of rapid diagnostic methods in health services.

New virological tools for screening, diagnosis and monitoring of hepatitis B and C in resource-limited settings

Worldwide, the increasingly dominant model of laboratory testing is the centralised laboratory, in which automation of analytical processes increases, enabling the analysis of large numbers of samples at a relatively low cost. However, this trend does not fulfil the requirements for care of patients with chronic hepatitis B and C in resource-limited settings. Alternative models using point-of-care (POC) tests and dried blood spots (DBSs) are increasingly being considered for viral hepatitis screening, diagnosis and monitoring. POC tests are small devices providing qualitative and/or quantitative determination of viral antibodies and/or antigens. They can use original specimen matrices, such as oral fluid or blood collected from a fingerstick. POC tests are particularly useful for large-scale screening, and to improve access to care in regions where laboratory access is limited. New POC devices that detect and quantify viral nucleic acids are at the developmental stage. DBSs offer the main advantage of enabling storage of desiccated blood that can be easily transported to reference centres, where state-of-the-art molecular and serological diagnostic tests are available. However, standardisation and better automation of DBS handling are needed. Herein, we review alternatives to classical hepatitis B and C virological tests, examining POC tests and DBSs, as well as alternatives to nucleic acid testing. Innovations in testing approaches resulting from the availability of these new assays are also discussed.

Performance of point of care assays for hepatitis B and C viruses in chronic kidney disease patients

AIMS

Point of care testing (POCT) has been used for hepatitis B and C diagnosis in general population, but little is known about the influence of clinical conditions in the accuracy of these assays. This study aims to evaluate the performance of POCTs for detection of hepatitis B virus surface antigen (HBsAg) and antibodies to Hepatitis C Virus (anti-HCV) in Chronic Kidney Disease (CKD) patients.

METHODS

A total of 286 subjects were included in this study. HBsAg and anti-HCV were detected using commercial EIAs and four POCTs: HBsAg (WAMA Imuno-Rápido HBsAg and VIKIA HBsAg) and anti-HCV (DOLES HCV teste rápido and WAMA Imuno-Rápido anti-HCV) in serum and whole blood.

RESULTS

Using EIA, HBsAg and anti-HCV prevalence was 4.5% and 16.1% in CKD patients. HBsAg and anti-HCV POCTs had sensitivities from 92.3% to 100% and 84.8% to 89.1% while specificities were 99.3% to 100% and 99.2% to 99.6%, respectively. POCT using serum samples performed well compared with whole blood samples and true positive samples of POCTs had high optical density to cut-off (OD/CO) values compared with EIA.

CONCLUSIONS

This study demonstrates good performance of HBsAg and anti-HCV POCTs in CKD patients, especially in serum samples indicating low interference of this disease in the performance of these assays. POCTs could be an important tool for HBV and HCV screening in high-risk populations.

Diagnostic accuracy of tests to detect Hepatitis C antibody: a meta-analysis and review of the literature

BACKGROUND

Although direct-acting antivirals can achieve sustained virological response rates greater than 90% in Hepatitis C Virus (HCV) infected persons, at present the majority of HCV-infected individuals remain undiagnosed and therefore untreated. While there are a wide range of HCV serological tests available, there is a lack of formal assessment of their diagnostic performance. We undertook a systematic review and meta-analysis to evaluate he diagnostic accuracy of available rapid diagnostic tests (RDT) and laboratory based EIA assays in detecting antibodies to HCV.

METHODS

We used the PRISMA checklist and Cochrane guidance to develop our search protocol. The search strategy was registered in PROSPERO (CRD42015023567). The search focused on hepatitis C, diagnostic tests, and diagnostic accuracy within eight databases (MEDLINE, EMBASE, the Cochrane Central Register of Controlled Trials, Science Citation Index Expanded, Conference Proceedings Citation Index-Science, SCOPUS, Literatura Latino-Americana e do Caribe em Ciências da Saúde and WHO Global Index Medicus. Studies were included if they evaluated an assay to determine the sensitivity and specificity of HCV antibody (HCV Ab) in humans. Two reviewers independently extracted data and performed a quality assessment of the studies using the QUADAS tool. We pooled test estimates using the DerSimonian-Laird method, by using the software R and RevMan. 5.3.

RESULTS

A total of 52 studies were identified that included 52,673 unique test measurements. Based on five studies, the pooled sensitivity and specificity of HCV Ab rapid diagnostic tests (RDTs) were 98% (95% CI 98-100%) and 100% (95% CI 100-100%) compared to an enzyme immunoassay (EIA) reference standard. High HCV Ab RDTs sensitivity and specificity were observed across screening populations (general population, high risk populations, and hospital patients) using different reference standards (EIA, nucleic acid testing, immunoblot). There were insufficient studies to undertake subanalyses based on HIV co-infection. Oral HCV Ab RDTs also had excellent sensitivity and specificity compared to blood reference tests, respectively at 94% (95% CI 93-96%) and 100% (95% CI 100-100%). Among studies that assessed individual oral RDTs, the eight studies revealed that OraQuick ADVANCE® had a slightly higher sensitivity (98%, 95% CI 97-98%) compared to the other oral brands (pooled sensitivity: 88%, 95% CI 84-92%).

CONCLUSIONS

RDTs, including oral tests, have excellent sensitivity and specificity compared to laboratory-based methods for HCV antibody detection across a wide range of settings. Oral HCV Ab RDTs had good sensitivity and specificity compared to blood reference standards.

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 and C virus infection among alcoholic individuals: importance of screening and vaccination

Drug users have been reported to have an increased risk for acquisition of viral hepatitis. This study aims to evaluate the prevalence of HBV and HCV infection and usefulness of saliva for HBsAg and anti-HCV detection in alcoholic patients.A total of 90 alcoholic patients were recruited in 2013. HBsAg and anti-HCV were tested in serum and saliva, anti-HBc and anti-HBs were tested in serum using commercial enzyme immunoassays (EIA).Using serum samples, anti-HCV, HBsAg, anti-HBc and anti-HBs prevalences were 5.6%, 0%, 15.7%, and 29.2%. HBsAg detection in saliva showed 100% of specificity and anti-HCV detection demonstrated 100% of sensitivity and 94.7% of specificity. Low prevalence of HBV and high prevalence of anti-HCV were found and reinforced the recommendation of HBV vaccination to avoid the acute and chronic cases and HCV screening in this group to identify cases for antiviral therapy. Saliva samples could be used for anti-HCV detection in this population, what could increase the diagnosis access.

State of the Art, Unresolved Issues, and Future Research Directions in the Fight against Hepatitis C Virus: Perspectives for Screening, Diagnostics of Resistances, and Immunization

Hepatitis C virus (HCV) still represents a major public health threat, with a dramatic burden from both epidemiological and clinical points of view. New generation of direct-acting antiviral agents (DAAs) has been recently introduced in clinical practice promising to cure HCV and to overcome the issues related to the interferon-based therapies. However, the emergence of drug resistance and the suboptimal activity of DAAs therapies against diverse HCV genotypes have been observed, determining treatment failure and hampering an effective control of HCV spread worldwide. Moreover, these treatments remain poorly accessible, particularly in low-income countries. Finally, effective screening strategy is crucial to early identifying and treating all HCV chronically infected patients. For all these reasons, even though new drugs may contribute to impacting HCV spread worldwide a preventive HCV vaccine remains a cornerstone in the road to significantly reduce the HCV spread globally, with the ultimate goal of its eradication. Advances in molecular vaccinology, together with a strong financial, political, and societal support, will enable reaching this fundamental success in the coming years. In this comprehensive review, the state of the art about these major topics in the fight against HCV and the future of research in these fields are discussed.

Who to test and how to test for chronic hepatitis C infection - 2016 WHO testing guidance for low- and middle-income countries

Testing and diagnosis of hepatitis C virus (HCV) infection is the gateway for access to both treatment and prevention services, and crucial for an effective hepatitis epidemic response. In contrast to HIV, a systematic approach to hepatitis C testing has been fragmented and limited to a few countries, and there remains a large burden of undiagnosed cases globally. Key challenges in the current hepatitis testing response, include lack of simple, reliable, and low cost diagnostic tests, laboratory capacity, and testing facilities; inadequate data to guide country-specific hepatitis testing approaches and who to test; stigmatization and social marginalization of some groups with or at risk of viral hepatitis; and lack of international or national guidelines on hepatitis testing for resource-limited settings. New tools to support the hepatitis global response include the 2016 Global Hepatitis Health Sector Strategy which include targets for testing and diagnosis, and World Health Organization (WHO) 2016 hepatitis testing guidelines for adults, adolescents, and children in low- and middle-income countries. The testing guidance complements recent published WHO guidance on the prevention, care and treatment of chronic hepatitis C and hepatitis B infection. These testing guidelines outline the public health approach to strengthening and expanding current testing practices for HCV and HBV and address what serological and virological assays to use, and who to test, as well as interventions to promote linkage to prevention and care after testing. They are intended for use across all age groups and populations. See boxes for key recommendations. Future directions and innovations in viral hepatitis testing include use of point-of-care assays for nucleic acid testing (NAT) and core antigen; validation of dried blood spots specimens with different commercial serological and NAT assays; multiplex and polyvalent platforms for integrated testing of HIV, HBV and HCV; and potential for self-testing.

A pilot study of rapid hepatitis C virus testing in the Rhode Island Department of Corrections

BACKGROUND

The correctional population bears a heavy burden of hepatitis C virus (HCV) infection necessitating expansion of HCV testing and treatment opportunities. Rapid HCV testing provides point-of-care antibody results and may be ideal for correctional facilities, particularly jails, where persons are often incarcerated for short periods of time, yet feasibility has not been established.

METHODS

We conducted a pilot study of a rapid HCV testing algorithm among short-term inmates with unknown HCV status. Participants completed a questionnaire, viewed an informational video and underwent rapid HCV testing and confirmatory testing, when indicated. Persons with chronic infection were referred to community care after release. Baseline characteristics, risk behaviors, test results and linkage were examined by descriptive analyses.

RESULTS

Two hundred and fifty-two inmates were enrolled and 249 completed all study activities. Twenty-five participants (10%) had reactive rapid tests and 23 (92%) completed confirmatory testing. 15/23 (65%) had detectable HCV RNA, but only 4 linked to care after release. Persons with reactive HCV tests were more likely to be White (P = 0.01) and to have ever injected (P < 0.0001) and/or recently injected (P < 0.0001) drugs.

CONCLUSIONS

Rapid HCV testing within jails is feasible, identifies previously unrecognized cases of HCV infection, and implementation should be considered. Low rates of linkage to care after release remain a barrier to care.

Evaluating HBsAg rapid test performance for different biological samples from low and high infection rate settings & populations

Background

Rapid tests (RTs) might have several advantages over standard laboratory procedures, increasing access to diagnosis, especially among vulnerable populations and/or those living in remote areas. The aim of this study was to evaluate the performance of RTs for the detection of hepatitis B virus surface antigen (HBsAg) in samples from different populations/settings.

Methods

Three RTs for HBsAg detection (Vikia® HBsAg, HBsAg Teste Rápido®, and Imuno-Rápido HBsAg®) and different biological specimens (serum, whole blood, and saliva) were evaluated. Analyses comprised a reference panel and samples from field studies targeting suspected cases of hepatitis B virus (HBV) (G I), individuals living in deprived areas (G II), and highly vulnerable individuals (G III). Enzyme immunoassay (EIA) was defined as the gold standard in this study. Reproducibility, repeatability, and cross-reactivity with other infectious agents such as dengue, immunodeficiency (HIV), and hepatitis C (HCV) viruses and T. pallidum were determined.

Results

For the reference panel, the sensitivity and specificity of all HBsAg RTs were higher than 93.00 %. G I presented the highest kappa values for all rapid assays using sera samples. When using serum, the sensitivity values were higher than 93.40 for G I, 60.00 % for G II and 66.77 % for G III, and the specificity values were higher than 99.50 for GI, 97.20 for G II and 99.10 % for G III for all tests. For whole blood samples & the Vikia® HBsAg assay, the best performance was achieved for GIII (k = 79.75 %). For saliva samples, the Imuno-Rápido HBsAg® assay showed the highest concordance values with EIA for G I (40.68 %) and G II (32.20 %). The reproducibility and repeatability of all RTs for serum and saliva were excellent, and the concordance between HBsAg EIAs and RTs using samples reactive with other infectious agents varied from 70.10 % to 100.00 %.

Conclusions

The overall performance of RTs for HBsAg in serum was high/moderately high for all groups, thereby promoting increased access to HBV diagnosis among vulnerable populations as well as samples from individuals in emergency settings or remote areas. Rapid tests for HBsAg using whole blood could be used in prevalence studies, though these assays should not be used for saliva samples.

Electronic supplementary material

The online version of this article (doi:10.1186/s12879-015-1249-5) contains supplementary material, which is available to authorized users.

Update on hepatitis B and C virus diagnosis

Viral hepatitis B and C virus (HBV and HCV) are responsible for the most of chronic liver disease worldwide and are transmitted by parenteral route, sexual and vertical transmission. One important measure to reduce the burden of these infections is the diagnosis of acute and chronic cases of HBV and HCV. In order to provide an effective diagnosis and monitoring of antiviral treatment, it is important to choose sensitive, rapid, inexpensive, and robust analytical methods. Primary diagnosis of HBV and HCV infection is made by using serological tests for detecting antigens and antibodies against these viruses. In order to confirm primary diagnosis, to quantify viral load, to determine genotypes and resistance mutants for antiviral treatment, qualitative and quantitative molecular tests are used. In this manuscript, we review the current serological and molecular methods for the diagnosis of hepatitis B and C.

Hepatitis C Virus Treatment: Is It Possible To Cure All Hepatitis C Virus Patients?

The recent advances in hepatitis C virus (HCV) therapeutics have brought combinations of direct acting antiviral medications that offer interferon-free, well-tolerated regimens with sustained virologic response rates greater than 90% in clinical trials for many patient groups. The successes have prompted discussions regarding cure for all patients. These regimens have already demonstrated the ability to cure previously challenging patient groups, including human immunodeficiency virus-HCV coinfection, decompensated cirrhosis, and post-liver transplantation. Limitations exist in the current portfolio of agents, with suboptimal outcomes for genotype 3 and limited data in genotypes 5 and 6. More data are urgently needed in patients with chronic kidney disease and in children. With ongoing developments, highly effective regimens for all these patient groups are within reach. To deliver HCV treatment throughout the world and particularly in low- and middle-income countries, regimens need to be affordable but also pan-genotypic, well-tolerated, and delivered once daily for 4-8 weeks. With such a regimen, cure for all patients would then hinge on the ability to identify patients with HCV infection and deliver treatment within their communities. This review will discuss the strategies that will be necessary to realize this opportunity to cure all persons with HCV infection.

Hepatitis C virus: Virology, diagnosis and treatment

More than twenty years of study has provided a better understanding of hepatitis C virus (HCV) life cycle, including the general properties of viral RNA and proteins. This effort facilitates the development of sensitive diagnostic tools and effective antiviral treatments. At present, serologic screening test is recommended to perform on individuals in the high risk groups and nucleic acid tests are recommended to confirm the active HCV infections. Quantization and genotyping of HCV RNAs are important to determine the optimal duration of anti-viral therapy and predict the likelihood of response. In the early 2000s, pegylated interferon plus ribavirin became the standard anti-HCV treatment. However, this therapy is not ideal. To 2014, boceprevir, telaprevir, simeprevir, sofosbuvir and Harvoni are approved by Food and Drug Administration for the treat of HCV infections. It is likely that the new all-oral, interferon-free, pan-genotyping anti-HCV therapy will be available within the next few years. Majority of HCV infections will be cured by these anti-viral treatments. However, not all patients are expected to be cured due to viral resistance and the high cost of antiviral treatments. Thus, an efficient prophylactic vaccine will be the next challenge in the fight against HCV infection.