Addressing Failures in Achieving Hypertension Control in Low- and Middle-Income Settings through Simplified Treatment Algorithms.

Hypertension is the most important risk factor for cardiovascular diseases (CVDs), which are the leading global cause of death. Hypertension is under-diagnosed and under-treated in most low- and middle-income countries (LMICs). Current algorithms for hypertension treatment are complex for the healthcare worker, limit decentralization, complicate procurement and often translate to a large pill burden for the person with hypertension. We summarize evidence supporting implementation of simple, algorithmic, accessible, non-toxic and effective (SAANE) algorithms to provide a feasible way to access and maintain quality care for hypertension. Implementation of these algorithms will enable task shifting to less specialised health care workers and lay cadres, provision of fixed dose combinations, consolidation of the market while retaining generic competition, simplification of laboratory requirements, and lowering costs for health systems and people who incur out of pocket expenses.

Turning threats into opportunities: how to implement and advance quality TB services for people with HIV during the COVID-19 pandemic and beyond.

INTRODUCTION: Until COVID-19, tuberculosis (TB) was the leading infectious disease killer globally, disproportionally affecting people with HIV. The COVID-19 pandemic is threatening the gains made in the fight against both diseases. DISCUSSION: Although crucial guidance has been released on how to maintain TB and HIV services during the pandemic, it is acknowledged that what was considered normal service pre-pandemic needs to improve to ensure that we rebuild person-centred, inclusive and quality healthcare services. The threat that the pandemic may reverse gains in the response to TB and HIV may be turned into an opportunity by pivoting to using proven differentiated service delivery approaches and innovative technologies that can be used to maintain care during the pandemic and accelerate improved service delivery in the long term. Models of care should be convenient, supportive and sufficiently differentiated to avoid burdensome clinic visits for medication pick-ups or directly observed treatments. Additionally, the pandemic has highlighted the chronic and short-sighted lack of investment in health systems and the need to prioritize research and development to close the gaps in TB diagnosis, treatment and prevention, especially for children and people with HIV. Most importantly, TB-affected communities and civil society must be supported to lead the planning, implementation and monitoring of TB and HIV services, especially in the time of COVID-19 where services have been disrupted, and to report on legal, policy and gender-related barriers to access experienced by affected people. This will help to ensure that TB services are held accountable by affected communities for delivering equitable access to quality, affordable and non-discriminatory services during and beyond the pandemic. CONCLUSIONS: Successfully reaching the related targets of ending TB and AIDS as public health threats by 2030 requires rebuilding of stronger, more inclusive health systems by advancing equitable access to quality TB services, including for people with HIV, both during and after the COVID-19 pandemic. Moreover, services must be rights-based, community-led and community-based, to ensure that no one is left behind.

Framework for the implementation of advanced HIV disease diagnostics in sub-Saharan Africa: programmatic perspectives.

Patients with advanced HIV disease have a high risk of mortality, mainly from tuberculosis and cryptococcal meningitis. The advanced HIV disease management package recommended by WHO, which includes diagnostics, therapeutics, and patient psychosocial support, is barely implemented in many different countries. Here, we present a framework for the implementation of advanced HIV disease diagnostics. Laboratory and point-of-care-based reflex testing, coupled with provider-initiated requested testing, for cryptococcal antigen and urinary Mycobacterium tuberculosis lipoarabinomannan antigen, should be done for all patients with CD4+ cell counts of 200 cells per µL or less. Implementation of the advanced HIV disease package should be encouraged within primary health-care facilities and task shifting of testing to lay cadres could facilitate access to rapid results. Implementation of differentiated antiretroviral therapy delivery models can allow clinicians enough time to focus on the management of patients with advanced HIV disease. Efficient up-referral and post-discharge systems, including the development of patient-centric advanced HIV disease literacy, are also crucial. Implementation of the advanced HIV disease package is feasible at all health-care levels, and it should be part of the core of the global response towards ending AIDS as a public health threat.

Let's talk chronic disease: can differentiated service delivery address the syndemics of HIV, hypertension and diabetes?

PURPOSE OF REVIEW: Differentiated service delivery (DSD) for HIV provides an approach to scaling services that are client-centred and aims to address client challenges whilst reducing the burden on health systems. With access to antiretroviral therapy, people living with HIV are living longer and increasingly present with comorbid conditions, such as hypertension and diabetes. This review presents the syndemic burden of HIV, hypertension and diabetes and highlights opportunities and challenges to leveraging DSD across diseases. RECENT FINDINGS: Prevalence of hypertension and diabetes in the eight highest HIV prevalence countries ranges between 20-24% (31.9% in those >50 years old) and 4-10%, respectively. Service delivery models addressing the concurrent syndemics focus primarily on integration of services. Two DSD examples were found where people living with HIV and other comorbidities had their care and treatment supported in healthcare worker-led facility-based adherence clubs. SUMMARY: Key enablers that have supported DSD for HIV such as simplified algorithms, optimized formulations, secure drug supply, and strengthened monitoring and evaluation systems are lacking for hypertension and diabetes and thus pose a major challenge to leveraging DSD models for people with syndemic conditions. However, the DSD approach may also catalyse opportunities to provide person-centred care for these syndemics and more implementation research in this area is warranted.

Prioritising pathogens for the management of severe febrile patients to improve clinical care in low- and middle-income countries.

BACKGROUND: Severe febrile illness without a known source (SFWS) is a challenge for clinicians when deciding how to manage a patient, particularly given the wide spectrum of potential aetiologies that contribute to fever. These infections are difficult to distinguish clinically, and accurate diagnosis requires a plethora of diagnostics including blood cultures, imaging techniques, molecular or serological tests, and more. When laboratory services are available, a limited test menu hinders clinical decision-making and antimicrobial stewardship, leading to empiric treatment and suboptimal patient outcomes. To specifically address SFWS, this work aimed to identify priority pathogens for a globally applicable panel for fever causing pathogens. METHOD: A pragmatic two-pronged approach combining currently available scientific data in an analytical hierarchy process and systematically gathered expert input, was designed to address the lack of comprehensive global aetiology data. The expert re-ranked list was then further adapted for a specific use case to focus on community acquired infections in whole blood specimens. The resulting list was further analysed to address different geographical regions (Asia, Africa, and Latin America), and Cohen kappa scores of agreement were calculated. RESULTS: The expert ranked prioritized pathogen list generated as part of this two-pronged approach included typhoidal Salmonella, Plasmodium species and Mycobacterium tuberculosis as the top 3 pathogens. This pathogen list was then further adapted for the SFWS use case to develop a final pathogen list to inform product development. Subsequent analysis comparing the relevance of the SFWS pathogen list to multiple populations and geographical regions showed that the SFWS prioritized list had considerable utility across Africa and Asia, but less so for Latin America. In addition, the list showed high levels of agreement across different patient sub-populations, but lower relevance for neonates and symptomatic HIV patients. CONCLUSION: This work highlighted once again the challenges of prioritising in global health, but it also shows that taking a two-pronged approach, combining available prevalence data with expert input, can result in a broadly applicable priority list. This comprehensive utility is particularly important in the context of product development, where a sufficient market size is essential to achieve a sustainable commercialized diagnostic product to address SFWS.

Quantifying the incidence of severe-febrile-illness hospital admissions in sub-Saharan Africa.

Severe-febrile-illness (SFI) is a common cause of morbidity and mortality across sub-Saharan Africa (SSA). The burden of SFI in SSA is currently unknown and its estimation is fraught with challenges. This is due to a lack of diagnostic capacity for SFI in SSA, and thus a dearth of baseline data on the underlying etiology of SFI cases and scant SFI-specific causative-agent prevalence data. To highlight the public health significance of SFI in SSA, we developed a Bayesian model to quantify the incidence of SFI hospital admissions in SSA. Our estimates indicate a mean population-weighted SFI-inpatient-admission incidence rate of 18.4 (6.8-31.1, 68% CrI) per 1000 people for the year 2014, across all ages within areas of SSA with stable Plasmodium falciparum transmission. We further estimated a total of 16,200,337 (5,993,249-27,321,779, 68% CrI) SFI hospital admissions. This analysis reveals the significant burden of SFI in hospitals in SSA, but also highlights the paucity of pathogen-specific prevalence and incidence data for SFI in SSA. Future improvements in pathogen-specific diagnostics for causative agents of SFI will increase the abundance of SFI-specific prevalence and incidence data, aid future estimations of SFI burden, and enable clinicians to identify SFI-specific pathogens, administer appropriate treatment and management, and facilitate appropriate antibiotic use.

Accelerating the elimination of viral hepatitis: a Lancet Gastroenterology & Hepatology Commission.

Viral hepatitis is a major public health threat and a leading cause of death worldwide. Annual mortality from viral hepatitis is similar to that of other major infectious diseases such as HIV and tuberculosis. Highly effective prevention measures and treatments have made the global elimination of viral hepatitis a realistic goal, endorsed by all WHO member states. Ambitious targets call for a global reduction in hepatitis-related mortality of 65% and a 90% reduction in new infections by 2030. This Commission draws together a wide range of expertise to appraise the current global situation and to identify priorities globally, regionally, and nationally needed to accelerate progress. We identify 20 heavily burdened countries that account for over 75% of the global burden of viral hepatitis. Key recommendations include a greater focus on national progress towards elimination with support given, if necessary, through innovative financing measures to ensure elimination programmes are fully funded by 2020. In addition to further measures to improve access to vaccination and treatment, greater attention needs to be paid to access to affordable, high-quality diagnostics if testing is to reach the levels needed to achieve elimination goals. Simplified, decentralised models of care removing requirements for specialised prescribing will be required to reach those in need, together with sustained efforts to tackle stigma and discrimination. We identify key examples of the progress that has already been made in many countries throughout the world, demonstrating that sustained and coordinated efforts can be successful in achieving the WHO elimination goals.

Survey of programmatic experiences and challenges in delivery of hepatitis B and C testing in low- and middle-income countries.

BACKGROUND: There have been few reports on programmatic experience of viral hepatitis testing and treatment in resource-limited settings. To inform the development of the 2017 World Health Organization (WHO) viral hepatitis testing guidance and in particular the feasibility of proposed recommendations, we undertook a survey across a range of organisations engaged with hepatitis testing in low- and middle-income countries (LMICs). Our objective was to describe current hepatitis B and C testing practices across a range of settings in different countries, as well as key barriers or challenges encountered and proposed solutions to promote testing scale-up. METHODS: Hepatitis testing programmes in predominantly LMICs were identified from the WHO Global Hepatitis Programme contacts database and through WHO regional offices, and invited to participate. The survey comprised a six-part structured questionnaire: general programme information, description of hepatitis testing, treatment and care services, budget and funding, data on programme outcomes, and perceptions on key barriers encountered and strategies to address these. RESULTS: We interviewed 22 viral hepatitis testing programmes from 19 different countries. Nine were from the African region; 6 from the Western Pacific; 4 from South-East Asia; and 3 from Eastern Europe. All but four of the programmes were based in LMICs, and 10 (45.5%) were supported by non-governmental or international organizations. All but two programmes undertook targeted testing of specific affected populations such as people living with HIV, people who inject drugs, sex workers, health care workers, and pregnant women. Only two programmes focussed on routine testing in the general population. The majority of programmes were testing in hospital-based or other health facilities, particularly HIV clinics, and community-based testing was limited. Nucleic acid testing (NAT) for confirmation of HCV and HBV viraemia was available in only 30% and 18% of programmes, respectively. Around a third of programmes required some patient co-payment for diagnosis. The most commonly identified challenges in scale-up of hepatitis testing were: limited community awareness about viral hepatitis; lack of facilities or services for hepatitis testing; no access to low cost treatment, particularly for HCV; absence of national guidance and policies; no dedicated budget for hepatitis; and lack of trained health care and laboratory workers. CONCLUSIONS: At this early stage in the global scale-up of testing for viral hepatitis, there is a wide variation in testing practices and approaches across different programmes. There remains limited access to NAT to confirm viraemia, and patient self-payment for testing and treatment is common. There was consensus from implementing organizations that scale-up of testing will require increased community awareness, health care worker training, development of national strategies and guidelines, and improved access to low cost NAT virological testing.

Values, preferences and current hepatitis B and C testing practices in low- and middle-income countries: results of a survey of end users and implementers.

BACKGROUND: Access to hepatitis B virus (HBV) and hepatitis C virus (HCV) diagnostics remains a key bottleneck in scale-up of access to HBV and HCV treatment, particularly in low- and middle-income countries (LMICs) that lack laboratory resources and skilled personnel. To inform the development of World Health Organization (WHO) testing guidelines on who to test and how to test, we performed a "values and preferences" survey of end users and implementers of hepatitis testing in LMICs on current hepatitis B and C testing practices and acceptability of diagnostic approaches, as well as preferences for the future. METHODS: The survey consisted of a four-part, 28 question online survey tool using SurveyMonkey software. The invitation to participate was sent via email to a network of contacts in hepatitis clinical care, research, advocacy and industry. RESULTS: The survey collected responses on current testing practices from 48 respondents in 23 LMICs. Only a small proportion of hepatitis testing is currently funded through government-supported programmes. Most limit their testing programmes to blood donor screening and although testing is recommended in several populations, this is not well implemented. Also, there is still very limited access to virological testing. CONCLUSIONS: The survey showed that HBV and HCV testing programmes in LMICs are inadequate and/or scarce. Lack of affordable diagnostic tests; lack of funding, public education and awareness; absence of national policies and guidelines; and a dearth of skilled health professionals are the most important barriers to scaling up HBV and HCV diagnosis and treatment.

Diagnostic accuracy of detection and quantification of HBV-DNA and HCV-RNA using dried blood spot (DBS) samples - a systematic review and meta-analysis.

BACKGROUND: The detection and quantification of hepatitis B (HBV) DNA and hepatitis C (HCV) RNA in whole blood collected on dried blood spots (DBS) may facilitate access to diagnosis and treatment of HBV and HCV infection in resource-poor settings. We evaluated the diagnostic performance of DBS compared to venous blood samples for detection and quantification of HBV-DNA and HCV-RNA in two systematic reviews and meta-analyses on the diagnostic accuracy of HBV DNA and HCV RNA from DBS compared to venous blood samples. METHODS: We searched MEDLINE, Embase, Global Health, Web of Science, LILAC and Cochrane library for studies that assessed diagnostic accuracy with DBS. Heterogeneity was assessed and where appropriate pooled estimates of sensitivity and specificity were generated using bivariate analyses with maximum likelihood estimates and 95% confidence intervals. We also conducted a narrative review on the impact of varying storage conditions or different cut-offs for detection from studies that undertook this in a subset of samples. The QUADAS-2 tool was used to assess risk of bias. RESULTS: In the quantitative synthesis for diagnostic accuracy of HBV-DNA using DBS, 521 citations were identified, and 12 studies met the inclusion criteria. Overall quality of studies was rated as low. The pooled estimate of sensitivity and specificity for HBV-DNA was 95% (95% CI: 83-99) and 99% (95% CI: 53-100), respectively. In the two studies that reported on cut-offs and limit of detection (LoD) - one reported a sensitivity of 98% for a cut-off of ≥2000 IU/ml and another reported a LoD of 914 IU/ml using a commercial assay. Varying storage conditions for individual samples did not result in a significant variation of results. In the synthesis for diagnostic accuracy of HCV-RNA using DBS, 15 studies met the inclusion criteria, and this included six additional studies to a previously published review. The pooled sensitivity and specificity was 98% (95% CI:95-99) and 98% (95% CI:95-99.0), respectively. Varying storage conditions resulted in a decrease in accuracy for quantification but not for reported positivity. CONCLUSIONS: These findings show a high level of diagnostic performance for the use of DBS for HBV-DNA and HCV-RNA detection. However, this was based on a limited number and quality of studies. There is a need for development of standardized protocols by manufacturers on the use of DBS with their assays, as well as for larger studies on use of DBS conducted in different settings and with varying storage conditions.

Optimising diagnosis of viraemic hepatitis C infection: the development of a target product profile.

BACKGROUND: The current low access to virological testing to confirm chronic viraemic HCV infection in low- and middle-income countries (LMIC) is limiting the rollout of hepatitis C (HCV) care. Existing tests are complex, costly and require sophisticated laboratory infrastructure. Diagnostic manufacturers need guidance on the optimal characteristics a virological test needs to have to ensure the greatest impact on HCV diagnosis and treatment in LMIC. Our objective was to develop a target product profile (TPP) for diagnosis of HCV viraemia using a global stakeholder consensus-based approach. METHODS: Based on the standardised process established to develop consensus-based TPPs, we followed five key steps. (i) Identifying key potential global stakeholders for consultation and input into the TPP development process. (ii) Informal priority-setting exercise with key experts to identify the needs that should be the highest priority for the TPP development; (iii) Defining the key TPP domains (scope, performance and operational characteristics and price). (iv) Delphi-like process with larger group of key stakeholder to facilitate feedback on the key TPP criteria and consensus building based on pre-defined consensus criteria. (v) A final consensus-gathering meeting for discussions around disputed criteria. A complementary values and preferences survey helped to assess trade-offs between different key characteristics. RESULTS: The following key attributes for the TPP for a test to confirm HCV viraemic infection were identified: The scope defined is for both HCV detection as well as confirmation of cure. The timeline of development for tests envisioned in the TPP is 5 years. The test should be developed for use by health-care workers or laboratory technicians with limited training in countries with a medium to high prevalence of HCV (1.5-3.5% and >3.5%) and in high-risk populations in low prevalence settings (<1.5%). A clinical sensitivity at a minimum of 90% is considered sufficient (analytical sensitivity of the equivalent of 3000 IU/ml), particularly if the test increases access to testing through an affordable price, increase ease-of-use and feasibility on capillary blood. Polyvalency would be optimal (i.e. ability to test for HIV and others). The only characteristic that full agreement could not be achieved on was the price for a virological test. Discussants felt that to reach the optimal target price substantial trade-offs had to be made (e.g. in regards to sensitivity and integration). CONCLUSION: The TPP and V&P survey results define the need for an easy-to-use, low cost test to increase access to diagnosis and linkage to care in LMIC.

Diagnostic accuracy of serological diagnosis of hepatitis C and B using dried blood spot samples (DBS): two systematic reviews and meta-analyses.

BACKGROUND: Dried blood spots (DBS) are a convenient tool to enable diagnostic testing for viral diseases due to transport, handling and logistical advantages over conventional venous blood sampling. A better understanding of the performance of serological testing for hepatitis C (HCV) and hepatitis B virus (HBV) from DBS is important to enable more widespread use of this sampling approach in resource limited settings, and to inform the 2017 World Health Organization (WHO) guidance on testing for HBV/HCV. METHODS: We conducted two systematic reviews and meta-analyses on the diagnostic accuracy of HCV antibody (HCV-Ab) and HBV surface antigen (HBsAg) from DBS samples compared to venous blood samples. MEDLINE, EMBASE, Global Health and Cochrane library were searched for studies that assessed diagnostic accuracy with DBS and agreement between DBS and venous sampling. Heterogeneity of results was assessed and where possible a pooled analysis of sensitivity and specificity was performed using a bivariate analysis with maximum likelihood estimate and 95% confidence intervals (95%CI). We conducted a narrative review on the impact of varying storage conditions or limits of detection in subsets of samples. The QUADAS-2 tool was used to assess risk of bias. RESULTS: For the diagnostic accuracy of HBsAg from DBS compared to venous blood, 19 studies were included in a quantitative meta-analysis, and 23 in a narrative review. Pooled sensitivity and specificity were 98% (95%CI:95%-99%) and 100% (95%CI:99-100%), respectively. For the diagnostic accuracy of HCV-Ab from DBS, 19 studies were included in a pooled quantitative meta-analysis, and 23 studies were included in a narrative review. Pooled estimates of sensitivity and specificity were 98% (CI95%:95-99) and 99% (CI95%:98-100), respectively. Overall quality of studies and heterogeneity were rated as moderate in both systematic reviews. CONCLUSION: HCV-Ab and HBsAg testing using DBS compared to venous blood sampling was associated with excellent diagnostic accuracy. However, generalizability is limited as no uniform protocol was applied and most studies did not use fresh samples. Future studies on diagnostic accuracy should include an assessment of impact of environmental conditions common in low resource field settings. Manufacturers also need to formally validate their assays for DBS for use with their commercial assays.

Research priorities to achieve universal access to hepatitis C prevention, management and direct-acting antiviral treatment among people who inject drugs.

Globally, it is estimated that 71.1 million people have chronic hepatitis C virus (HCV) infection, including an estimated 7.5 million people who have recently injected drugs (PWID). There is an additional large, but unquantified, burden among those PWID who have ceased injecting. The incidence of HCV infection among current PWID also remains high in many settings. Morbidity and mortality due to liver disease among PWID with HCV infection continues to increase, despite the advent of well-tolerated, simple interferon-free direct-acting antiviral (DAA) HCV regimens with cure rates >95%. As a result of this important clinical breakthrough, there is potential to reverse the rising burden of advanced liver disease with increased treatment and strive for HCV elimination among PWID. Unfortunately, there are many gaps in knowledge that represent barriers to effective prevention and management of HCV among PWID. The Kirby Institute, UNSW Sydney and the International Network on Hepatitis in Substance Users (INHSU) established an expert round table panel to assess current research gaps and establish future research priorities for the prevention and management of HCV among PWID. This round table consisted of a one-day workshop held on 6 September, 2016, in Oslo, Norway, prior to the International Symposium on Hepatitis in Substance Users (INHSU 2016). International experts in drug and alcohol, infectious diseases, and hepatology were brought together to discuss the available scientific evidence, gaps in research, and develop research priorities. Topics for discussion included the epidemiology of injecting drug use, HCV, and HIV among PWID, HCV prevention, HCV testing, linkage to HCV care and treatment, DAA treatment for HCV infection, and reinfection following successful treatment. This paper highlights the outcomes of the roundtable discussion focused on future research priorities for enhancing HCV prevention, testing, linkage to care and DAA treatment for PWID as we strive for global elimination of HCV infection.

Diagnosis of viral hepatitis.

PURPOSE OF REVIEW: Chronic hepatitis B virus (HBV) and hepatitis C virus (HCV) infections and HIV-HBV and HCV coinfection are major causes of chronic liver disease worldwide. Testing and diagnosis is the gateway for access to both treatment and prevention services, but there remains a large burden of undiagnosed infection globally. We review the global epidemiology, key challenges in the current hepatitis testing response, new tools to support the hepatitis global response (2016-2020 Global Hepatitis Health Sector strategy, and 2017 WHO guidelines on hepatitis testing) and future directions and innovations in hepatitis diagnostics. RECENT FINDINGS: Key challenges in the current hepatitis testing response include lack of quality-assured serological and low-cost virological in-vitro diagnostics, limited facilities for testing, inadequate data to guide country-specific hepatitis testing approaches, stigmatization of those with or at risk of viral hepatitis and lack of guidelines on hepatitis testing for resource-limited settings. The new Global Hepatitis Health Sector strategy sets out goals for elimination of viral hepatitis as a public health threat by 2030 and gives outcome targets for reductions in new infections and mortality, as well as service delivery targets that include testing, diagnosis and treatment. The 2017 WHO hepatitis testing guidelines for adults, adolescents and children in low-income and middle-income countries outline the public health approach to strengthen and expand current testing practices for viral hepatitis and addresses who to test (testing approaches), which serological and virological assays to use (testing strategies) as well as interventions to promote linkage to prevention and care. SUMMARY: Future directions and innovations in hepatitis testing include strategies to improve access such as through use of existing facility and community-based testing opportunities for hepatitis testing, near-patient or point-of-care assays for virological markers (nucleic acid testing and HCV core antigen), dried blood spot specimens used with different serological and nucleic acid test assays, multiplex and multi-disease platforms to enable testing for multiple analytes/pathogens and potential self-testing for viral hepatitis.

Early antiretroviral therapy initiation: access and equity of viral load testing for HIV treatment monitoring.

Scaling up access to HIV viral load testing for individuals undergoing antiretroviral therapy in low-resource settings is a global health priority, as emphasised by research showing the benefits of suppressed viral load for the individual and the whole population. Historically, large-scale diagnostic test implementation has been slow and incomplete because of service delivery and other challenges. Building on lessons from the past, in this Personal View we propose a new framework to accelerate viral load scale-up and ensure equitable access to this essential test. The framework includes the following steps: (1) ensuring adequate financial investment in scaling up this test; (2) achieving pricing agreements and consolidating procurement to lower prices of the test; (3) strengthening functional tiered laboratory networks and systems to expand access to reliable, high-quality testing across countries; (4) strengthening national leadership, with prioritisation of laboratory services; and (5) demand creation and uptake of test results by clinicians, nurses, and patients, which will be vital in ensuring viral load tests are appropriately used to improve the quality of care. The use of dried blood spots to stabilise and ship samples from clinics to laboratories, and the use of point-of-care diagnostic tests, will also be important for ensuring access, especially in settings with reduced laboratory capacity. For countries that have just started to scale up viral load testing, lessons can be learnt from countries such as Botswana, Brazil, South Africa, and Thailand, which have already established viral load programmes. This framework might be useful for guiding the implementation of viral load with the aim of achieving the new global HIV 90-90-90 goals by 2020.

Scale-up of Routine Viral Load Testing in Resource-Poor Settings: Current and Future Implementation Challenges.

Despite immense progress in antiretroviral therapy (ART) scale-up, many people still lack access to basic standards of care, with our ability to meet the Joint United Nations Programme on HIV/AIDS 90-90-90 treatment targets for HIV/AIDS dependent on dramatic improvements in diagnostics. The World Health Organization recommends routine monitoring of ART effectiveness using viral load (VL) testing at 6 months and every 12 months, to monitor treatment adherence and minimize failure, and will publish its VL toolkit later this year. However, the cost and complexity of VL is preventing scale-up beyond developed countries and there is a lack of awareness among clinicians as to the long-term patient benefits and its role in prolonging the longevity of treatment programs. With developments in this diagnostic field rapidly evolving-including the recent improvements for accurately using dried blood spots and the imminent appearance to the market of point-of-care technologies offering decentralized diagnosis-we describe current barriers to VL testing in resource-limited settings. Effective scale-up can be achieved through health system and laboratory system strengthening and test price reductions, as well as tackling multiple programmatic and funding challenges.

Sustainable HIV treatment in Africa through viral-load-informed differentiated care.

There are inefficiencies in current approaches to monitoring patients on antiretroviral therapy in sub-Saharan Africa. Patients typically attend clinics every 1 to 3 months for clinical assessment. The clinic costs are comparable with the costs of the drugs themselves and CD4 counts are measured every 6 months, but patients are rarely switched to second-line therapies. To ensure sustainability of treatment programmes, a transition to more cost-effective delivery of antiretroviral therapy is needed. In contrast to the CD4 count, measurement of the level of HIV RNA in plasma (the viral load) provides a direct measure of the current treatment effect. Viral-load-informed differentiated care is a means of tailoring care so that those with suppressed viral load visit the clinic less frequently and attention is focussed on those with unsuppressed viral load to promote adherence and timely switching to a second-line regimen. The most feasible approach to measuring viral load in many countries is to collect dried blood spot samples for testing in regional laboratories; however, there have been concerns over the sensitivity and specificity of this approach to define treatment failure and the delay in returning results to the clinic. We use modelling to synthesize evidence and evaluate the cost-effectiveness of viral-load-informed differentiated care, accounting for limitations of dried blood sample testing. We find that viral-load-informed differentiated care using dried blood sample testing is cost-effective and is a recommended strategy for patient monitoring, although further empirical evidence as the approach is rolled out would be of value. We also explore the potential benefits of point-of-care viral load tests that may become available in the future.

Errors generated by a point-of-care CD4+ T-lymphocyte analyser: a retrospective observational study in nine countries.

OBJECTIVE: To estimate the proportion of invalid results generated by a CD4+ T-lymphocyte analyser used by Médecins Sans Frontières (MSF) in field projects and identify factors associated with invalid results. METHODS: We collated 25,616 CD4+ T-lymphocyte test results from 39 sites in nine countries for the years 2011 to 2013. Information about the setting, user, training, sampling technique and device repair history were obtained by questionnaire. The analyser performs a series of checks to ensure that all steps of the analysis are completed successfully; if not, an invalid result is reported. We calculated the proportion of invalid results by device and by operator. Regression analyses were used to investigate factors associated with invalid results. FINDINGS: There were 3354 invalid test results (13.1%) across 39 sites, for 58 Alere PimaTM devices and 180 operators. The median proportion of errors per device and operator was 12.7% (interquartile range, IQR: 10.3-19.9) and 12.1% (IQR: 7.1-19.2), respectively. The proportion of invalid results varied widely by country, setting, user and device. Errors were not associated with settings, user experience or the number of users per device. Tests performed on capillary blood samples were significantly less likely to generate errors compared to venous whole blood. CONCLUSION: The Alere Pima CD4+ analyser generated a high proportion of invalid test results, across different countries, settings and users. Most error codes could be attributed to the operator, but the exact causes proved difficult to identify. Invalid results need to be factored into the implementation and operational costs of routine CD4+ T-lymphocyte testing.

Simplified diagnostic monitoring for hepatitis C, in the new era of direct-acting antiviral treatment.

PURPOSE OF REVIEW: Approximately 150-175 million people are infected with hepatitis C virus (HCV). Until very recently, the complexity, cost and poor efficacy and tolerability of pegylated interferon and ribavirin (PEG-RBV) treatment have hindered scale up in low-income and middle-income countries (L&MICs). Similarly, the diagnostic and monitoring algorithm associated with PEG-RBV has been expensive and complicated because of the poor efficacy and frequency of adverse drug effects of PEG-RBV therapy. This article provides an overview of the potential changes to the diagnosis and monitoring algorithm and describes key promising tools in the diagnostics pipeline. RECENT FINDINGS: Interferon-free direct-acting antiviral (DAA) therapy sets the stage to significantly simplify laboratory requirements and make the overall diagnostic package much less expensive. Diagnostic simplification and cost-reduction will be key to enable implementation of HCV screening and treatment in L&MICs. SUMMARY: There is the potential to introduce simplified monitoring for hepatitis C. Antigen testing could be used as a replacement for HCV RNA PCR tests, to establish active infection and then to prove cure after stopping DAA treatment. If new DAA treatments can be shown to be pan-genotypic, genotyping may no longer be required.