Challenges and opportunities for the implementation of virological testing in resource-limited settings

The rollout of paediatric dolutegravir and virological outcomes among children living with HIV in Mozambique

Background

In 2022, Mozambique introduced Dolutegravir 10mg (pDTG), as part of paediatric antiretroviral therapy for children weighing < 20 kg. Understanding real-world challenges during national rollout can strengthen health systems in resource-limited settings.

Objectives

We described the transition rate to, and new initiation of, pDTG, viral load suppression (VLS) post-pDTG, and factors associated with VLS among children living with HIV.

Method

We conducted a retrospective cohort study involving children aged < 9 years and abstracted data from clinical sources. We used logistic regression to assess VLS and pDTG initiation predictors.

Results

Of 1353 children, 1146 initiated pDTG; 196 (14.5%) had no recorded weight. Post-pDTG switch, 98.9% (950/961) of children maintained the same nucleoside reverse transcriptase inhibitor backbone. After initiating Abacavir/Lamivudine+pDTG, 834 (72.8%) children remained on the regimen, 156 (13.6%) switched off (majority to Dolutegravir 50mg), 22 (1.9%) had ≥ 2 anchor drug switches; 134 (11.7%) had no documented follow-up regimen. Factors associated with pDTG initiation or switch were younger age (adjusted odds ratio [AOR] = 0.71 [0.63-0.80]) and a recorded weight (AOR = 55.58 [33.88-91.18]). VLS among the 294 children with a viral load (VL) test after ≥ 5 months post-pDTG was 75.5% (n = 222/294). Pre-pDTG VLS rate among treatment-experienced children was 56.5% (n = 130/230). Factors associated with VLS were older age (AOR = 1.18 [1.03-1.34]) and previous VLS (AOR = 2.27 [1.27-4.06]).

Conclusion

Most eligible children initiated pDTG per guidelines, improving post-pDTG VLS. Challenges included unexplained switches off pDTG after initiation, low VL coverage and inadequate documentation in clinic records.

Changes in access to viral load testing, incidence rates of viral load suppression and rebound following the introduction of the 'universal test and treat' guidelines in Cameroon: A retrospective follow-up analysis

Cameroon adopted and started implementing in 2016, the 'universal test and treat' (UTT) guidelines to fast-track progress towards the 95-95-95 ambitious targets to end the HIV epidemic. Achieving the third 95 (viral load suppression) is the most desirable target in HIV care. We aimed to evaluate the effectiveness of this novel approach on access to viral load testing (VLT), viral suppression (VLS), and viral load rebound (VLR). A retrospective cohort study was conducted at The Nkongsamba Regional Hospital to compare VLT outcomes between the pre-UTT (2002 to 2015) and the post-UTT (2016 to 2020) periods. We used a data extraction form to collect routine data on adult patients living with HIV. We measured uptake levels of the first and serial VLT and compared the incidence rates of VLS (VL<1000 copies/ml) and viral load rebound (VLR) before and after introducing the UTT approach using Kaplan Meier plots and log-rank tests. Cox regression was used to screen for factors independently associated with VLS and VLR events between the guideline periods. Access to initial VLT increased significantly from 6.11% to 25.56% at 6 months and from 12.00% to 73.75% at 12 months before and after introducing the UTT guidelines respectively. After a total observation time at risk of 17001.63 person-months, the UTT group achieved an incidence rate of 90.36 VLS per 1000 person-months, four-fold higher than the 21.71 VLS per 1000 person-months observed in the pre-UTT group (p<0.0001). After adjusting for confounding, the VLS rate was about 6-fold higher in the UTT group than in the pre-UTT group (adjusted Hazard Rate (aHR) = 5.81 (95% confidence interval (95%CI): 4.43-7.60). The incidence of VLR increased from 12.60 (95%CI: 9.50-16.72) to 19.11 (95%CI: 14.22-25.67) per 1000 person-months before and after the introduction of UTT guidelines respectively. After adjusting, VLR was more than twice as high in the UTT group than in the pre-UTT group (aHR = 2.32, 95%CI: 1.30-4.13). Increased access to initial VLT and higher rates of VLS have been observed but there are concerns that the suppressed viral load may not be durable since the introduction of the UTT policy in this setting.

Body mass index, proteinuria and total lymphocyte counts in predicting treatment responses among ART naïve individuals with HIV initiated on antiretroviral treatment in Dar es Salaam, Tanzania, 2019: a cohort study

OBJECTIVES

To explore the potential use of body mass index (BMI), proteinuria and total lymphocyte count changes in predicting immunological and virological response in individuals with HIV initiated on antiretroviral treatment (ART).

DESIGN

Prospective cohort study.

SETTING

Three urban HIV care and treatment centres in Dar es Salaam.

PARTICIPANTS

Individuals with HIV initiating ART.

OUTCOME MEASURES

HIV viral load ≥1000 copies/mL (viral non-suppression) at 6 months after ART initiation.

RESULTS

Of 215 (out of 220 enrolled) participants who returned for evaluation at 6 months, 147 (66.8%) were women. At 6 months of follow-up, 89.4% (76/85) of participants with sustained weight gain were virally suppressed compared with 31.8% (7/22) with sustained loss, p<0.001. In participants who were lymphopaenic at baseline, an increase to normal total lymphocyte counts at 6 months was associated with an increase in CD4 count compared with participants who remained lymphopaenic, 96.2% (50/52) versus 54.8% (17/31), p<0.001. At baseline, 50.0% (110/220) had proteinuria. In participants without proteinuria from baseline to 6 months, 89.8% (79/88) were virally suppressed compared with participants with proteinuria at baseline and/or 3 months, 85.6% (77/90), those with persistent proteinuria, 30.8% (8/26), and proteinuria at 6 months only, 45.5% (5/11), p<0.001. In modified Poisson regression, the independent predictors other than CD4 cell counts for viral non-suppression at 6 months among individuals with HIV initiating on ART were BMI loss >5% from baseline to 6 months (adjusted RR 2.73, 95% CI (1.36 to 5.47)), lymphopaenia at 6 months (adjusted RR=4.54, 95% CI (2.19 to 9.39)) and proteinuria at 6 months (adjusted RR=2.63, 95% CI (1.25 to 5.54)).

CONCLUSIONS

Change in BMI, total lymphocyte count and presence of proteinuria can monitor and predict ART response and may be particularly helpful in settings when CD4 counts and viral load monitoring are unavailable.

An elution independent collection device (EICD) for rapid collection of Anaplasma marginale DNA from blood samples

Currently utilized molecular detection methods are based mainly on nucleic acid extraction, amplification, and detection procedures that may require costly equipment, numerous reagents, and highly trained personnel. These requirements make diagnostic tests expensive, time-consuming, and not suitable for point-of-care applications. There is an increasing demand for simple, low-cost portable technologies. To overcome these challenges, a paper-based elution independent collection device (EICD) was designed to collect microorganisms and recover nucleic acids for molecular biology applications with minimal steps. In this study, we demonstrate a simpler Anaplasma marginale detection that uses an EICD for nucleic acid collection combined with recombinase polymerase amplification (RPA), and a lateral flow dipstick for detection of the specified target. A pre-lysis blood treatment was optimized that uses Triton X-100 lysis buffer and bovine serum album in wash buffer. Blood samples were incubated for 5 min at room temperature and run through the EICD. Four 1-mm diameter discs excised from EICD were used as template in basic RPA and lateral flow (nfo) (endonuclease IV) RPA assays. Each disc of soluble central membrane (SCM) carried circa 0.249 pg/µl of Anaplasma DNA. The percentage of nucleic acid recoverable from the SCM ranged between 60% - 70%. Blood samples infected with A. marginale were treated with Triton X-100 pre-lysis protocol. All samples tested positive by PCR and RPA methods. EICD-driven collection of blood samples is a practical method successfully adapted to detect Anaplasma spp. or blood-borne pathogen DNA and has potential for point-of-care detection in resource-limited settings.

Virologic failure and switch to second-line antiretroviral therapy in children with HIV in Lilongwe, Malawi: an observational cohort study

BACKGROUND

As routine viral load testing among HIV-infected individuals on antiretroviral therapy (ART) expands, virologic failure (VF) among children in developing countries remains poorly understood. We assessed the rate of VF, the proportion failing who were subsequently switched to second-line ART and factors associated with VF among children ≤18 y.

METHODS

An observation cohort study among 1312 children at two public clinics in Lilongwe, Malawi who initiated a first-line ART regimen between January 2014 and December 2017 and remained on treatment for ≥6 mo was conducted. Kaplan-Meier methods estimated the probabilities of VF. Univariable and multivariable Poisson regression models were used to explore predictors of VF.

RESULT

Overall, 16% (208/1312) of children experienced VF with an incidence rate of 10.1 events per 100 person-years. Of the 208, 184 (88%) were switched to second-line ART: 68 (43%) switched the same day VF was confirmed and 106 (66%) switched within 90 d of confirmed VF. Use of a Nevirapine (NVP)-based regimen and initiating ART in 2016-2017 compared with 2014-2015 were independent predictors of VF.

CONCLUSION

VF is common among children receiving ART. The findings suggest that VF can be reduced by phasing out NVP-based regimen and by ensuring optimal adherence to ART.

Measuring and explaining inequality of continuous care for people living with HIV receiving antiretroviral therapy in Kunming, China

Background

In the context of scaling up free antiretroviral therapy (ART), healthcare equality is essential for people living with HIV. We aimed to assess socioeconomic-related inequalities in uptake of continuous care for people living with HIV receiving ART, including retention in care in the last six months, routine toxicity monitoring, adequate immunological and virological monitoring, and uptake of mental health assessment in the last 12 months. We also determined the contributions of socioeconomic factors to the degree of inequalities.

Methods

A hospital-based cross-sectional survey was conducted among consecutive clients visiting an HIV treatment center in Kunming, China in 2019. Participants were 702 people living with HIV aged ≥18 years (median age: 41.0 years, 69.4% male) who had been on ART for 1–5 years. Socioeconomic-related inequality and its contributing factors were assessed by a normalized concentration index (CI_n) with a decomposition approach.

Results

The uptake of mental health assessment was low (15%) but significantly higher among the rich (CI_n 0.1337, 95% CI: 0.0140, 0.2534). Retention in care, toxicity, and immunological monitoring were over 80% but non-significant in favor of the rich (CI_n: 0.0117, 0.0315, 0.0736, respectively). The uptake of adequate virological monitoring was 15% and higher among the poor (CI_n = -0.0308). Socioeconomic status positively contributed to inequalities of all care indicators, with the highest contribution for mental health assessment (124.9%) and lowest for virological monitoring (2.7%).

Conclusions

These findings suggest virological monitoring and mental health assessment be given more attention in long-term HIV care. Policies allocating need-oriented resources geared toward improving equality of continuous care should be developed.

Infant HIV diagnosis and turn-around time for testing in Malawi, 2015

Background

For HIV-exposed infants in Malawi, there are missed opportunities at each step of the testing and treatment cascade.

Objective

This study assessed factors associated with HIV positivity among infants in Malawi and turn-around times for infant HIV testing.

Methods

HIV testing data for infants aged 0–18 months from 2012 to 2015 were extracted from the Malawi HIV laboratory information management system and analysed using logistic regression. Turn-around time was defined as time between collection of samples to results dispatch from the laboratory.

Results

A total of 106 997 tests were included in the analyses. A subset of 76 006 observations with complete dates were included in the turn-around time analysis. Overall positivity was 4.2%. Factors associated with positivity were increasing age (infants aged 3–6 months: adjusted odds ratio [aOR] = 2.24; infants aged 6–9 months: aOR = 3.42; infants aged > 9 months: aOR = 4.24), female sex (aOR = 1.08) and whether the mother was alive and not on antiretroviral therapy at time of the infant’s test (aOR = 1.57). Provision of HIV prophylaxis to the infant after birth (aOR = 0.38) was found to be protective against HIV positivity. The median turn-around time was 24 days (increased from 19 to 34 days between 2012 and 2015).

Conclusion

Infant HIV positivity has decreased in Malawi, whereas turn-around time has increased. Factors associated with positivity include increasing age, female sex, and whether the mother was alive and not on antiretroviral therapy at the time of the infant’s test.

An open-source molecular diagnostic platform approach for outbreak and epidemic preparedness

Background

Diagnostic development for outbreak pathogens has typically followed a disease-specific reactive rather than proactive response. Given the diversity of outbreak pathogens, particularly those prioritised by the World Health Organization Research and Development Blueprint, a more flexible and proactive approach to epidemic preparedness is needed to expand access to critical molecular diagnostic tests in peripheral and resource-constrained deployment settings.

Objective

New and more sustainable directives are needed to spur the development of high-quality products, particularly for epidemics more often found in low- and middle-income countries. To leverage and de-risk the development process, we present the benefits and challenges of an open-source business model for co-development of molecular diagnostic tests for decentralised settings.

Methods

We identify key outbreak pathogens that are available only for testing in high infrastructure laboratories and compare in-country installed base platforms that could be leveraged for menu expansion. Key strengths and challenges for development are highlighted for both platform and assay developers, with discussion of how to leverage and de-risk the process through an open-source development model.

Results

Depending on the specific partner strengths, options for partnership roles are presented. The proposed open-source business model addresses the particular challenges in the detection of outbreak- and epidemic-prone pathogens in low- and middle-income countries, reduces development and deployment risks to support outbreak response, strengthens diagnostic capacity and creates a viable market for product developers.

Conclusion

We hope this model for a collaborative and open-source approach for molecular diagnostics serves to encourage stakeholders to consider co-development partnerships to improve outbreak preparedness and epidemic/pandemic response.

Pooled testing: A tool to increase efficiency of infant HIV diagnosis and virological monitoring

Background

Pooled testing, or pooling, has been used for decades to efficiently diagnose relatively rare conditions, such as infection in blood donors. Programmes for the prevention of mother-to-child transmission of HIV and for antiretroviral therapy (ART) are being rolled out in much of Africa and are largely successful. This increases the need for early infant diagnosis (EID) of HIV using qualitative nucleic acid testing and for virological monitoring of patients on ART using viral load testing. While numbers of patients needing testing are increasing, infant HIV infections and ART failures are becoming rarer, opening an opportunity for pooled testing approaches.

Aim

This review highlights the need for universal EID and viral load coverage as well as the challenges faced. We introduce the concept of pooled testing and highlight some important considerations before giving an overview of studies exploring pooled testing for EID and virological monitoring.

Results

For ART monitoring, pooling has been shown to be accurate and efficient; for EID it has not been tried although modelling shows it to be promising. The final part attempts to place pooling into the context of current mother-to-child transmission of HIV and ART programmes and their expected trajectories over the next years.

Conclusion

Several points warrant consideration: pre-selection to exclude samples with an elevated pre-test probability of positivity from pooled testing, the use of dried blood or plasma spots, and choosing a pooling strategy that is both practically feasible and economical. Finally, novel ideas are suggested to make pooling even more attractive.

Incidence and predictors of virological failure among adult HIV patients on first-line antiretroviral therapy in Amhara regional referral hospitals; Ethiopia: a retrospective follow-up study

Background

Although the United Nations program on HIV/AIDS 90–90-90-targets recommends achieving 90% of viral suppression for patients on first-line antiretroviral therapy by 2020, virological failure is still high and it remains a global public health problem. Therefore, assessing the incidence and predictors of virological failure among adult HIV patients on first-line ART in Amhara regional referral hospitals, Ethiopia is vital to design appropriate prevention strategies for treatment failure and preventing the unnecessary switching to second-line regimens.

Method

An institution-based retrospective follow-up study was conducted on 490 adult HIV patients. The simple random sampling technique was used, and data were entered into Epi data Version 4.2.0.0 and was exported to Stata version 14 for analysis. The proportional hazard assumption was checked, and the Weibull regression was fitted. Cox-Snell residual was used to test the goodness of fit, and the appropriate model was selected by AIC/BIC. Finally, an adjusted hazard ratio with a 95% CI was computed, and variables with P-value < 0.05 in the multivariable analysis were taken as significant predictors of virological failure.

Results

The overall incidence rate of virological failure was 4.9 events per 1000 person-month observations (95%CI: 3.86–6.38). Users of CPT (AHR = 0.55, 95%CI: 0.31–0.97), poor adherence (AHR = 5.46, 95%CI: 3.07–9.74), CD4 Count <=200 cells/mm³ (AHR = 3.9, 95%CI: 1.07–13.9) and 201–350 cells/mm³ (AHR 4.1, 95%CI: 1.12–15) respectively, and NVP based first line drug regimen (AHR = 3.53, 95%CI: 1.73–7.21) were significantly associated with virological failure.

Conclusion

The incidence rate of virological failure was high. CPT, poor adherence, low baseline CD4 count and NVP based first-line drug regimen were independent risk factors associated with virological failure. Therefore, strengthening HIV care intervention and addressing these significant predictors is highly recommended in the study setting.

Challenges and barriers to HIV service uptake and delivery along the HIV care cascade in Cameroon

Introduction

The year 2017 marked a transition period with the end of the implementation of Cameroon´s 2014-2017 HIV/AIDS National Strategic Plan (NSP) and the development of the 2018-2022 NSP. We assessed barriers and challenges to service delivery and uptake along the HIV care cascade in Cameroon to inform decision making within the framework of the new NSP, to achieve the UNAIDS 90-90-90 target.

Methods

We conducted a cross sectional descriptive study nationwide, enrolling HIV infected patients and staff. Data were collected on sociodemographic characteristics, HIV testing, antiretroviral therapy and viral load testing delivery and uptake and factors that limit their access.

Results

A total of 137 staff and 642 people living with HIV (PLHIV) were interviewed. Of 642 PLHIV with known status, 339 (53%) repeated their HIV test at least once, with range: 1-10 and median: 2 (IQR: 1-3). Having attained secondary level of education (OR: 2.07, 95% CI: 1.04-4.14; P=0.04) or more (OR: 2.91, 95% CI: 1.16-7.28; P=0.02) were significantly associated with repeat testing. Psychological (refusal of service uptake and existence of HIV), community-level (stigmatization and fear of confidentiality breach) and commodity stock-outs “HIV test kits (21%), antiretrovirals (ARVs) (71.4%), viral load testing reagents (100%)” are the major barriers to service delivery and uptake along the cascade.

Conclusion

We identified individual, community-level, socio-economic and health care system related barriers which constitute persistent bottlenecks in HIV service delivery and uptake and a high rate of repeat testing by PLHIV with known status. Addressing all these accordingly can help the country achieve the UNAIDS 90-90-90 target.

Point-of-care viral load monitoring: outcomes from a decentralized HIV programme in Malawi

Introduction

Routinely monitoring the HIV viral load (VL) of people living with HIV (PLHIV) on anti‐retroviral therapy (ART) facilitates intensive adherence counselling and faster ART regimen switch when treatment failure is indicated. Yet standard VL‐testing in centralized laboratories can be time‐intensive and logistically difficult in low‐resource settings. This paper evaluates the outcomes of the first four years of routine VL‐monitoring using Point‐of‐Care technology, implemented by Médecins Sans Frontières (MSF) in rural clinics in Malawi.

Methods

We conducted a retrospective cohort analysis of patients eligible for routine VL‐ testing between 2013 and 2017 in four decentralized ART‐clinics and the district hospital in Chiradzulu, Malawi. We assessed VL‐testing coverage and the treatment failure cascade (from suspected failure (first VL>1000 copies/mL) to VL suppression post regimen switch). We used descriptive statistics and multivariate logistic regression to assess factors associated with suspected failure.

Results and Discussion

Among 21,400 eligible patients, VL‐testing coverage was 85% and VL suppression was found in 89% of those tested. In the decentralized clinics, 88% of test results were reviewed on the same day as blood collection, whereas in the district hospital the median turnaround‐time for results was 85 days. Among first‐line ART patients with suspected failure (N = 1544), 30% suppressed (VL<1000 copies/mL), 35% were treatment failures (confirmed by subsequent VL‐testing) and 35% had incomplete VL follow‐up. Among treatment failures, 80% (N = 540) were switched to a second‐line regimen, with a higher switching rate in the decentralized clinics than in the district hospital (86% vs. 67%, p < 0.01) and a shorter median time‐to‐switch (6.8 months vs. 9.7 months, p < 0.01). Similarly, the post‐switch VL‐testing rate was markedly higher in the decentralized clinics (61% vs. 26%, p < 0.01). Overall, 79% of patients with a post‐switch VL‐test were suppressed.

Conclusions

Viral load testing at the point‐of‐care in Chiradzulu, Malawi achieved high coverage and good drug regimen switch rates among those identified as treatment failures. In decentralized clinics, same‐day test results and shorter time‐to‐switch illustrated the game‐changing potential of POC‐based VL‐testing. Nevertheless, gaps were identified along all steps of the failure cascade. Regular staff training, continuous monitoring and creating demand are essential to the success of routine VL‐testing.

Tuberculosis, HIV, and viral hepatitis diagnostics in eastern Europe and central Asia: high time for integrated and people-centred services

Globally, high rates (and in the WHO European region an increasing prevalence) of co-infection with tuberculosis and HIV and HIV and hepatitis C virus exist. In eastern European and central Asian countries, the tuberculosis, HIV, and viral hepatitis programmes, including diagnostic services, are separate vertical structures. In this Personal View, we consider underlying reasons for the poor integration for these diseases, particularly in the WHO European region, and how to address this with an initial focus on diagnostic services. In part, this low integration has reflected different diagnostic development histories, global funding sources, and sample types used for diagnosis (eg, typically sputum for tuberculosis and blood for HIV and hepatitis C). Cooperation between services improved as patients with tuberculosis needed routine testing for HIV and vice versa, but financial, infection control, and logistical barriers remain. Multidisease diagnostic platforms exist, but to be used optimally, appropriate staff training and sensible understanding of different laboratory and infection control risks needs rapid implementation. Technically these ideas are all feasible. Poor coordination between these vertical systems remains unhelpful. There is a need to increase political and operational integration of diagnostic and treatment services and bring them closer to patients.

The association of memory disorders and chronic HIV disease in the antiretroviral therapy era: a systematic literature review

OBJECTIVES

Despite recent pharmacological progress, memory impairment is still frequently reported in people living with HIV. We aimed to conduct a systematic literature review investigating the presence of impairment of (sub)components of memory function in patients prescribed highly active antiretroviral therapy (ART).

METHODS

We adopted a cognitive neuropsychological model of memory function as the theoretical framework, distinguishing between a short-term working memory component and a long-term component of memory, along with their specific (sub)components. We systematically searched for the presence of impairment of each (sub)component in the selected papers. Careful consideration was given to study design and methods and control of covariates.

RESULTS

Only the central executive component of working memory has been consistently reported to be impaired in HIV infection. The other two (sub)components, namely the phonological loop and the visuospatial sketchpad, were unimpaired. Discordant results have been obtained as to verbal and visual episodic memory, as some authors reported an association with HIV infection, whereas others did not. There is little evidence for semantic memory deficit in HIV infection, while there are suggestions that the neural substrate of implicit memory may be damaged by the effects of HIV infection and inflammation. Most studies in this area have been conducted in small samples and with poor control for covariates. Thus, conclusions regarding the association of memory dysfunction with HIV infection are hampered by methodological issues such as selection bias and unmeasured confounding.

CONCLUSIONS

The task remains for future research to ascertain the impact of HIV infection on memory function.

Diagnostic tests for Crimean-Congo haemorrhagic fever: a widespread tickborne disease

Crimean-Congo haemorrhagic fever (CCHF) is a widespread tickborne disease that circulates in wild and domestic animal hosts, and causes severe and often fatal haemorrhagic fever in infected humans. Due to the lack of treatment options or vaccines, and a high fatality rate, CCHF virus (CCHFV) is considered a high-priority pathogen according to the WHO R&D Blueprint. Several commercial reverse transcriptase PCR (RT-PCR) and serological diagnostic assays for CCHFV are already available, including febrile agent panels to distinguish CCHFV from other viral haemorrhagic fever agents; however, the majority of international laboratories use inhouse assays. As CCHFV has numerous amplifying animal hosts, a cross-sectoral 'One Health' approach to outbreak prevention is recommended to enhance notifications and enable early warning for genetic and epidemiological shifts in the human, animal and tick populations. However, a lack of guidance for surveillance in animals, harmonisation of case identification and validated serodiagnostic kits for animal testing hinders efforts to strengthen surveillance systems. Additionally, as RT-PCR tests tend to be lineage-specific for regional circulating strains, there is a need for pan-lineage sensitive diagnostics. Adaptation of existing tests to point-of-care molecular diagnostic platforms that can be implemented in clinic or field-based settings would be of value given the potential for CCHFV outbreaks in remote or low-resource areas. Finally, improved access to clinical specimens for validation of diagnostics would help to accelerate development of new tests. These gaps should be addressed by updated target product profiles for CCHFV diagnostics.

An updated roadmap for MERS-CoV research and product development: focus on diagnostics

Diagnostics play a central role in the early detection and control of outbreaks and can enable a more nuanced understanding of the disease kinetics and risk factors for the Middle East respiratory syndrome-coronavirus (MERS-CoV), one of the high-priority pathogens identified by the WHO. In this review we identified sources for molecular and serological diagnostic tests used in MERS-CoV detection, case management and outbreak investigations, as well as surveillance for humans and animals (camels), and summarised the performance of currently available tests, diagnostic needs, and associated challenges for diagnostic test development and implementation. A more detailed understanding of the kinetics of infection of MERS-CoV is needed in order to optimise the use of existing assays. Notably, MERS-CoV point-of-care tests are needed in order to optimise supportive care and to minimise transmission risk. However, for new test development, sourcing clinical material continues to be a major challenge to achieving assay validation. Harmonisation and standardisation of laboratory methods are essential for surveillance and for a rapid and effective international response to emerging diseases. Routine external quality assessment, along with well-characterised and up-to-date proficiency panels, would provide insight into MERS-CoV diagnostic performance worldwide. A defined set of Target Product Profiles for diagnostic technologies will be developed by WHO to address these gaps in MERS-CoV outbreak management.

Temporal Improvements in Long-term Outcome in Care Among HIV-infected Children Enrolled in Public Antiretroviral Treatment Care: An Analysis of Outcomes From 2004 to 2012 in Zimbabwe

BACKGROUND

Increasing numbers of children are requiring long-term HIV care and antiretroviral treatment (ART) in public ART programs in Africa, but temporal trends and long-term outcomes in care remain poorly understood.

METHODS

We analyzed outcomes in a longitudinal cohort of infants (<2 years of age) and children (2-10 years of age) enrolling in a public tertiary ART center in Zimbabwe over an 8-year period (2004-2012).

RESULTS

The clinic enrolled 1644 infants and children; the median age at enrollment was 39 months (interquartile range: 14-79), with a median CD4% of 17.0 (interquartile range: 11-24) in infants and 15.0 (9%-23%) in children (P = 0.0007). Among those linked to care, 33.5% dropped out of care within the first 3 months of enrollment. After implementation of revised guidelines in 2009, decentralization of care and increased access to prevention of mother to child transmission services, we observed an increase in infants (48.9%-68.3%; P < 0.0001) and children (48.9%-68.3%; P < 0.0001) remaining in care for more than 3 months. Children enrolled from 2009 were younger, had lower World Health Organization clinical stage, improved baseline CD4 counts than those who enrolled in 2004-2008. Long-term retention in care also improved with decreasing risk of loss from care at 36 months for infants enrolled from 2009 (aHR: 0.57; 95% confidence interval: 0.34-0.95; P = 0.031). ART eligibility at enrollment was a significant predictor of long-term retention in care, while delayed ART initiation after 5 years of age resulted in failure to fully reconstitute CD4 counts to age-appropriate levels despite prolonged ART.

CONCLUSIONS

Significant improvements have been made in engaging and retaining children in care in public ART programs in Zimbabwe. Guideline and policy changes that increase access and eligibility will likely to continue to support improvement in pediatric HIV outcomes.

A targeted approach for routine viral load monitoring in Malawian adults on antiretroviral therapy

OBJECTIVES

WHO recommends HIV viral load (VL) testing 6 months after antiretroviral therapy (ART) initiation and every 12 months thereafter, but cost prohibits routine, universal VL testing in many developing countries. We sought to devise a targeted approach to routine VL monitoring that could reduce cost and identify those at low risk for virologic failure (VF).

METHODS

We analysed screening data from a clinical trial enrolling adults on ART in Malawi. We identified risk factors associated with VF and employed the Knill-Jones method to assign summary score identifying persons at lower risk for VF.

RESULTS

Among 957 adults, prevalence of VF was 9.4%. Factors independently associated with VF included age <38 years (OR 3.44, 95% CI 2.01-5.89), ART duration >2.5 years (OR 2.98, 95% CI 1.79-4.96), ART adherence <95% (OR 1.76, 95% CI 1.06-2.94), CD4 count <200 cells/μl (OR 5.94, 95% CI 3.27-10.78), haemoglobin <13 g/dl (OR 2.76, 95% CI 1.70-4.50) and CD8 count >885 cells/μl (OR 2.10, 95% CI 1.28-3.44). Our VF prediction summary score included all factors above except CD8 count and was fairly accurate with validated area under receiver operating characteristic curve of 0.76. Implementation could reduce VL testing by 65%.

CONCLUSION

A simple score incorporating age, ART duration and adherence, and CD4 count can accurately identify adults at low risk for VF in a sub-Saharan African setting. In areas with high ART utilisation and limited VL testing capacity, a targeted approach could optimise routine VL monitoring while identifying adults in need of alternate ART regimens.

Factors impacting antiretroviral therapy adherence among human immunodeficiency virus-positive adolescents in Sub-Saharan Africa: a systematic review

OBJECTIVES

Eighty-two percent of human immunodeficiency virus (HIV)-positive adolescents live in Sub-Saharan Africa (SSA). Despite the availability of antiretroviral therapy (ART), adherence levels are suboptimal, leading to poor outcomes. This systematic review investigated factors impacting ART adherence among adolescents in SSA, including religious beliefs and intimate relationships.

METHODS

A systematic review was conducted between June and August 2016 using eight electronic databases, including Cochrane and PubMed. Published, ongoing and unpublished research, conducted in SSA from 2004 to 2016, was identified and thematic analysis was used to summarise findings.

RESULTS

Eleven studies from eight SSA countries, published in English between 2011 and 2016, reported on factors impacting ART adherence among adolescents living with HIV (ALHIV). Forty-four barriers and 29 facilitators to adherence were identified, representing a complex web of factors. The main barriers were stigma, ART side-effects, lack of assistance and forgetfulness. Facilitators included caregiver support, peer support groups and knowledge of HIV status.

CONCLUSIONS

Stigma reflects difficult relations between ALHIV and their HIV-negative peers and adults. Most interventions target only those with HIV, suggesting a policy shift towards the wider community could be beneficial. Recommendations include engaging religious leaders and schools to change negative societal attitudes. Limitations of the review include the urban settings and recruitment of predominantly vertically infected participants in most included studies. Therefore, the findings cannot be extrapolated to ALHIV residing in rural locations or horizontally infected ALHIV, highlighting the need for further research in those areas.

Multidisease testing for HIV and TB using the GeneXpert platform: A feasibility study in rural Zimbabwe

BACKGROUND

HIV Viral Load and Early Infant Diagnosis technologies in many high burden settings are restricted to centralized laboratory testing, leading to long result turnaround times and patient attrition. GeneXpert (Cepheid, CA, USA) is a polyvalent near point-of-care platform and is widely implemented for Xpert MTB/RIF diagnosis. This study sought to evaluate the operational feasibility of integrated HIV VL, EID and MTB/RIF testing in new GeneXpert platforms.

METHODS

Whole blood samples were collected from consenting patients due for routine HIV VL testing and DBS samples from infants due for EID testing, at three rural health facilities in Zimbabwe. Sputum samples were collected from all individuals suspected of TB. GeneXpert testing was reserved for all EID, all TB suspects and priority HIV VL at each site. Blood samples were further sent to centralized laboratories for confirmatory testing. GeneXpert polyvalent testing results and patient outcomes, including infrastructural and logistical requirements are reported. The study was conducted over a 10-month period.

RESULTS

The fully automated GeneXpert testing device, required minimal training and biosafety considerations. A total of 1,302 HIV VL, 277 EID and 1,581 MTB/RIF samples were tested on a four module GeneXpert platform in each study site. Xpert HIV-1 VL testing was prioritized for patients who presented with advanced HIV disease, pregnant women, adolescents and suspected ART failures patients. On average, the study sites had a GeneXpert utilization rate of 50.4% (Gutu Mission Hospital), 63.5% (Murambinda Mission Hospital) and 17.5% (Chimombe Rural Health Centre) per month. GeneXpert polyvalent testing error rates remained lower than 4% in all sites. Decentralized EID and VL testing on Xpert had shorter overall median TAT (1 day [IQR: 0-4] and 1 day [IQR: 0-1] respectively) compared to centralized testing (17 days [IQR: 13-21] and 26 days [IQR: 23-32] respectively). Among patients with VL >1000 copies/ml (73/640; 11.4%) at GMH health facility, median time to enhanced adherence counselling was 8 days and majority of those with documented outcomes had re-suppressed VL (20/32; 62.5%). Median time to ART initiation among Xpert EID positive infants at GMH was 1 day [IQR: 0-1].

CONCLUSION

Implementation of near point-of-care GeneXpert platform for integrated multi-disease testing within district and sub-district healthcare settings is feasible and will increase access to VL, and EID testing to priority populations. Quality management systems including monitoring of performance indicators, together with regular on-site supervision are crucial, and near-POC test results must be promptly actioned-on by clinicians for patient management.

Sensitive Fluorescent Sensor for Recognition of HIV-1 dsDNA by Using Glucose Oxidase and Triplex DNA

A sensitive fluorescent sensor for sequence-specific recognition of double-stranded DNA (dsDNA) was developed on the surface of silver-coated glass slide (SCGS). Oligonucleotide-1 (Oligo-1) was designed to assemble on the surface of SCGS and act as capture DNA, and oligonucleotide-2 (Oligo-2) was designed as signal DNA. Upon addition of target HIV-1 dsDNA (Oligo-3•Oligo-4), signal DNA could bind on the surface of silver-coated glass because of the formation of C•GoC in parallel triplex DNA structure. Biotin-labeled glucose oxidase (biotin-GOx) could bind to signal DNA through the specific interaction of biotin-streptavidin, thereby GOx was attached to the surface of SCGS, which was dependent on the concentration of target HIV-1 dsDNA. GOx could catalyze the oxidation of glucose and yield H₂O₂, and the HPPA can be oxidized into a fluorescent product in the presence of HRP. Therefore, the concentration of target HIV-1 dsDNA could be estimated with fluorescence intensity. Under the optimum conditions, the fluorescence intensity was proportional to the concentration of target HIV-1 dsDNA over the range of 10 pM to 1000 pM, the detection limit was 3 pM. Moreover, the sensor had good sequence selectivity and practicability and might be applied for the diagnosis of HIV disease in the future.

Expansion of Viral Load Testing and the Potential Impact on Human Immunodeficiency Virus Drug Resistance

Increasing the volume, strengthening the quality, and proactively using data of human immunodeficiency virus (HIV) load testing are pivotal to limiting the threat of HIV drug resistance (HIVDR) accumulation,and allow for optimal case-based HIVDR surveillance. Triangulation of viral load (VL) and HIVDR testing data could be pursued to answer key questions and translate data and results for program and public policy. Identification of virologic failure and early management mitigates the greater risk of HIVDR. Routine VL monitoring and evaluation systems are necessary, and countries should consider reviewing system requirements, structural needs, and procedural and technical factors for the entire VL cascade, with special emphasis on post-test result use.

[Optimizing resources to reduce costs to determine HIV viral load in limited resources settings]

INTRODUCTION

HIV viral load testing is a key factor to evaluate the accomplishment of the UNAIDS target of 90% of viral suppression among people receiving antiretroviral therapy. Pooled samples are a potentially accurate and economic approach in resource-constrained settings, but efficiency can be negatively affected by high prevalence rates of virological failure.

OBJECTIVE

Strategies were assessed to increase the relative efficiency of pooled HIV viral load testing in resource-constrained settings.

MATERIALS AND METHODS

We evaluated two strategies: a) plasma samples were not included in pools if patients had <12 months on antiretroviral therapy, patients had previous viral load >1,000 copies/ml, or were antiretroviral therapy naïve patients, and b) plasma pools were organized separately for first and second-line antiretroviral therapy regimens. Individual viral load tests were used to compare pooled results.

RESULTS

Negative predictive values were similar for patients on first (100.0%; 95% CI 99.5 to 100.0) and second-line antiretroviral therapy regimens (99.4%; 95% CI 96.9 to 99.9). However, the incidence of virological failure among individuals on first-line antiretroviral therapy was lower than second-line antiretroviral therapy patients (p <0.01), resulting in greater savings in laboratory tests in patients on first-line antiretroviral therapy (74.0%; 95% CI 71.0 to 76.7) compared with the group of patients on second-line antiretroviral therapy (50.9%; 95% CI 44.4 to 57.3) (p<0.01).

CONCLUSION

Selecting the samples to be included in the pools and selecting the pools according to ART regimens are criteria that could lead to decreased spending on laboratory tests for HIV viral load determination in resource-constrained settings.

A pilot evaluation of whole blood finger-prick sampling for point-of-care HIV viral load measurement: the UNICORN study

There is a global need for HIV viral load point-of-care (PoC) assays to monitor patients receiving antiretroviral therapy. UNICORN was the first study of an off-label protocol using whole blood finger-prick samples tested with and without a simple three minute spin using a clinic-room microcentrifuge. Two PoC assays were evaluated in 40 HIV-positive participants, 20 with detectable and 20 with undetectable plasma viral load (pVL) (<20 copies/ml). Using 100 µl finger-prick blood samples, the Cepheid Xpert HIV-1 Viral Load and HIV-1 Qual cartridges were compared with laboratory pVL assessment (TaqMan, Roche). For participants with undetectable viraemia by TaqMan, there was poor concordance without centrifugation with the TaqMan platform with only 40% 'undetectable' using Xpert VL and 25% 'not detected' using the Qual assay. After a 3 minute spin, 100% of samples were undetectable using either assay, showing full concordance with the TaqMan assay. Defining a lower limit of detection of 1000 copies/ml when including a spin, there was 100% concordance with the TaqMan platform with strong correlation (rho 0.95 and 0.94; p < 0.0001 for both assays). When including a simple microcentrifugation step, finger-prick PoC testing was a quick and accurate approach for assessing HIV viraemia, with excellent concordance with validated laboratory approaches.

A Simple Phosphate-Buffered-Saline-Based Extraction Method Improves Specificity of HIV Viral Load Monitoring Using Dried Blood Spots

Although Roche COBAS Ampliprep/COBAS TaqMan (CAP/CTM) systems are widely used in sub-Saharan Africa for early infant diagnosis of HIV from dried blood spots (DBS), viral load monitoring with this system is not practical due to nonspecific extraction of both cell-free and cell-associated viral nucleic acids. A simplified DBS extraction technique for cell-free virus elution using phosphate-buffered saline (PBS) may provide an alternative analyte for lower-cost quantitative HIV virus load (VL) testing to monitor antiretroviral therapy (ART). We evaluated the CAP/CTM v2.0 assay in 272 paired plasma and DBS specimens using the cell-free virus elution method and determined the level of agreement, sensitivity, and specificity at thresholds of target not detected (TND), target below the limit of quantification (BLQ) (<20 copies/ml in plasma or <400 copies/ml in DBS), and VL of <1,000 copies/ml, and VL of <5,000 copies/ml. Reported plasma VL ranged from TND, or <20, to 5,781,592 copies/ml, and DBS VL ranged from TND, or <400, to 467,600 copies/ml. At <1000 copies/ml, agreement between DBS and plasma was 96.7% (kappa coefficient, 0.93; P < 0.0001). The mean difference between DBS and plasma VL values was -1.06 log10 copies/ml (95% confidence interval [CI], -1.17, -0.97; P < 0.0001). At a treatment failure threshold of >1,000 copies/ml, the sensitivities, specificities, positive predictive values (PPV), and negative predictive values (NPV) were 92.7%, 100%, 100%, and 94.3%, respectively. PBS elution of DBS offers a sensitive and specific method for monitoring plasma viremia among adults and children on ART at the WHO-recommended threshold of >1,000 copies/ml on the Roche CAP/CTM system.

Field Evaluation of Dried Blood Spots for HIV-1 Viral Load Monitoring in Adults and Children Receiving Antiretroviral Treatment in Kenya: Implications for Scale-up in Resource-Limited Settings

BACKGROUND

The World Health Organization recommends viral load (VL) as the preferred method for diagnosing antiretroviral therapy failure; however, operational challenges have hampered the implementation of VL monitoring in most resource-limited settings. This study evaluated the accuracy of dried blood spot (DBS) VL testing under field conditions as a practical alternative to plasma in determining virologic failure (VF).

METHODS

From May to December 2013, paired plasma and DBS specimens were collected from 416 adults and 377 children on antiretroviral therapy for ≥6 months at 12 clinics in Kenya. DBSs were prepared from venous blood (V-DBS) using disposable transfer pipettes and from finger-prick capillary blood using microcapillary tubes (M-DBS) and directly spotting (D-DBS). All samples were tested on the Abbott m2000 platform; V-DBS was also tested on the Roche COBAS Ampliprep/COBAS TaqMan (CAP/CTM) version 2.0 platform. VF results were compared at 3 DBS thresholds (≥1000, ≥3000, and ≥5000 copies/mL) and a constant plasma threshold of ≥1000 copies/mL.

RESULTS

On the Abbott platform, at ≥1000-copies/mL threshold, sensitivities, specificities, and kappa values for VF determination were ≥88.1%, ≥93.1%, and ≥0.82%, respectively, for all DBS methods, and it had the lowest percentage of downward misclassification compared with higher thresholds. V-DBS performance on CAP/CTM had significantly poorer specificity at all thresholds (1000%-33.0%, 3000%-60.9%, and 5000%-77.0%). No significant differences were found between adults and children.

CONCLUSIONS

VL results from V-DBS, M-DBS, and D-DBS were comparable with those from plasma for determining VF using the Abbott platform but not with CAP/CTM. A 1000-copies/mL threshold was optimal and should be considered for VF determination using DBS in adults and children.

Can Hepatitis C Virus Antigen Testing Replace Ribonucleic Acid Polymearse Chain Reaction Analysis for Detecting Hepatitis C Virus? A Systematic Review

The complexity and cost of current diagnostics for hepatitis C virus (HCV) may act as a prevention to the scale-up of treatment in the developing world. Currently, ribonucleic acid (RNA)-polymerase chain reaction tests are the gold standard. However, there is potential for the use of simpler and cheaper antigen tests to confirm HCV infection in different clinical settings. We evaluated the sensitivity and specificity of antigen assays. This was compared with the reference-standard RNA assays. A subanalysis also assessed Architect core antigen test, which is the only commercially available antigen test on the market. In 24 datasets, evaluating HCV-antigen assays in 8136 samples, the percentage of HCV-antigen positive, HCV-RNA negative was 0.57%. The percentage HCV-antigen negative, HCV-RNA positive was 3.52%. There is strong evidence that antigen detection performs as well as RNA-based assays for HCV management. The use of antigen tests could improve access to HCV care in underresourced healthcare settings.

Sequence specific recognition of HIV-1 dsDNA in the large amount of normal dsDNA based upon nicking enzyme signal amplification and triplex DNA

A sensitive fluorescent strategy for sequence specific recognition of HIV dsDNA was established based upon Nicking Enzyme Signal Amplification (NESA) and triplex formation. dsDNA sequence from the site 7960 to site 7991 of the HIV1 dsDNA gene was designed as target dsDNA, which was composed of two complementary strands Oligonucleotide 1 with the sequence of 3'-CTT CCT TAT CTT CTT CTT CCA CCT CTC TCT CT-5' (Oligo-1) and Oligonucleotide 2 with the sequence of 5'-GAA GGA ATA GAA GAA GAA GGT GGA GAG AGA GA-3' (Oligo-2). As a proof of concept, Oligonucleotide 5'-6-FAM-GAG GTG GAG CTG CGC GAC TCC TCC TCT CTC TCT CTC CAC CTC-BHQ-1-3'(Oligo-4) acted as molecular beacon(MB) probe, Oligonucleotide 5'-CTT CCT TAT CTT CTT CTT CCA AAA GGA GTC GCG-3' (Oligo-7) acted as assistant probe. In the presence of target dsDNA, Oligo-4 and Oligo-7 hybridized with target dsDNA through triplex formation and formed Y-shaped structure, NESA occurred with further addition of Nt.BbvCI, accompanied with the release of fluorescent DNA fragment circularly, resulted in the increase of fluorescence intensity. Under the optimum conditions, the fluorescence intensity was linear with the concentration of target dsDNA over the range from 100pM to 200nM, the linear regression equation was I = 1.266 C + 84.3 (C: nmol/L, R² = 0.991), with a detection limit of 65pM. Moreover, the effect of coexisted other dsDNA was investigated as well, and satisfactory results were obtained.

Specimen origin, type and testing laboratory are linked to longer turnaround times for HIV viral load testing in Malawi

Background

Efforts to reach UNAIDS’ treatment and viral suppression targets have increased demand for viral load (VL) testing and strained existing laboratory networks, affecting turnaround time. Longer VL turnaround times delay both initiation of formal adherence counseling and switches to second-line therapy for persons failing treatment and contribute to poorer health outcomes.

Methods

We utilized descriptive statistics and logistic regression to analyze VL testing data collected in Malawi between January 2013 and March 2016. The primary outcomes assessed were greater-than-median pretest phase turnaround time (days elapsed from specimen collection to receipt at the laboratory) and greater-than-median test phase turnaround time (days from receipt to testing).

Results

The median number of days between specimen collection and testing increased 3-fold between 2013 (8 days, interquartile range (IQR) = 6–16) and 2015 (24, IQR = 13–39) (p<0.001). Multivariable analysis indicated that the odds of longer pretest phase turnaround time were significantly higher for specimen collection districts without laboratories capable of conducting viral load tests (adjusted odds ratio (aOR) = 5.16; 95% confidence interval (CI) = 5.04–5.27) as well as for Malawi’s Northern and Southern regions. Longer test phase turnaround time was significantly associated with use of dried blood spots instead of plasma (aOR = 2.30; 95% CI = 2.23–2.37) and for certain testing months and testing laboratories.

Conclusion

Increased turnaround time for VL testing appeared to be driven in part by categorical factors specific to the phase of turnaround time assessed. Given the implications of longer turnaround time and the global effort to scale up VL testing, addressing these factors via increasing efficiencies, improving quality management systems and generally strengthening the VL spectrum should be considered essential components of controlling the HIV epidemic.

Comprehensiveness of HIV care provided at global HIV treatment sites in the IeDEA consortium: 2009 and 2014

INTRODUCTION

An important determinant of the effectiveness of HIV treatment programs is the capacity of sites to implement recommended services and identify systematic changes needed to ensure that invested resources translate into improved patient outcomes. We conducted a survey in 2014 of HIV care and treatment sites in the seven regions of the International epidemiologic Database to Evaluate AIDS (IeDEA) Consortium to evaluate facility characteristics, HIV prevention, care and treatment services provided, laboratory capacity, and trends in the comprehensiveness of care compared to data obtained in the 2009 baseline survey.

METHODS

Clinical staff from 262 treatment sites in 45 countries in IeDEA completed a site survey from September 2014 to January 2015, including Asia-Pacific with Australia (n = 50), Latin America and the Caribbean (n = 11), North America (n = 45), Central Africa (n = 17), East Africa (n = 36), Southern Africa (n = 87), and West Africa (n = 16). For the 55 sites with complete data from both the 2009 and 2014 survey, we evaluated change in comprehensiveness of care.

RESULTS

The majority of the 262 sites (61%) offered seven essential services (ART adherence, nutritional support, PMTCT, CD4+ cell count testing, tuberculosis screening, HIV prevention, and outreach). Sites that were publicly funded (64%), cared for adults and children (68%), low or middle Human Development Index (HDI) rank (68%, 68%), and received PEPFAR support (71%) were most often fully comprehensive. CD4+ cell count testing was universally available (98%) but only 62% of clinics offered it onsite. Approximately two-thirds (69%) of sites reported routine viral load testing (44-100%), with 39% having it onsite. Laboratory capacity to monitor antiretroviral-related toxicity and diagnose opportunistic infections varied widely by testing modality and region. In the subgroup of 55 sites with two surveys, comprehensiveness of services provided significantly increased across all regions from 2009 to 2014 (5.7 to 6.5, p < 0.001).

CONCLUSION

The availability of viral load monitoring remains suboptimal and should be a focus for site capacity, particularly in East and Southern Africa, where the majority of those initiating on ART reside. However, the comprehensiveness of care provided increased over the past 5 years and was related to type of funding received (publicly funded and PEPFAR supported).

Sensitivity and specificity of dried blood spots for HIV-1 viral load quantification: A laboratory assessment of 3 commercial assays

The use of dried blood spots (DBS) instead of plasma as a specimen type for HIV-1 viral load (VL) testing facilitates the decentralization of specimen collection and can increase access to VL testing in resource-limited settings. The performance of DBS for VL testing is lower, however, when compared to the gold standard sample type plasma. In this diagnostic accuracy study, we evaluated 3 VL assays with DBS.Participants were recruited between August 2012 and April 2015. Both plasma and DBS specimens were prepared and tested for HIV-1 VL with the Roche CAP/CTM HIV-1 test v2.0, the Abbott RealTime HIV-1, and the bioMérieux NucliSENS EasyQ HIV-1 v2.0. Sensitivity and specificity to detect treatment failure at a threshold of 1000 cps/mL with DBS were determined.A total of 272 HIV-positive patients and 51 HIV-negative people were recruited in the study. The mean difference or bias between plasma and DBS VL was <0.5 log cps/mL with all 3 assays but >25% of the specimens differed by >0.5 log cps/mL.All 3 assays had comparable sensitivities around 80% and specificities around 90%. Upward misclassification rates were around 10%, but downward misclassification rates ranged from 20.3% to 23.6%. Differences in between assays were not statistically significant (P > 0.1).The 3 VL assays evaluated had suboptimal performance with DBS but still performed better than immunological or clinical monitoring. Even after the introduction of the much-anticipated point-of-care VL devices, it is expected that DBS will remain important as a complementary option for supporting access to VL monitoring, particularly in rural, resource-limited settings. Manufacturers should accelerate efforts to develop more reliable, sensitive and specific methods to test VL on DBS specimens.

Confirmation of factors that influence antiretroviral regimen change and the subsequent patient outcomes at a Regional Hospital in rural KwaZulu-Natal

Background

Treatment failure (TF) and adverse drug reactions (ADRs) are the main indications for antiretroviral therapy (ART) regimen change. Identification of factors influencing regimen change and subsequent health outcomes of patients after regimen change is essential in providing a sustainable and effective antiretroviral roll-out campaign.

Aim

To confirm the factors that influence antiretroviral regimen change and to evaluate patient outcomes post regimen change.

Methods

A retrospective chart analysis of 269 HIV-infected non-pregnant patients (age >18 years), who underwent an antiretroviral (ARV) regimen change and were followed up for approximately one year since initiation, was undertaken at a Provincial Hospital ARV Clinic in KwaZulu-Natal, from January 2008 to December 2012.

Results

Of the 269 patients, there were 200 females (75%). Most patients were between the ages 30 and 44 (57.6%). Only five patients had coexisting tuberculosis (TB) infection (2%). The most common first-line ART regimen to be changed was stavudine (D4T)/lamivudine(3TC)/ efavirenz(EFV) n = 111(41%). The most common regimen patients were changed to was tenofovir (TDF)/3TC/EFV n = 89(33%). Stavudine was the most commonly substituted drug (35.5%). Lipodystrophy was the most common ADR (56.8%). ADR was the indication for ART regimen change in 175 patients (65%), whilst TF accounted for ART regimen change in 94 patients (35%). Immunological success (CD4 counts) was shown after regimen change (374.21 ± 243.16 vs. 456.09 ± 250.07, CI: 0.95, p < 0.001). Undetectable viral loads were measured in 172/205 (83.9%) patients post regimen change.

Conclusion

ADRs were the main cause for antiretroviral regimen change. Stavudine was the most substituted drug with lipodystrophy being the most common side effect. Coexisting TB infection did not influence regimen change. Immunological and virological success was shown after regimen modification.

Availability and Use of HIV Monitoring and Early Infant Diagnosis Technologies in WHO Member States in 2011-2013: Analysis of Annual Surveys at the Facility Level

BACKGROUND

The Joint United Nations Programme on HIV and AIDS (UNAIDS) 90-90-90 targets have reinforced the importance of functioning laboratory services to ensure prompt diagnosis and to assess treatment efficacy. We surveyed the availability and utilization of technologies for HIV treatment monitoring and early infant diagnosis (EID) in World Health Organization (WHO) Member States.

METHODS AND FINDINGS

The survey questionnaire included 14 structured questions focusing on HIV testing, cluster of differentiation 4 (CD4) testing, HIV viral load (VL) testing, and EID and was administered annually from 2012 to 2014 through WHO country offices, with each survey covering the previous 12-mo period. Across 127 targeted countries, survey response rates were 60% in 2012, 67% in 2013, and 78% in 2014. There were encouraging trends towards increased procurement of CD4 and VL/EID instruments in reporting countries. Globally, the capacity of available CD4 instruments was sufficient to meet the demand of all people living with HIV/AIDS (PLWHA), irrespective of treatment status (4.62 theoretical tests per PLWHA in 2013 [median 7.33; interquartile range (IQR) 3.44-17.75; median absolute deviation (MAD) 4.35]). The capacity of VL instruments was inadequate to cover all PLWHA in many reporting countries (0.44 tests per PLWHA in 2013 [median 0.90; IQR 0.30-2.40; MAD 0.74]). Of concern, only 13.7% of existing CD4 capacity (median 4.3%; IQR 1.1%-12.1%; MAD 3.8%) and only 36.5% of existing VL capacity (median 9.4%; IQR 2.3%-28.9%; MAD 8.2%) was being utilized across reporting countries in 2013. By the end of 2013, 7.4% of all CD4 instruments (5.8% CD4 conventional instruments and 11.0% of CD4 point of care [POC]) and 10% of VL/EID instruments were reportedly not in use because of lack of reagents, the equipment not being installed or deployed, maintenance, and staff training requirements. Major limitations of this survey included under-reporting and/or incomplete reporting in some national programmes and noncoverage of the private sector.

CONCLUSION

This is the first attempt to comprehensively gather information on HIV testing technology coverage in WHO Member States. The survey results suggest that major operational changes will need to be implemented, particularly in low- and middle-income countries, if the 90-90-90 targets are to be met.

Brief Report: Virologic Monitoring Can Be a Cost-Effective Strategy to Diagnose Treatment Failure on First-Line ART

Supplemental Digital Content is Available in the Text.

CD4 count testing is perceived to be an affordable strategy to diagnose treatment failure on first-line antiretroviral therapy. We hypothesize that the superior accuracy of viral load (VL) testing will result in less patients being incorrectly switched to more expensive and toxic second-line regimens. Using data from a drug resistance cohort, we show that CD4 testing is approximately double the cost to make 1 correct regimen switch under certain diagnostic thresholds (CD4 = US $499 vs. VL = US $186 or CD4 = US $3031 vs. VL = US $1828). In line with World Health Organization guidelines, our findings show that VL testing can be both an accurate and cost-effective treatment monitoring strategy.

HIV viral suppression in TREAT Asia HIV Observational Database enrolled adults on antiretroviral therapy at the Social Health Clinic, the National Center for HIV/AIDS, Dermatology & STDs, Phnom Penh, Cambodia

BACKGROUND

The Social Health Clinic at the National Center for HIV/AIDS, Dermatology & STDs (SHC-NCHADS) in Phnom Penh is a major provider of antiretroviral therapy (ART) in Cambodia. However, patient access to viral load monitoring is uncommon. We conducted a cross-sectional evaluation of HIV viral load in SHC-NCHADS patients on ART to determine the proportion experiencing virological failure and to identify factors associated with virological failure in this population.

METHODS

Patients who had been using their current first- or second-line ART regimen for ≥6 months were eligible. Virological failure was defined as a viral load >1,000 copies/ml, death, lost-to-follow-up or the absence of viral load testing despite presenting for care. Factors associated with virological failure were evaluated using logistic regression.

RESULTS

Overall, 463 patients (53.1% male, median age 42.1 years) were included in the investigation. At the time of current regimen initiation, median CD4⁺ T-cell count was 101 cells/mm³ and 89.0% of patients had experienced a WHO stage III/IV event. At the time of testing/last clinic visit, 28 (6.0%) patients met our definition of virological failure. Median viral load among those failing was 9,633 copies/ml. Shorter time on current ART regimen, low CD4⁺ T-cell count at the time of viral load testing/last clinic visit and a record of suboptimal adherence were the strongest predictors of virological failure.

CONCLUSIONS

This work demonstrates the high rate of viral suppression being achieved by the treatment programme at SHC-NCHADS and the need for future work to phase-in routine viral load monitoring in Cambodia.

Evaluating facility-based antiretroviral therapy programme effectiveness: a pilot study comparing viral load suppression and retention rates

OBJECTIVES

Increased demand for antiretroviral therapy (ART) services combined with plateaued levels of development assistance for HIV/AIDS requires that national ART programmes monitor programme effectiveness. In this pilot study, we compared commonly utilised performance metrics of 12- and 24-month retention with rates of viral load (VL) suppression at 15 health facilities in Uganda.

METHODS

Retrospective chart review from which 12- and 24-month retention rates were estimated, and parallel HIV RNA VL testing on consecutive adult patients who presented to clinics and had been on ART for a minimum of six months. Rates of VL suppression were then calculated at each facility and compared to retention rates to assess the correlation between performance metrics. Multilevel logistic regression models predicting VL suppression and 12- and 24-month retention were constructed to estimate facility effects.

RESULTS

We collected VL samples from 2961 patients and found that 88% had a VL ≤1000 copies/ml. Facility rates of VL suppression varied between 77% and 96%. When controlling for patient mix, a significant variation in facility performance persisted. Retention rates at 12 and 24 months were 91% and 79%, respectively, with a comparable facility-level variation. However, neither 12-month (ρ = 0.16) nor 24-month (ρ = -0.19) retention rates were correlated with facility rates of VL suppression.

CONCLUSIONS

Retaining patients in care and suppressing VL are both critical outcomes. Given the lack of correlation noted in this study, the utilisation of VL monitoring may be necessary to truly assess the effectiveness of health facilities delivering ART services.

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.

Projecting the epidemiological effect, cost-effectiveness and transmission of HIV drug resistance in Vietnam associated with viral load monitoring strategies

OBJECTIVES

The objective of this study was to investigate the potential epidemiological impact of viral load (VL) monitoring and its cost-effectiveness in Vietnam, where transmitted HIV drug resistance (TDR) prevalence has increased from <5% to 5%-15% in the past decade.

METHODS

Using a population-based mathematical model driven by data from Vietnam, we simulated scenarios of various combinations of VL testing coverage, VL thresholds for second-line ART initiation and availability of HIV drug-resistance tests. We assessed the cost per disability-adjusted life year (DALY) averted for each scenario.

RESULTS

Projecting expected ART scale-up levels, to approximately double the number of people on ART by 2030, will lead to an estimated 18 510 cases (95% CI: 9120-34 600 cases) of TDR and 55 180 cases (95% CI: 40 540-65 900 cases) of acquired drug resistance (ADR) in the absence of VL monitoring. This projection corresponds to a TDR prevalence of 16% (95% CI: 11%-24%) and ADR of 18% (95% CI: 15%-20%). Annual or biennial VL monitoring with 30% coverage is expected to relieve 12%-31% of TDR (2260-5860 cases), 25%-59% of ADR (9620-22 650 cases), 2%-6% of HIV-related deaths (360-880 cases) and 19 270-51 400 DALYs during 2015-30. The 30% coverage of VL monitoring is estimated to cost US$4848-5154 per DALY averted. The projected additional cost for implementing this strategy is US$105-268 million over 2015-30.

CONCLUSIONS

Our study suggests that a programmatically achievable 30% coverage of VL monitoring can have considerable benefits for individuals and leads to population health benefits by reducing the overall national burden of HIV drug resistance. It is marginally cost-effective according to common willingness-to-pay thresholds.

Viral load monitoring and antiretroviral treatment outcomes in a pediatric HIV cohort in Ghana

Background

HIV-infected children in sub-Saharan Africa may be at a high risk of staying on a failing first-line regimen and developing drug-resistance HIV variants due to lack of routine viral load monitoring. We investigated whether cumulative viral load, measured as viremia copy-years (VCY) could predict morbidity in a setting where viral load is not routinely monitored.

Methods

This was a single-center prospective observational longitudinal study of HIV-infected children initiating antiretroviral therapy (ART) at the Pediatric HIV/AIDS Care program at Korle-Bu Teaching Hospital in Accra, Ghana. The main outcome was morbidity measured as frequency of hospitalizations, opportunistic infections, and outpatient sick visits. The main explanatory variable was viral load measured as VCY.

Results

The study included 140 children who initiated ART between September 2009 and May 2013 and had at least 2 viral load measurements. There were 184 hospitalizations, with pneumonia being the most common cause (22.8 %). A total of 102 opportunistic infections was documented, with tuberculosis being the most common opportunistic infection (68 %). A total of 823 outpatient sick visits was documented, with upper respiratory infections (14.2 %) being the most common cause. Forty-four percent of our study participants had >4 log₁₀ VCY. Children in this sub-cohort had a higher frequency of sick visits compared with those with <4 log₁₀ VCY (p = 0.03). Only 6.5 % of children with >4 log₁₀ VCY had been identified as treatment failure using WHO clinical and immunological treatment failure criteria.

Conclusions

High level of cumulative viral load may translate to virological failure and subsequent increased all-cause morbidity. Our finding of potential utility of VCY in pediatrics warrants further investigations. VCY may be a good alternate to routine viral load measurement as its determination may be less frequent and could be personalized to save cost.

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.

Efavirenz-Based Antiretroviral Therapy Among Nevirapine-Exposed HIV-Infected Children in South Africa: A Randomized Clinical Trial

IMPORTANCE

Advantages of using efavirenz as part of treatment for children infected with human immunodeficiency virus (HIV) include once-daily dosing, simplification of co-treatment for tuberculosis, preservation of ritonavir-boosted lopinavir for second-line treatment, and harmonization of adult and pediatric treatment regimens. However, there have been concerns about possible reduced viral efficacy of efavirenz in children exposed to nevirapine for prevention of mother-to-child transmission.

OBJECTIVE

To evaluate whether nevirapine-exposed children achieving initial viral suppression with ritonavir-boosted lopinavir-based therapy can transition to efavirenz-based therapy without risk of viral failure.

DESIGN, SETTING, AND PARTICIPANTS

Randomized, open-label noninferiority trial conducted at Rahima Moosa Mother and Child Hospital, Johannesburg, South Africa, from June 2010 to December 2013, enrolling 300 HIV-infected children exposed to nevirapine for prevention of mother-to-child transmission who were aged 3 years or older and had plasma HIV RNA of less than 50 copies/mL during ritonavir-boosted lopinavir-based therapy; 298 were randomized and 292 (98%) were followed up to 48 weeks after randomization.

INTERVENTIONS

Participants were randomly assigned to switch to efavirenz-based therapy (n = 150) or continue ritonavir-boosted lopinavir-based therapy (n = 148).

MAIN OUTCOMES AND MEASURES

Risk difference between groups in (1) viral rebound (ie, ≥1 HIV RNA measurement of >50 copies/mL) and (2) viral failure (ie, confirmed HIV RNA >1000 copies/mL) with a noninferiority bound of -0.10. Immunologic and clinical responses were secondary end points.

RESULTS

The Kaplan-Meier probability of viral rebound by 48 weeks was 0.176 (n = 26) in the efavirenz group and 0.284 (n = 42) in the ritonavir-boosted lopinavir group. Probabilities of viral failure were 0.027 (n = 4) in the efavirenz group and 0.020 (n = 3) in the ritonavir-boosted lopinavir group. The risk difference for viral rebound was 0.107 (1-sided 95% CI, 0.028 to ∞) and for viral failure was -0.007 (1-sided 95% CI, -0.036 to ∞). We rejected the null hypothesis that efavirenz is inferior to ritonavir-boosted lopinavir (P < .001) for both end points. By 48 weeks, CD4 cell percentage was 2.88% (95% CI, 1.26%-4.49%) higher in the efavirenz group than in the ritonavir-boosted lopinavir group.

CONCLUSIONS AND RELEVANCE

Among HIV-infected children exposed to nevirapine for prevention of mother-to-child transmission and with initial viral suppression with ritonavir-boosted lopinavir-based therapy, switching to efavirenz-based therapy compared with continuing ritonavir-boosted lopinavir-based therapy did not result in significantly higher rates of viral rebound or viral failure. This therapeutic approach may offer advantages in children such as these.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT01146873.

On the front line of HIV virological monitoring: barriers and facilitators from a provider perspective in resource-limited settings

Scale-up of viral load (VL) monitoring for HIV-infected patients on antiretroviral therapy (ART) is a priority in many resource-limited settings, and ART providers are critical to effective program implementation. We explored provider-perceived barriers and facilitators of VL monitoring. We interviewed all providers (n = 17) engaged in a public health evaluation of dried blood spots for VL monitoring at five ART clinics in Malawi. All ART clinics were housed within district hospitals. We grouped themes at patient, provider, facility, system, and policy levels. Providers emphasized their desire for improved ART monitoring strategies, and frustration in response to restrictive policies for determining which patients were eligible to receive VL monitoring. Although many providers pled for expansion of monitoring to include all persons on ART, regardless of time on ART, the most salient provider-perceived barrier to VL monitoring implementation was the pressure of work associated with monitoring activities. The work burden was exacerbated by inefficient data management systems, highlighting a critical interaction between provider-, facility-, and system-level factors. Lack of integration between laboratory and clinical systems complicated the process for alerting providers when results were available, and these communication gaps were intensified by poor facility connectivity. Centralized second-line ART distribution was also noted as a barrier: providers reported that the time and expenses required for patients to collect second-line ART frequently obstructed referral. However, provider empowerment emerged as an unexpected facilitator of VL monitoring. For many providers, this was the first time they used an objective marker of ART response to guide clinical management. Providers' knowledge of a patient's virological status increased confidence in adherence counseling and clinical decision-making. Results from our study provide unique insight into provider perceptions of VL monitoring and indicate the importance of policies responsive to individual and environmental challenges of VL monitoring program implementation. Findings may inform scale-up by helping policy-makers identify strategies to improve feasibility and sustainability of VL monitoring.

Combination Antiretroviral Therapy for HIV in Rwandan Adults: Clinical Outcomes and Impact on Reproductive Health up to 24 Months

Adult women (n = 113) and men (n = 100) initiating combination antiretroviral therapy (cART) and women not yet eligible for cART (n = 199) in Kigali, Rwanda, were followed for 6–24 months between 2007 and 2010. In the cART groups, 21% of patients required a drug change due to side effects and 11% of patients had virological failure (defined as >1,000 HIV RNA copies/mL) after 12 months of cART. About a third of the pregnancies since HIV diagnosis were unintended. The proportion of women in the pre-cART group using modern contraception other than condoms (50%) was similar to women in the general population, but this proportion was only 25% in women initiating cART. Of the women who carried at least one pregnancy to term since having been diagnosed HIV-positive, a third reported to have participated in a prevention-of-mother-to-child-transmission (PMTCT, option A) intervention. Many patients were coinfected with herpes simplex virus type 2 (79–92%), human papillomavirus (38–53%), and bacterial sexually transmitted infections (STIs) with no differences between groups. We applaud the Rwandan government for having strengthened family planning and PMTCT services and for having introduced HPV vaccination in recent years, but additional work is needed to strengthen STI and HPV-related cancer screening and management in the HIV-positive population.

Plasma viraemia in HIV-positive pregnant women entering antenatal care in South Africa

Introduction

Plasma HIV viral load (VL) is the principle determinant of mother-to-child HIV transmission (MTCT), yet there are few data on VL in populations of pregnant women in sub-Saharan Africa. We examined the distribution and determinants of VL in HIV-positive women seeking antenatal care (ANC) in Cape Town, South Africa.

Methods

Consecutive HIV-positive pregnant women making their first antenatal clinic visit were recruited into a cross-sectional study of viraemia in pregnancy, including a brief questionnaire and specimens for VL testing and CD4 cell enumeration.

Results & discussion

Overall 5551 pregnant women sought ANC during the study period, of whom 1839 (33%) were HIV positive and 1521 (85%) were included. Approximately two-thirds of HIV-positive women in the sample (n=947) were not on antiretrovirals at the time of the first ANC visit, and the remainder (38%, n=574) had initiated antiretroviral therapy (ART) prior to conception. For women not on ART, the median VL was 3.98 log₁₀ copies/mL; in this group, the sensitivity of CD4 cell counts ≤350 cells/µL in detecting VL>10,000 copies/mL was 64% and this increased to 78% with a CD4 threshold of ≤500 cells/µL. Among women on ART, 78% had VL<50 copies/mL and 13% had VL >1000 copies/mL at the time of their ANC visit.

Conclusions

VL >10,000 copies/mL was commonly observed in women not on ART with CD4 cell counts >350 cells/µL, suggesting that CD4 cell counts may not be adequately sensitive in identifying women at greatest risk of MTCT. A large proportion of women entering ANC initiated ART before conception, and in this group more than 10% had VL>1000 copies/mL despite ART use. VL monitoring during pregnancy may help to identify pregnancies that require additional clinical attention to minimize MTCT risk and improve maternal and child health outcomes.

HIV-1 variability and viral load technique could lead to false positive HIV-1 detection and to erroneous viral quantification in infected specimens

OBJECTIVES

Viral load (VL) testing is used for early HIV diagnosis in infants (EID) and for detecting early therapeutic failure events, but can be affected by HIV genetic variability. Dried blood samples (DBS) increase VL access and EID in remote settings and when low blood volume is available.

METHODS

This study compares VL values using Siemens VERSANT HIV-1 RNA 1.0 kPCR assay (kPCR) and Roche CAP/CTM Quantitative test v2.0 (CAP/CTM v2.0) in 176 DBS carrying different HIV-1 variants collected from 69 Equatoguinean mothers and their infants with known HIV-1 status (71 infected, 105 uninfected).

RESULTS

CAP/CTM v2.0 provided false positive VLs in 11 (10.5%) cases. VL differences above 0.5 log10 were observed in 42/49 (87.5%) DBS, and were above 1 log10 in 18 cases. CAP/CTM v2.0 quantified all the 41 specimens with previously inferred HIV-1 variant by phylogenetic analysis (68.3% recombinants) whereas kPCR only identified 90.2% of them, and was unable to detect 14.3% of 21 CRF02_AG viruses. CAP/CTM v2.0 showed higher sensitivity than kPCR (95.8% vs. 70.1%), quantifying a higher rate of viruses in infected DBS from subjects under antiretroviral exposure at sampling time compared to kPCR (94.7% vs. 96.2%, p-value<0.001). kPCR showed maximum specificity (100%) whereas for CAP/CTM v2.0 was 89.5%.

CONCLUSIONS

VL assays should increase their sensitivity and specificity to avoid overestimated HIV-1 quantifications, which could be interpreted as virological failure events, or false negative diagnostic results due to genetic variability. We recommend using the same VL technique for each patient during antiretroviral therapy monitoring.