Role of viral suppression in HIV treatment and prevention and its potential in addressing harmful laws and discrimination.

The World Health Organization's (WHO) global public health mandate includes a focus on expanding access to HIV testing, antiretroviral therapy (ART) and treatment monitoring to improve the clinical management of HIV, achieve sustained viral suppression, and prevent HIV-related incidence, morbidity, and mortality. This article documents key moments in research and WHO policies that have informed how ART is applied within HIV programs, including as a prevention tool with the potential to support efforts to address HIV-related discrimination. For more than 20years, WHO has promoted the benefits of HIV treatment including as part of the approach to prevent the mother-to-child transmission (vertical transmission) of HIV. WHO guidance has followed, and continues to follow, the evolving evidence. In 2023, WHO continues to clarify that there is zero risk of sexual HIV transmission when a person living with HIV has an undetectable viral load and an almost zero or negligible risk of sexual transmission when a person living with HIV has a viral load of ≤1000copies/mL - helping to evolve the focus of community campaigns and health worker training to include a focus on 'virally suppressed' while also continuing to emphasise the ultimate goal of achieving an undetectable viral load. This evolution does two things: first, it strongly reasserts the evidence around there being no chance of transmission if a person has an undetectable viral load; and second, it provides an extremely strong degree of confidence that, similarly, individuals who are virally suppressed will not pass on the virus sexually. WHO is now encouraging positive and clear messaging to highlight that the consistent use of ART prevents onwards HIV transmission.

The risk of sexual transmission of HIV in individuals with low-level HIV viraemia: a systematic review.

BACKGROUND: The risk of sexual transmission of HIV from individuals with low-level HIV viraemia receiving antiretroviral therapy (ART) has important public health implications, especially in resource-limited settings that use alternatives to plasma-based viral load testing. This Article summarises the evidence related to sexual transmission of HIV at varying HIV viral load levels to inform messaging for people living with HIV, their partners, their health-care providers, and the wider public. METHODS: We conducted a systematic review and searched PubMed, MEDLINE, Cochrane Central Register of Controlled Trials, Embase, Conference Proceedings Citation Index-Science, and WHO Global Index Medicus, for work published from Jan 1, 2010 to Nov 17, 2022. Studies were included if they pertained to sexual transmission between serodiscordant couples at various levels of viraemia, the science behind undetectable=untransmittable, or the public health impact of low-level viraemia. Studies were excluded if they did not specify viral load thresholds or a definition for low-level viraemia or did not provide quantitative viral load information for transmission outcomes. Reviews, non-research letters, commentaries, and editorials were excluded. Risk of bias was evaluated using the ROBINS-I framework. Data were extracted and summarised with a focus on HIV sexual transmission at varying HIV viral loads. FINDINGS: 244 studies were identified and eight were included in the analysis, comprising 7762 serodiscordant couples across 25 countries. The certainty of evidence was moderate; the risk of bias was low. Three studies showed no HIV transmission when the partner living with HIV had a viral load less than 200 copies per mL. Across the remaining four prospective studies, there were 323 transmission events; none were in patients considered stably suppressed on ART. Among all studies there were two cases of transmission when the index patient's (ie, patient with previously diagnosed HIV infection) most recent viral load was less than 1000 copies per mL. However, interpretation of both cases was complicated by long intervals (ie, 50 days and 53 days) between the transmission date and the most recent index viral load result. INTERPRETATION: There is almost zero risk of sexual transmission of HIV with viral loads of less than 1000 copies per mL. These data provide a powerful opportunity to destigmatise HIV and promote adherence to ART through dissemination of this positive public health message. These findings can also promote access to viral load testing in resource-limited settings for all people living with HIV by facilitating uptake of alternative sample types and technologies. FUNDING: Bill & Melinda Gates Foundation.

Cost-effectiveness of point-of-care versus centralised, laboratory-based nucleic acid testing for diagnosis of HIV in infants: a systematic review of modelling studies.

BACKGROUND: Point-of-care (POC) nucleic acid testing for diagnosis of HIV in infants facilitates earlier initiation of antiretroviral therapy (ART) than with centralised (standard-of-care, SOC) testing, but can be more expensive. We evaluated cost-effectiveness data from mathematical models comparing POC with SOC to provide global policy guidance. METHODS: In this systematic review of modelling studies, we searched PubMed, MEDLINE, Embase, the National Health Service Economic Evaluation Database, Econlit, and conference abstracts, combining terms for "HIV" + "infant"/"early infant diagnosis" + "point-of-care" + "cost-effectiveness" + "mathematical models", without restrictions from database inception to July 15, 2022. We selected reports of mathematical cost-effectiveness models comparing POC with SOC for HIV diagnosis in infants younger than 18 months. Titles and abstracts were independently reviewed, with full-text review for qualifying articles. We extracted data on health and economic outcomes and incremental cost-effectiveness ratios (ICERs) for narrative synthesis. The primary outcomes of interest were ICERs (comparing POC with SOC) for ART initiation and survival of children living with HIV. FINDINGS: Our search identified 75 records through database search. 13 duplicates were excluded, leaving 62 non-duplicate articles. 57 records were excluded and five were reviewed in full text. One article was excluded as it was not a modelling study, and four qualifying studies were included in the review. These four reports were from two mathematical models from two independent modelling groups. Two reports used the Johns Hopkins model to compare POC with SOC for repeat early infant diagnosis testing in the first 6 months in sub-Saharan Africa (first report, simulation of 25 000 children) and Zambia (second report, simulation of 7500 children). In the base scenario, POC versus SOC increased probability of ART initiation within 60 days of testing from 19% to 82% (ICER per additional ART initiation range US$430-1097; 9-month cost horizon) in the first report; and from 28% to 81% in the second ($23-1609, 5-year cost horizon). Two reports compared POC with SOC for testing at 6 weeks in Zimbabwe using the Cost-Effectiveness of Preventing AIDS Complications-Paediatric model (simulation of 30 million children; lifetime horizon). POC increased life expectancy and was considered cost-effective compared with SOC (ICER $711-850 per year of life saved in HIV-exposed children). Results were robust throughout sensitivity and scenario analyses. In most scenarios, platform cost-sharing (co-use with other programmes) resulted in POC being cost-saving compared with SOC. INTERPRETATION: Four reports from two different models suggest that POC is a cost-effective and potentially cost-saving strategy for upscaling of early infant testing compared with SOC. FUNDING: Bill & Melinda Gates Foundation, Unitaid, National Institute of Allergy and Infectious Diseases, National Institute of Child Health and Human Development, WHO, and Massachusetts General Hospital Research Scholars.

The clinical effect of point-of-care HIV diagnosis in infants: a systematic review and meta-analysis.

BACKGROUND: Timely diagnosis and treatment of HIV is crucial in HIV-exposed infants to prevent the high rates of mortality seen during the first 2 years of life if HIV is untreated. However, challenges with sample transportation, testing, and result delivery to caregivers have led to long delays in treatment initiation. We aimed to compare the clinical effect of point-of-care HIV testing versus laboratory-based testing (standard of care) in HIV-exposed infants. METHODS: We did a systematic review and meta-analysis and searched PubMed, MEDLINE, Cochrane Central Register of Controlled Trials, Embase, Conference Proceedings Citation Index-Science, and WHO Global Index Medicus, from Jan 1, 2014, to Aug 31, 2020. Studies were included if they pertained to the use of point-of-care nucleic acid testing for infant HIV diagnosis, had a laboratory-based nucleic acid test as the comparator or standard of care against the index test (same-day point-of-care testing), evaluated clinical outcomes when point-of-care testing was used, and included HIV-exposed infants aged younger than 2 years. Studies were excluded if they did not use a laboratory-based comparator, a nucleic acid test that had been approved by a stringent regulatory authority, or diagnostic-accuracy or performance evaluations (eg, no clinical outcomes included). Reviews, non-research letters, commentaries, and editorials were also excluded. The risk of bias was evaluated using the ROBINS-I framework. Data were extracted from published reports. Data from all studies were analysed using frequency statistics to describe the overall populations evaluated and their results. Key outcomes were time to result delivery and antiretroviral therapy initiation, and proportion of HIV-positive infants initiated on antiretroviral therapy within 60 days after sample collection. FINDINGS: 164 studies were identified by the search and seven were included in the analysis, comprising 37 377 infants in total across 15 countries, including 25 170 (67%) who had point-of-care HIV testing and 12 207 (33%) who had standard-of-care testing. The certainty of evidence was high. Same-day point-of-care testing led to a significantly shorter time between sample collection and result delivery to caregivers compared with standard-of-care testing (median 0 days [95% CI 0-0] vs 35 days [35-37]). Time from sample collection to antiretroviral therapy initiation in infants found to be HIV-positive was significantly lower with point-of-care testing compared with standard of care (median 0 days [95% CI 0-1] vs 40 days [36-44]). When each study's result was weighted equally, 90·3% (95% CI 76·7-96·5) of HIV-positive infants diagnosed using point-of-care testing had started antiretroviral therapy within 60 days of sample collection, compared with only 51·6% (27·1-75·7) who had standard-of-care testing (odds ratio 8·74 [95% CI 6·6-11·6]; p<0·0001). INTERPRETATION: Overall, the certainty of the evidence in this analysis was rated as high for the primary outcomes related to result delivery and treatment initiation, with no serious risk of bias, inconsistency, indirectness, or imprecision. In HIV-exposed infants, same-day point-of-care HIV testing was associated with significantly improved time to result delivery, time to antiretroviral therapy initiation, and proportion of HIV-positive infants starting antiretroviral therapy within 60 days compared with standard of care. FUNDING: The Bill & Melinda Gates Foundation.

Same-day test and treat for infants with HIV infection: finally within reach

In 2021, there were more than 150,000 new HIV infections among children; however, only 52% of children living with HIV were on antiretroviral treatment (ART) [1]. Untreated infants and young children are at high risk for rapid disease progression and death [2, 3]; early diagnosis and rapid treatment can prevent these outcomes [3]. In 2021, however, less than 65% of HIV-exposed infants received an infant test within the first 2 months of age [1]. The median time between sample collection to the results being received at the clinic was over 40 days in a recent systematic review of laboratorybased, standard-of-care infant testing in low- and middleincome countries [4]. Further, 15% of infants were known to have died during the prolonged lag time between testing and ART initiation. Fortunately, HIV nucleic acid tests for infant diagnosis that can be performed closer to the patient and provide results on the same day of sample collection are now available and have been approved by regulatory authorities [5]. In 2016, WHO conditionally recommended the use of point-of-care technologies for infant diagnosis [6], a recommendation then based on low-certainty evidence from only two diagnostic accuracy studies. Since then, there have been new data supporting the diagnostic accuracy of these tests and the clinical benefit when results are provided on the same day with linkage to immediate action­a rapid HIV test and treat approach for infants. A systematic review of 12 studies found the diagnostic accuracy of point-of-care technologies was greater than 98% sensitive and 99% specific [7]. In addition, a recent systematic review on the clinical impact of point-of-care testing identified seven studies that included 37,000 infants across 15 countries in sub-Saharan Africa. This study demonstrated that same-day point-of-care testing significantly reduced the time from sample collection to result delivery to caregivers compared to laboratory-based testing from 35 days (95% confidence interval [CI]: 35­37) to 0 days (95% CI: 0­0) and from sample collection to ART initiation among infants testing positive from 39.5 days (95% CI: 36­44) to 0 days (95% CI: 0­1) [8]. The overall proportion of infants living with HIV initiating ART within 60 days was 90% (95% CI: 77­97) when tested at the point of care compared to 52% (95% CI: 27­76) when tested using laboratory-based assays. Infants living with HIV tested using same-day point-of-care...

The performance of using dried blood spot specimens for HIV-1 viral load testing: A systematic review and meta-analysis.

BACKGROUND: Accurate routine HIV viral load testing is essential for assessing the efficacy of antiretroviral treatment (ART) regimens and the emergence of drug resistance. While the use of plasma specimens is the standard for viral load testing, its use is restricted by the limited ambient temperature stability of viral load biomarkers in whole blood and plasma during storage and transportation and the limited cold chain available between many health care facilities in resource-limited settings. Alternative specimen types and technologies, such as dried blood spots, may address these issues and increase access to viral load testing; however, their technical performance is unclear. To address this, we conducted a meta-analysis comparing viral load results from paired dried blood spot and plasma specimens analyzed with commonly used viral load testing technologies. METHODS AND FINDINGS: Standard databases, conferences, and gray literature were searched in 2013 and 2018. Nearly all studies identified (60) were conducted between 2007 and 2018. Data from 40 of the 60 studies were included in the meta-analysis, which accounted for a total of 10,871 paired dried blood spot:plasma data points. We used random effects models to determine the bias, accuracy, precision, and misclassification for each viral load technology and to account for between-study variation. Dried blood spot specimens produced consistently higher mean viral loads across all technologies when compared to plasma specimens. However, when used to identify treatment failure, each technology compared best to plasma at a threshold of 1,000 copies/ml, the present World Health Organization recommended treatment failure threshold. Some heterogeneity existed between technologies; however, 5 technologies had a sensitivity greater than 95%. Furthermore, 5 technologies had a specificity greater than 85% yet 2 technologies had a specificity less than 60% using a treatment failure threshold of 1,000 copies/ml. The study's main limitation was the direct applicability of findings as nearly all studies to date used dried blood spot samples prepared in laboratories using precision pipetting that resulted in consistent input volumes. CONCLUSIONS: This analysis provides evidence to support the implementation and scale-up of dried blood spot specimens for viral load testing using the same 1,000 copies/ml treatment failure threshold as used with plasma specimens. This may support improved access to viral load testing in resource-limited settings lacking the required infrastructure and cold chain storage for testing with plasma specimens.

Integrated use of laboratory services for multiple infectious diseases in the WHO European Region during the COVID-19 pandemic and beyond.

Technical advances in diagnostic techniques have permitted the possibility of multi-disease-based approaches for diagnosis and treatment monitoring of several infectious diseases, including tuberculosis (TB), human immunodeficiency virus (HIV), viral hepatitis and sexually transmitted infections (STI). However, in many countries, diagnosis and monitoring, as well as disease response programs, still operate as vertical systems, potentially causing delay in diagnosis and burden to patients and preventing the optimal use of available resources. With countries facing both human and financial resource constraints, during the COVID-19 pandemic even more than before, it is important that available resources are used as efficiently as possible, potential synergies are leveraged to maximise benefit for patients, continued provision of essential health services is ensured. For the infectious diseases, TB, HIV, hepatitis C (HCV) and STI, sharing devices and integrated services starting with rapid, quality-assured, and complete diagnostic services is beneficial for the continued development of adequate, efficient and effective treatment strategies. Here we explore the current and future potential (as well as some concerns), importance, implications and necessary implementation steps for the use of platforms for multi-disease testing for TB, HIV, HCV, STI and potentially other infectious diseases, including emerging pathogens, using the example of the COVID-19 pandemic.

HIV viral load assays when used with whole blood perform well as a diagnostic assay for infants.

OBJECTIVE: Over the past several years, only approximately 50% of HIV-exposed infants received an early infant diagnosis test within the first two months of life. While high attrition and mortality account for some of the shortcomings in identifying HIV-infected infants early and putting them on life-saving treatment, fragmented and challenging laboratory systems are an added barrier. We sought to determine the accuracy of using HIV viral load assays for infant diagnosis of HIV. METHODS: We enrolled 866 Ugandan infants between March-April 2018 for this study after initial laboratory diagnosis. The median age was seven months, while 33% of infants were less than three months of age. Study testing was done using either the Roche or Abbott molecular technologies at the Central Public Health Laboratory. Dried blood spot samples were prepared according to manufacturer-recommended protocols for both the qualitative and quantitative assays. Viral load test samples for the Roche assay were processed using two different buffers: phosphate-buffered saline (PBS: free virus elution viral load protocol [FVE]) and Sample Pre-Extraction Reagent (SPEX: qualitative buffer). Dried blood spot samples were processed for both assays on the Abbott using the manufacturer's standard infant diagnosis protocol. All infants received a qualitative test for clinical management and additional paired quantitative tests. RESULTS: 858 infants were included in the analysis, of which 50% were female. Over 75% of mothers received antiretroviral therapy, while approximately 65% of infants received infant prophylaxis. The Roche SPEX and Abbott technologies had high sensitivity (>95%) and specificity (>98%). The Roche FVE had lower sensitivity (85%) and viral load values. CONCLUSIONS: To simplify and streamline laboratory practices, HIV viral load may be used to diagnose HIV infection in infants, particularly using the Roche SPEX and Abbott technologies.

Cost-effectiveness of Routine Provider-Initiated Testing and Counseling for Children With Undiagnosed HIV in South Africa.

BACKGROUND: We compared the cost-effectiveness of pediatric provider-initiated HIV testing and counseling (PITC) vs no PITC in a range of clinical care settings in South Africa. METHODS: We used the Cost-Effectiveness of Preventing AIDS Complications Pediatric model to simulate a cohort of children, aged 2-10 years, presenting for care in 4 settings (outpatient, malnutrition, inpatient, tuberculosis clinic) with varying prevalence of undiagnosed HIV (1.0%, 15.0%, 17.5%, 50.0%, respectively). We compared "PITC" (routine testing offered to all patients; 97% acceptance and 71% linkage to care after HIV diagnosis) with no PITC. Model outcomes included life expectancy, lifetime costs, and incremental cost-effectiveness ratios (ICERs) from the health care system perspective and the proportion of children with HIV (CWH) diagnosed, on antiretroviral therapy (ART), and virally suppressed. We assumed a threshold of $3200/year of life saved (YLS) to determine cost-effectiveness. Sensitivity analyses varied the age distribution of children seeking care and costs for PITC, HIV care, and ART. RESULTS: PITC improved the proportion of CWH diagnosed (45.2% to 83.2%), on ART (40.8% to 80.4%), and virally suppressed (32.6% to 63.7%) at 1 year in all settings. PITC increased life expectancy by 0.1-0.7 years for children seeking care (including those with and without HIV). In all settings, the ICER of PITC vs no PITC was very similar, ranging from $710 to $1240/YLS. PITC remained cost-effective unless undiagnosed HIV prevalence was <0.2%. CONCLUSIONS: Routine testing improves HIV clinical outcomes and is cost-effective in South Africa if the prevalence of undiagnosed HIV among children exceeds 0.2%. These findings support current recommendations for PITC in outpatient, inpatient, tuberculosis, and malnutrition clinical settings.

Diagnostic Accuracy of Dried Plasma Spot Specimens for HIV-1 Viral Load Testing: A Systematic Review and Meta-analysis.

BACKGROUND: Dried plasma spot specimens may be a viable alternative to traditional liquid plasma in field settings, but the diagnostic accuracy is not well understood. METHODS: Standard databases (PubMed and Medline), conferences, and gray literature were searched until January 2019. The quality of evidence was evaluated using the Standards for Reporting Studies of Diagnostic Accuracy and Quality Assessment of Diagnostic Accuracy Studies-2 criteria. We used univariate and bivariate random effects models to determine misclassification, sensitivity, and specificity across multiple thresholds, overall and for each viral load technology, and to account for between-study variation. RESULTS: We identified 23 studies for inclusion in the systematic review that compared the diagnostic accuracy of dried plasma spots with that of plasma. Primary data from 16 of the 23 studies were shared and included in the meta-analysis, representing 18 countries, totaling 1847 paired dried plasma spot:plasma data points. The mean bias of dried plasma spot specimens compared with that of plasma was 0.28 log10 copies/mL, whereas the difference in median viral load was 2.25 log10 copies/mL. More dried plasma spot values were undetectable compared with plasma values (43.6% vs. 29.8%). Analyzing all technologies together, the sensitivity and specificity of dried plasma spot specimens were >92% across all treatment failure thresholds compared and total misclassification <5.4% across all treatment failure thresholds compared. Some technologies had lower sensitivity or specificity; however, the results were typically consistent across treatment failure thresholds. DISCUSSION: Overall, dried plasma spot specimens performed relatively well compared with plasma with sensitivity and specificity values greater than 90% and misclassification rates less than 10% across all treatment failure thresholds reviewed.

Future directions for HIV service delivery research: Research gaps identified through WHO guideline development.

Nathan Ford and co-authors discuss the systematic identification of research gaps in improving HIV service delivery.

Point-of-care testing can achieve same-day diagnosis for infants and rapid ART initiation: results from government programmes across six African countries.

INTRODUCTION: Point-of-care (POC) early infant diagnosis (EID) testing has been shown to dramatically decrease turnaround times from sample collection to caregiver result receipt and time to ART initiation for HIV-positive infants compared to centralized laboratory testing. As governments in sub-Saharan Africa implement POC EID technologies, we report on the feasibility and effectiveness of POC EID testing and the impact of same-day result delivery on rapid ART initiation within national programmes across six countries. METHODS: This pre-/post-evaluation compared centralized laboratory-based (pre) with POC (post) EID testing in 52 facilities across Cameroon, Democratic Republic of Congo, Ethiopia, Kenya, Senegal and Zimbabwe between April 2017 and October 2019 (country-dependent). Data were collected retrospectively from routine records at health facilities for all infants tested under two years of age. Hazard ratios and 95% confidence intervals were calculated to compare time-to-event outcomes, visualized with Kaplan-Meier curves, and the Somers' D test was used to compare continuous outcomes. RESULTS: Data were collected for 2892 EID tests conducted on centralized laboratory-based platforms and 4610 EID tests on POC devices with 127 (4%) and 192 (4%) HIV-positive infants identified, respectively. POC EID significantly reduced the time from sample collection to caregiver result receipt (POC median: 0 days, IQR: 0 to 0 vs. centralized: 35 days, IQR: 26 to 56) and time from sample collection to ART initiation for HIV-positive infants (POC median: 1 day, IQR: 0 to 7 vs. centralized: 39 days, IQR: 26 to 57). With POC testing, 72% of infants received results on the same day as sample collection; HIV-positive infants with a same-day diagnosis had six times the rate of ART initiation compared to those diagnosed one or more days after sample collection (HR: 6.39; 95% CI: 3.44 to 11.85). CONCLUSIONS: Same-day diagnosis and treatment initiation for infants is possible with POC EID within routine government-led and -supported public sector healthcare facilities in resource-limited settings. Given that POC EID allows for rapid ART initiation, aligning to the World Health Organization's recommendation of ART initiation within seven days, its use in public sector programmes has the potential to reduce overall mortality for infants with HIV through early treatment initiation.

Optimizing infant HIV diagnosis with additional screening at immunization clinics in three sub-Saharan African settings: a cost-effectiveness analysis.

INTRODUCTION: Uptake of early infant HIV diagnosis (EID) varies widely across sub-Saharan African settings. We evaluated the potential clinical impact and cost-effectiveness of universal maternal HIV screening at infant immunization visits, with referral to EID and maternal antiretroviral therapy (ART) initiation. METHODS: Using the CEPAC-Pediatric model, we compared two strategies for infants born in 2017 in Côte d'Ivoire (CI), South Africa (SA), and Zimbabwe: (1) existing EID programmes offering six-week nucleic acid testing (NAT) for infants with known HIV exposure (EID), and (2) EID plus universal maternal HIV screening at six-week infant immunization visits, leading to referral for infant NAT and maternal ART initiation (screen-and-test). Model inputs included published Ivoirian/South African/Zimbabwean data: maternal HIV prevalence (4.8/30.8/16.1%), current uptake of EID (40/95/65%) and six-week immunization attendance (99/74/94%). Referral rates for infant NAT and maternal ART initiation after screen-and-test were 80%. Costs included NAT ($24/infant), maternal screening ($10/mother-infant pair), ART ($5 to 31/month) and HIV care ($15 to 190/month). Model outcomes included mother-to-child transmission of HIV (MTCT) among HIV-exposed infants, and life expectancy (LE) and mean lifetime per-person costs for children with HIV (CWH) and all children born in 2017. We calculated incremental cost-effectiveness ratios (ICERs) using discounted (3%/year) lifetime costs and LE for all children. We considered two cost-effectiveness thresholds in each country: (1) the per-capita GDP ($1720/6380/2150) per year-of-life saved (YLS), and (2) the CEPAC-generated ICER of offering 2 versus 1 lifetime ART regimens (e.g. offering second-line ART; $520/500/580/YLS). RESULTS: With EID, projected six-week MTCT was 9.3% (CI), 4.2% (SA) and 5.2% (Zimbabwe). Screen-and-test decreased total MTCT by 0.2% to 0.5%, improved LE by 2.0 to 3.5 years for CWH and 0.03 to 0.07 years for all children, and increased discounted costs by $17 to 22/child (all children). The ICER of screen-and-test compared to EID was $1340/YLS (CI), $650/YLS (SA) and $670/YLS (Zimbabwe), below the per-capita GDP but above the ICER of 2 versus 1 lifetime ART regimens in all countries. CONCLUSIONS: Universal maternal HIV screening at immunization visits with referral to EID and maternal ART initiation may reduce MTCT, improve paediatric LE, and be of comparable value to current HIV-related interventions in high maternal HIV prevalence settings like SA and Zimbabwe.

Evaluation of near point-of-care viral load implementation in public health facilities across seven countries in sub-Saharan Africa.

INTRODUCTION: In many low- and middle-income countries, HIV viral load (VL) testing occurs at centralized laboratories and time-to-result-delivery is lengthy, preventing timely monitoring of HIV treatment adherence. Near point-of-care (POC) devices, which are placed within health facility laboratories rather than clinics themselves (i.e. "true" POC), can offer VL in conjunction with centralized laboratories to expedite clinical decision making and improve outcomes, especially for patients at high risk of treatment failure. We assessed impacts of near-POC VL testing on result receipt and clinical action in public sector programmes in Cameroon, Democratic Republic of Congo, Kenya, Malawi, Senegal, Tanzania and Zimbabwe. METHODS: Routine health data were collected retrospectively after introducing near-POC VL testing at 57 public sector health facilities (2017 to 2019, country-dependent). Where possible, key indicators were compared to data from patients receiving centralized laboratory testing using hazard ratios and the Somers' D test. RESULTS: Data were collected from 6795 tests conducted on near-POC and 17614 tests on centralized laboratory-based platforms. Thirty-one percent (2062/6694) of near-POC tests were conducted for high-risk populations: pregnant and breastfeeding women, children and those with suspected failure. Compared to conventional testing, near-POC improved the median time from sample collection to return of results to patient [six vs. sixty-eight days, effect size: -32.2%; 95% CI: -41.0% to -23.4%] and to clinical action for individuals with an elevated HIV VL [three vs. fourty-nine days, effect size: -35.4%; 95% CI: -46.0% to -24.8%]. Near-POC VL results were two times more likely to be returned to the patient within 90 days compared to centralized tests [50% (1781/3594) vs. 27% (4172/15271); aHR: 2.22, 95% CI: 2.05 to 2.39]. Thirty-seven percent (340/925) of patients with an elevated near-POC HIV VL result had documented clinical follow-up actions within 30 days compared to 7% (167/2276) for centralized testing. CONCLUSIONS: Near-POC VL testing enabled rapid test result delivery for high-risk populations and led to significant improvements in the timeliness of patient result receipt compared to centralized testing. While there was some improvement in time-to-clinical action with near-POC VL testing, major gaps remained. Strengthening of systems supporting the utilization of results for patient management are needed to truly capitalize on the benefits of decentralized testing.

Modeling the cost-effectiveness of point-of-care platforms for infant diagnosis of HIV in sub-Saharan African countries.

BACKGROUND: Early infant diagnosis of HIV (EID) improves child survival through earlier initiation of antiretroviral therapy (ART). In many settings, ART initiation is hindered by delays in testing performed in centralized labs. Point-of-care (PoC) platforms offer opportunities to improve the timeliness of ART initiation. METHODS: We used a mathematical model to estimate the costs and performance of on-site PoC testing using three platforms (m-PIMA, GeneXpert IV, and GeneXpert Edge) compared with the standard of care (SoC). Primary outcomes included ART initiation within 60 days of sample collection, HIV-related mortality before ART initiation, and incremental cost-effectiveness ratios (ICERs). RESULTS: PoC testing significantly increased ART initiation within 60 days (from 19% with SoC to 82-84% with PoC) and decreased HIV-related mortality (from 23% with SoC to 5% with PoC). ART initiation and mortality were similar across PoC platforms. When only used for EID and with high coverage of prevention of mother-to-child transmission (PMTCT) programs, ICERs for PoC testing compared with the SoC ranged from $430 to $1097 per additional infant on ART within 60 days and from $1527 to $3888 per death averted. PoC-based testing was more cost-effective in settings with lower PMTCT coverage, greater delays in the SoC, and when PoC instruments could be integrated with other disease programs. CONCLUSION: Our findings illustrate that PoC platforms can dramatically improve the timeliness of EID and linkage to HIV care. The cost-effectiveness of PoC platforms depends on the cost of PoC testing, existing access to diagnostic testing, and the ability to integrate PoC testing with non-EID programs.

Mixed-method estimation of population-level HIV viral suppression rate in the Western Cape, South Africa.

INTRODUCTION: There are few population-wide data on viral suppression (VS) that can be used to monitor programmatic targets in sub-Saharan Africa. We describe how routinely collected viral load (VL) data from antiretroviral therapy (ART) programmes can be extrapolated to estimate population VS and validate this using a combination of empiric and model-based estimates. METHODS: VL test results from were matched using a record linkage algorithm to obtain linked results for individuals. Test-level and individual-level VS rates were based on test VL values <1000 cps/mL, and individual VL <1000 cps/mL in a calendar year, respectively. We calculated population VS among people living with HIV (PLWH) in the province by combining census-derived midyear population estimates, HIV prevalence estimates and individual level VS estimates from routine VL data. RESULTS: Approximately 1.9 million VL test results between 2008 and 2018 were analysed. Among individuals in care, VS increased from 85.5% in 2008 to 90% in 2018. Population VS among all PLWH in the province increased from 12.2% in 2008 to 51.0% in 2017. The estimates derived from this method are comparable to those from other published studies. Sensitivity analyses showed that the results are robust to variations in linkage method, but sensitive to the extreme combinations of assumed VL testing coverage and population HIV prevalence. CONCLUSION: While validation of this method in other settings is required, this approach provides a simple, robust method for estimating population VS using routine data from ART services that can be employed by national programmes in high-burden settings.

Building and Sustaining Optimized Diagnostic Networks to Scale-up HIV Viral Load and Early Infant Diagnosis.

BACKGROUND: Progress toward meeting the UNAIDS 2014 HIV treatment (90-90-90) targets has been slow in some countries because of gaps in access to HIV diagnostic tests. Emerging point-of-care (POC) molecular diagnostic technologies for HIV viral load (VL) and early infant diagnosis (EID) may help reduce diagnostic gaps. However, these technologies need to be implemented in a complementary and strategic manner with laboratory-based instruments to ensure optimization. METHOD: Between May 2019 and February 2020, a systemic literature search was conducted in PubMed, the Cochrane Library, MEDLINE, conference abstracts, and other sources such as Unitaid, UNAIDS, WHO, and UNICEF websites to determine factors that would affect VL and EID scale-up. Data relevant to the search themes were reviewed for accuracy and were included. RESULTS: Collaborations among countries, implementing partners, and donors have identified a set of framework for the effective use of both POC-based and laboratory-based technologies in large-scale VL and EID testing programs. These frameworks include (1) updated testing policies on the operational utility of POC and laboratory-based technologies, (2) expanded integrated testing using multidisease diagnostic platforms, (3) laboratory network mapping, (4) use of more efficient procurement and supply chain approaches such as all-inclusive pricing and reagent rental, and (5) addressing systemic issues such as test turnaround time, sample referral, data management, and quality systems. CONCLUSIONS: Achieving and sustaining optimal VL and EID scale-up within tiered diagnostic networks would require better coordination among the ministries of health of countries, donors, implementing partners, diagnostic manufacturers, and strong national laboratory and clinical technical working groups.

Viral load assay performs comparably to early infant diagnosis assay to diagnose infants with HIV in Mozambique: a prospective observational study

Introduction: Viral load testing is essential to manage HIV disease, especially in infants and children. Early infant diagnosis (EID) is performed using nucleic-acid testing in children under 18 months. Resource-limited health systems face severe challenges to scale-up both viral load and EID to unprecedented levels. Streamlining laboratory systems would be beneficial to improve access to quality testing and to increase efficiency of antiretroviral treatment programmes. We evaluated the performance of viral load testing to serve as an EID assay in children younger than 18 months. Methods: This study was an observational, prospective study, including children between one and 18 months of age who were born to HIV-positive mothers in 134 health facilities in Maputo City and Maputo Province, Mozambique. Dried blood spot specimens from heel or toe pricks were collected between January and April 2018, processed using SPEX buffer for both assays, and tested for routine EID and viral load testing using the Roche CAP/CTM HIV-1 Qualitative v2 and Roche CAP/ CTM HIV-1 Quantitative v2 assays respectively. The sensitivity, specificity and positive and negative predictive values were estimated using the EID results as the reference standard. Results: A total of 1021 infants were included in the study, of which 47% were female. Over 95% of mothers and children were on antiretroviral treatment or received antiretroviral prophylaxis respectively. The sensitivity and specificity of using the viral load assay to detect infection were 100% (95% CI: 96.2 to 100%) and 99.9% (95% CI: 99.4 to 100%). The positive and negative predictive values were 99.0% (95% CI: 94.3 to 100%) and 100% (95% CI: 99.6 to 100%). The McNemar's test was 1.000 and Cohen's kappa was 0.994. Conclusions: The comparable performance suggests that viral load assays can be used as an infant diagnostic assay. Infants with either low levels of viraemia or high cycle threshold values should be repeat tested to ensure the result is truly positive prior to treatment initiation, regardless of assay used. Viral load assays could replace traditional EID testing, substantially streamlining molecular laboratory services for children and lowering costs, with the additional advantage of providing baseline viral load results for antiretroviral treatment management.