Estimates of the prevalence of undiagnosed HIV among children living with HIV in Eswatini, Lesotho, Malawi, Namibia, Tanzania, Zambia, and Zimbabwe from 2015 to 2017: an analysis of data from the cross-sectional Population-based HIV Impact Assessment surveys.

BACKGROUND: In 2020, there were an estimated 1·7 million children younger than 15 years living with HIV worldwide, but there are few data on the proportion of children living with HIV who are undiagnosed. We aimed to estimate the prevalence of undiagnosed HIV among children living with HIV in Eswatini, Lesotho, Malawi, Namibia, Tanzania, Zambia, and Zimbabwe. METHODS: We conducted an analysis of data from the cross-sectional Population-based HIV Impact Assessment (PHIA) surveys from 2015 to 2017. PHIAs are nationally representative surveys measuring HIV outcomes. HIV rapid test data (with PCR confirmatory testing for children aged <18 months) were used to measure HIV prevalence among children in each country (Eswatini, Lesotho, Malawi, Namibia, Tanzania, Zambia, and Zimbabwe). Mothers or guardians reported previous HIV testing of children and previous results. Detection of antiretroviral medications was done using dried blood spots. Children who tested positive in the PHIA with previous negative or unknown HIV test results and without detectable antiretroviral medication blood concentrations were considered previously undiagnosed; all other children who tested positive were considered previously diagnosed. Survey weights with jackknife variance were used to generate national estimates of HIV prevalence and undiagnosed HIV in children aged 1-14 years. We also report the prevalence (weighted proportions) of antiretroviral therapy coverage and viral load suppression (<400 copies per mL). FINDINGS: Between 2015 and 2017, 42 248 children aged 1-14 years were included in the surveys, of whom 594 were living with HIV. Across the seven countries, the estimated weighted HIV prevalence was 0·9% (probability band 0·7-1·1) and we estimated that there were 425 000 (probability band 365 000-485 000) children living with HIV. Among all children living with HIV, 61·0% (n=259 000 [probability band 216 000-303 000]) were previously diagnosed and 39·0% (n=166 000 [128 000-204 000]) had not been previously diagnosed with HIV. Among previously diagnosed children living with HIV, 88·4% had detectable antiretroviral medication blood concentrations and 48·3% had viral load suppression. Among all children living with HIV (regardless of previous diagnosis status), 54·7% had detectable antiretroviral medication blood concentrations and 32·6% had viral load suppression. INTERPRETATION: Our findings show the uneven coverage of paediatric HIV testing across these seven countries and underscore the urgent need to address gaps in diagnosis and treatment for all children living with HIV. FUNDING: None.

Progress towards 2020 global HIV impact and treatment targets.

INTRODUCTION: Over the past 20 years, the response to the HIV epidemic has achieved remarkable results. These results have often been motivated by targets adopted by countries through United Nations (UN) Political Declarations on HIV. The 2016 political declaration included two impact targets, to achieve a 75% decline in new HIV infections and AIDS-related deaths between 2010 and 2020, and to reach the 90-90-90 testing and treatment targets by 2020. Our objective is to summarize progress towards these targets using robust and comparable HIV estimates released by UNAIDS in July 2021. In addition, we comment on the importance of targets and the modelled estimates required to quantify those targets. DISCUSSION: The UNAIDS estimates indicate that at the global and regional levels, the 2020 targets were missed: new infections declined by 31% and AIDS-related deaths declined by 47% between 2010 and 2020, compared to a target of 75% decline for both indicators. Similarly, no region achieved the 90-90-90 testing and treatment targets. Some countries, in diverse settings, achieved these targets showing that the targets were not overly ambitious if the right funding, policies and evidence-informed interventions at the right scale were in place. The 2021 UN Political Declaration on HIV, adopted on 8 June 2021, has set out a new set of ambitious but achievable targets for 2025. The 2025 targets and the required actions to reach those targets are described in the Global AIDS Strategy 2021-2026, which provides a framework to reprioritize HIV responses by reducing inequalities and building on the achievements of multiple Sustainable Development Goals. The Strategy encourages countries to monitor progress against targets for different geographic areas and populations to maximize equitable services and ensure accountability and also to understand why targets are being missed. CONCLUSIONS: The UNAIDS epidemiological estimates provide information that promote accountability and estimate progress towards global targets at the national level. Additional strategic information and analyses are required to identify the populations that are furthest from the targets and the programmes and policies that are keeping countries from meeting their targets.

Monitoring the status of selected health related sustainable development goals: methods and projections to 2030.

Background: Monitoring Sustainable Development Goal indicators (SDGs) and their targets plays an important role in understanding and advocating for improved health outcomes for all countries. We present the United Nations (UN) Inter-agency groups' efforts to support countries to report on SDG health indicators, project progress towards 2030 targets and build country accountability for action. Objective: We highlight common principles and practices of each Inter-agency group and the progress made towards SDG 3 targets using seven health indicators as examples. The indicators used provide examples of best practice for modelling estimates and projections using standard methods, transparent data collection and country consultations. Methods: Practices common to the UN agencies include multi-UN agency participation, expert groups to advise on estimation methods, transparent publication of methods and data inputs, use of UN-derived population estimates, country consultations, and a common reporting platform to present results. Our seven examples illustrate how estimates, using mostly Bayesian models, make use of country data to track progress towards SDG targets for 2030. Results: Progress has been made over the past decade. However, none of the seven indicators are on track to achieve their respective SDG targets by 2030. Accelerated efforts are needed, especially in low- and middle-income countries, to reduce the burden of maternal, child, communicable and noncommunicable disease mortality, and to provide access to modern methods of family planning to all women. Conclusion: Our analysis shows the benefit of UN interagency monitoring which prioritizes transparent country data sources, UN population estimates and life tables, and rigorous but replicable modelling methods. Countries are supported to build capacity for data collection, analysis and reporting. Through these monitoring efforts we support countries to tackle even the most intransient health issues, including the pandemic caused by SARS-CoV-2 that is reversing the hard-earned gains of all countries.

Summarizing the results and methods of the 2019 Joint United Nations Programme on HIV/AIDS HIV estimates.

: UNAIDS and other partners provide support to countries to develop estimates of HIV and related indicators on an annual basis. These estimates are used to monitor epidemic trends, guide program planning and resource allocation, and inform policy decision-making. The collection of articles in this AIDS supplement provide the headline results for the 2019 UNAIDS estimates and describe the new developments in the methods used to produce these estimates.

Global and regional trends of people living with HIV aged 50 and over: Estimates and projections for 2000-2020.

BACKGROUND: The increasing numbers of people living with HIV (PLHIV) who are receiving antiretroviral therapy (ART) have near normal life-expectancy, resulting in more people living with HIV over the age of 50 years (PLHIV50+). Estimates of the number of PLHIV50+ are needed for the development of tailored therapeutic and prevention interventions at country, regional and global level. METHODS: The AIDS Impact Module of the Spectrum software was used to compute the numbers of PLHIV, new infections, and AIDS-related deaths for PLHIV50+ for the years 2000-2016. Projections until 2020 were calculated based on an assumed ART scale-up to 81% coverage by 2020, consistent with the UNAIDS 90-90-90 treatment targets. RESULTS: Globally, there were 5.7 million [4.7 million- 6.6 million] PLHIV50+ in 2016. The proportion of PLHIV50+ increased substantially from 8% in 2000 to 16% in 2016 and is expected to increase to 21% by 2020. In 2016, 80% of PLHIV50+ lived in low- and middle-income countries (LMICs), with Eastern and Southern Africa containing the largest number of PLHIV50+. While the proportion of PLHIV50+ was greater in high income countries, LMICs have higher numbers of PLHIV50+ that are expected to continue to increase by 2020. CONCLUSIONS: The number of PLHIV50+ has increased dramatically since 2000 and this is expected to continue by 2020, especially in LMICs. HIV prevention campaigns, testing and treatment programs should also focus on the specific needs of PLHIV50+. Integrated health and social services should be developed to cater for the changing physical, psychological and social needs of PLHIV50+, many of whom will need to use HIV and non-HIV services.

Simulation Modeling and Metamodeling to Inform National and International HIV Policies for Children and Adolescents.

OBJECTIVE AND APPROACH: Computer-based simulation models serve an important purpose in informing HIV care for children and adolescents. We review current model-based approaches to informing pediatric and adolescent HIV estimates and guidelines. FINDINGS: Clinical disease simulation models and epidemiologic models are used to inform global and regional estimates of numbers of children and adolescents living with HIV and in need of antiretroviral therapy, to develop normative guidelines addressing strategies for diagnosis and treatment of HIV in children, and to forecast future need for pediatric and adolescent antiretroviral therapy formulations and commodities. To improve current model-generated estimates and policy recommendations, better country-level and regional-level data are needed about children living with HIV, as are improved data about survival and treatment outcomes for children with perinatal HIV infection as they age into adolescence and adulthood. In addition, novel metamodeling and value of information methods are being developed to improve the transparency of model methods and results, as well as to allow users to more easily tailor model-based analyses to their own settings. CONCLUSIONS: Substantial progress has been made in using models to estimate the size of the pediatric and adolescent HIV epidemic, to inform the development of guidelines for children and adolescents affected by HIV, and to support targeted implementation of policy recommendations to maximize impact. Ongoing work will address key limitations and further improve these model-based projections.

Developing and implementing national health identifiers in resource limited countries: why, what, who, when and how?

Many resource-limited countries are scaling up health services and health-information systems (HISs). The HIV Cascade framework aims to link treatment services and programs to improve outcomes and impact. It has been adapted to HIV prevention services, other infectious and non-communicable diseases, and programs for specific populations. Where successful, it links the use of health services by individuals across different disease categories, time and space. This allows for the development of longitudinal health records for individuals and de-identified individual level information is used to monitor and evaluate the use, cost, outcome and impact of health services. Contemporary digital technology enables countries to develop and implement integrated HIS to support person centred services, a major aim of the Sustainable Development Goals. The key to link the diverse sources of information together is a national health identifier (NHID). In a country with robust civil protections, this should be given at birth, be unique to the individual, linked to vital registration services and recorded every time that an individual uses health services anywhere in the country: it is more than just a number as it is part of a wider system. Many countries would benefit from practical guidance on developing and implementing NHIDs. Organizations such as ASTM and ISO, describe the technical requirements for the NHID system, but few countries have received little practical guidance. A WHO/UNAIDS stake-holders workshop was held in Geneva, Switzerland in July 2016, to provide a 'road map' for countries and included policy-makers, information and healthcare professionals, and members of civil society. As part of any NHID system, countries need to strengthen and secure the protection of personal health information. While often the technology is available, the solution is not just technical. It requires political will and collaboration among all stakeholders to be successful.

The Network Survival Method for Estimating Adult Mortality: Evidence From a Survey Experiment in Rwanda.

Adult death rates are a critical indicator of population health and well-being. Wealthy countries have high-quality vital registration systems, but poor countries lack this infrastructure and must rely on estimates that are often problematic. In this article, we introduce the network survival method, a new approach for estimating adult death rates. We derive the precise conditions under which it produces consistent and unbiased estimates. Further, we develop an analytical framework for sensitivity analysis. To assess the performance of the network survival method in a realistic setting, we conducted a nationally representative survey experiment in Rwanda (n = 4,669). Network survival estimates were similar to estimates from other methods, even though the network survival estimates were made with substantially smaller samples and are based entirely on data from Rwanda, with no need for model life tables or pooling of data from other countries. Our analytic results demonstrate that the network survival method has attractive properties, and our empirical results show that this method can be used in countries where reliable estimates of adult death rates are sorely needed.

Producing HIV estimates: from global advocacy to country planning and impact measurement.

BACKGROUND: The development of global HIV estimates has been critical for understanding, advocating for and funding the HIV response. The process of generating HIV estimates has been cited as the gold standard for public health estimates. OBJECTIVE: This paper provides important lessons from an international scientific collaboration and provides a useful model for those producing public health estimates in other fields. DESIGN: Through the compilation and review of published journal articles, United Nations reports, other documents and personal experience we compiled historical information about the estimates and identified potential lessons for other public health estimation efforts. RESULTS: Through the development of core partnerships with country teams, implementers, demographers, mathematicians, epidemiologists and international organizations, UNAIDS has led a process to develop the capacity of country teams to produce internationally comparable HIV estimates. The guidance provided by these experts has led to refinements in the estimated numbers of people living with HIV, new HIV infections and AIDS-related deaths over the past 20 years. A number of important updates to the methods since 1997 resulted in fluctuations in the estimated levels, trends and impact of HIV. The largest correction occurred between the 2005 and 2007 rounds with the additions of household survey data into the models. In 2001 the UNAIDS models at that time estimated there were 40 million people living with HIV. In 2016, improved models estimate there were 30 million (27.6-32.7 million) people living with HIV in 2001. CONCLUSIONS: Country ownership of the estimation tools has allowed for additional uses of the results than had the results been produced by researchers or a team in Geneva. Guidance from a reference group and input from country teams have led to critical improvements in the models over time. Those changes have improved countries' and stakeholders' understanding of the HIV epidemic.

The impact and cost of the 2013 WHO recommendations on eligibility for antiretroviral therapy.

OBJECTIVES: The present study presents estimates of the number of people who would become newly eligible for antiretroviral therapy if all countries adopted the 2013 WHO treatment guidelines. It also shows the cost and impact that would result if coverage expanded to 80% of those eligible. METHODS: The AIDS Impact Model (AIM) and the Goals model within the Spectrum modelling system were used for these estimates. Projections of costs and AIDS deaths are based on estimates for 116 low-income and middle-income countries. Projections of impact on HIV incidence are based on simulation modelling for 24 high burden countries, with the results scaled up to represent all low-income and middle-income countries. RESULTS: If the 2013 guidelines were adopted universally, the number eligible for treatment would rise to 28.6 million in 2013. Achieving 80% coverage would mean 28 million on antiretroviral therapy by 2025, and would avert 2.9 million deaths and 3.9 million new infections from 2013 to 2025 compared with the 2010 guidelines. CONCLUSION: The 2013 guidelines significantly expand the number eligible for treatment. Reaching those newly eligible will require additional resources, but is likely to produce significant benefits.

The costs and benefits of Option B+ for the prevention of mother-to-child transmission of HIV.

OBJECTIVE: Most countries follow WHO 2010 guidelines for the prevention of mother-to-child transmission (PMTCT) of HIV using either Option A or B for women not yet eligible for antiretroviral therapy (ART). Both of these approaches involve the use of antiretrovirals during pregnancy and breastfeeding. Some countries have adopted a new strategy, Option B+, in which HIV-positive pregnant women are started immediately on ART and continued for life. Option B+ is more costly than Options A or B, but provides additional health benefits. In this article, we estimate the additional costs and effectiveness of Option B+. METHODS: We developed a deterministic model to simulate births, breastfeeding, and HIV infection in women in four countries, Kenya, Zambia, South Africa, and Vietnam that differ in fertility rate, birth interval, age at first birth, and breastfeeding patterns, but have similar age at HIV infection. We estimated the total PMTCT costs and new child infections under Options A, B, and B+, and measured cost-effectiveness as the incremental PMTCT-related costs per child infection averted. We included adult sexual transmissions averted from ART, the corresponding costs saved, and estimated the total incremental cost per transmission (child and adult) averted. RESULTS: When considering PMTCT-related costs and child infections, Option B+ was the most cost-effective strategy costing between $6000 and $23 000 per infection averted compared with Option A. Option B+ averted more child infections compared with Option B in all four countries and cost less than Option B in Kenya and Zambia. When including adult sexual transmissions averted, Option B+ cost less and averted more infections than Options A and B.

What will it take to achieve virtual elimination of mother-to-child transmission of HIV? An assessment of current progress and future needs.

BACKGROUND: The number of HIV-positive pregnant women receiving antiretroviral drugs (ARVs) to prevent mother-to-child transmission (MTCT) of HIV has increased rapidly. OBJECTIVE: To estimate the reduction in new child HIV infections resulting from prevention of MTCT (PMTCT) over the past decade. To project the potential impact of implementing the new WHO PMTCT guidelines between 2010 and 2015 and consider the efforts required to virtually eliminate MTCT, defined as <5% transmission of HIV from mother to child, or 90% reduction of infections among young children by 2015. METHODS: Data from 25 countries with the largest numbers of HIV-positive pregnant women were used to create five scenarios to evaluate different PMTCT interventions. A demographic model, Spectrum, was used to estimate new child HIV infections as a measure of the impact of interventions. RESULTS: Between 2000 and 2009 there was a 24% reduction in the estimated annual number of new child infections in the 25 countries, of which about one-third occurred in 2009 alone. If these countries implement the new WHO PMTCT recommendations between 2010 and 2015, and provide more effective ARV prophylaxis or treatment to 90% of HIV-positive pregnant women, 1 million new child infections could be averted by 2015. Reducing HIV incidence in reproductive age women, eliminating the current unmet need for family planning and limiting the duration of breastfeeding to 12 months (with ARV prophylaxis) could avert an additional 264 000 infections, resulting in a total reduction of 79% of annual new child infections between 2009 and 2015, approaching but still missing the goal of virtual elimination of MTCT. DISCUSSION: To achieve virtual elimination of new child infections PMTCT programmes must achieve high coverage of more effective ARV interventions and safer infant feeding practices. In addition, a comprehensive approach including meeting unmet family planning needs and reducing new HIV infections among reproductive age women will be required.

The impact of orphanhood on food security in the high-HIV context of Blantyre, Malawi.

BACKGROUND: A 2004 UNICEF/UNAIDS/USAID survey in Blantyre, Malawi, examined methods to improve monitoring and evaluation of interventions aimed at orphans and vulnerable children. OBJECTIVE: A derivative of this larger study, the present study utilized the household data collected to assess differences in food security status among orphan households with the aim of helping food security programmers focus resources on the households most affected. METHODS: Orphan households were classified by number and type of orphans supported. Descriptive analyses and logistic regressions were performed to assess differential vulnerability to food insecurity according to these classifications. RESULTS: Multiple-orphan households and multiple-orphan households that cared for at least one foster child were 2.42 and 6.87 times more likely to be food insecure, respectively, than nonorphan households. No other category of orphan household was at elevated risk. CONCLUSIONS: The food security impact of caring for orphans varied significantly among orphan households, requiring food security planners to focus resources on the households most heavily impacted by HIV/AIDS, including multiple-orphan households, rather than focusing on conventional designations of vulnerability, such as orphans and vulnerable children.

Estimation of antiretroviral therapy coverage: methodology and trends.

PURPOSE OF REVIEW: To present the methodology used to calculate coverage of antiretroviral therapy (ART) and review global and regional trends in ART coverage. RECENT FINDINGS: There has been a steady increase in ART coverage over the last decade with a more rapid increase in recent years. Current estimates of ART coverage are 43% for adults and 38% for children (ages 0-14 years). Methods for calculating coverage rely on good-quality patient monitoring systems in countries, and well informed models are needed to estimate the number of people in need of treatment. SUMMARY: The estimated coverage rates show that ART programs have improved over the past 8 years; however, approximately 58% (53-60%) of those people in need of ART are still not on treatment. High quality data are needed to accurately measure changes in ART coverage.