Updates to the Spectrum/AIM model for the UNAIDS 2020 HIV estimates

New sexually transmitted HIV infections from 2016 to 2050 in Guangdong Province, China: a study based on a dynamic compartmental model

BACKGROUND

In Guangdong Province, China, there is lack of information on the HIV epidemic among high-risk groups and the general population, particularly in relation to sexual transmission, which is a predominant route. The new HIV infections each year is also uncertain owing to HIV transmission from men who have sex with men (MSM) to women, as a substantial proportion of MSM also have female sexual partnerships to comply with social demands in China.

METHODS

A deterministic compartmental model was developed to predict new HIV infections in four risk groups, including heterosexual men and women and low- and high-risk MSM, in Guangdong Province from 2016 to 2050, considering HIV transmission from MSM to women. The new HIV infections and its 95% credible interval (CrI) were predicted. An adaptive sequential Monte Carlo method for approximate Bayesian computation (ABC-SMC) was used to estimate the unknown parameter, a mixing index. We calibrated our results based on new HIV diagnoses and proportions of late diagnoses. The Morris and Sobol methods were applied in the sensitivity analysis.

RESULTS

New HIV infections increased during and 2 years after the COVID-19 pandemic, then declined until 2050. New infections rose from 8,828 [95% credible interval (CrI): 6,435-10,451] in 2016 to 9,652 (95% CrI: 7,027-11,434) in 2019, peaking at 11,152 (95% CrI: 8,337-13,062) in 2024 before declining to 7,084 (95% CrI: 5,165-8,385) in 2035 and 4,849 (95% CrI: 3,524-5,747) in 2050. Women accounted for approximately 25.0% of new HIV infections, MSM accounted for 40.0% (approximately 55.0% of men), and high-risk MSM accounted for approximately 25.0% of the total. The ABC-SMC mixing index was 0.504 (95% CrI: 0.239-0.894).

CONCLUSIONS

Given that new HIV infections and the proportion of women were relatively high in our calibrated model, to some extent, the HIV epidemic in Guangdong Province remains serious, and services for HIV prevention and control are urgently needed to return to the levels before the COVID-19 epidemic, especially in promoting condom-based safe sex and increasing awareness of HIV prevention to general population.

HIV and hepatitis B, C co-infection and correlates of HIV infection among men who have sex with men in Rwanda, 2021: a respondent-driven sampling, cross-sectional study

BACKGROUND

Men who have sex with men (MSM) are a key population group disproportionately affected by HIV and other sexually transmitted infections (STIs) worldwide. In Rwanda, the HIV epidemic remains a significant public health concern, and understanding the burden of HIV and hepatitis B and C coinfections among MSM is crucial for designing effective prevention and control strategies. This study aims to determine the prevalence of HIV, hepatitis B, and hepatitis C infections among MSM in Rwanda and identify correlates associated with HIV infection within this population.

METHODS

We used respondent-driven sampling (RDS) to recruit participants between November and December 2021. A face-to-face, structured questionnaire was administered. Testing for HIV infection followed the national algorithm using two rapid tests: Alere Combo and STAT PAK as the first and second screening tests, respectively. Hepatitis B surface antigen (HBsAg) and anti-HCV tests were performed. All statistics were adjusted for RDS design, and a multivariable logistic regression model was constructed to identify factors associated with HIV infection.

RESULTS

The prevalence of HIV among MSM was 6·9% (95% CI: 5·5-8·6), and among HIV-positive MSM, 12·9% (95% CI: 5·5-27·3) were recently infected. The prevalence of hepatitis B and C was 4·2% (95% CI: 3·0-5·7) and 0·7% (95% CI: 0·4-1·2), respectively. HIV and hepatitis B virus coinfection was 0·5% (95% CI: 0·2-1·1), whereas HIV and hepatitis C coinfection was 0·1% (95% CI: 0·0-0·5), and no coinfection for all three viruses was observed. MSM groups with an increased risk of HIV infection included those who ever suffered violence or abuse because of having sex with other men (AOR: 3·42; 95% CI: 1·87-6·25), those who refused to answer the question asking about 'ever been paid money, goods, or services for sex' (AOR: 10·4; 95% CI: 3·30-32·84), and those not consistently using condoms (AOR: 3·15; 95% CI: 1·31-7·60).

CONCLUSION

The findings suggest more targeted prevention and treatment approaches and underscore the importance of addressing structural and behavioral factors contributing to HIV vulnerability, setting interventions to reduce violence and abuse against MSM, promoting safe and consensual sexual practices, and expanding access to HIV prevention tools such as condoms and preexposure prophylaxis (PrEP).

Central auditory test performance predicts future neurocognitive function in children living with and without HIV

Tests of the brain's ability to process complex sounds (central auditory tests) correlate with overall measures of neurocognitive performance. In the low- middle-income countries where resources to conduct detailed cognitive testing is limited, tests that assess the central auditory system may provide a novel and useful way to track neurocognitive performance. This could be particularly useful for children living with HIV (CLWH). To evaluate this, we administered central auditory tests to CLWH and children living without HIV and examined whether central auditory tests given early in a child's life could predict later neurocognitive performance. We used a machine learning technique to incorporate factors known to affect performance on neurocognitive tests, such as education. The results show that central auditory tests are useful predictors of neurocognitive performance and perform as well or in some cases better than factors such as education. Central auditory tests may offer an objective way to track neurocognitive performance in CLWH.

The Tuberculosis Sentinel Research Network (TB-SRN) of the International epidemiology Databases to Evaluate AIDS (IeDEA): protocol for a prospective cohort study in Africa, Southeast Asia and Latin America

INTRODUCTION

Tuberculosis (TB) is a leading infectious cause of death globally. It is the most common opportunistic infection in people living with HIV, and the most common cause of their morbidity and mortality. Following TB treatment, surviving individuals may be at risk for post-TB lung disease. The TB Sentinel Research Network (TB-SRN) provides a platform for coordinated observational TB research within the International epidemiology Databases to Evaluate AIDS (IeDEA) consortium.

METHODS AND ANALYSIS

This prospective, observational cohort study will assess treatment and post-treatment outcomes of pulmonary TB (microbiologically confirmed or clinically diagnosed) among 2600 people aged ≥15 years, with and without HIV coinfection, consecutively enrolled at 16 sites in 11 countries, across 6 of IeDEA's global regions. Data regarding clinical and sociodemographic factors, mental health, health-related quality of life, pulmonary function, and laboratory and radiographic findings will be collected using standardised questionnaires and data collection tools, beginning from the initiation of TB treatment and through 12 months after the end of treatment. Data will be aggregated for proposed analyses.

ETHICS AND DISSEMINATION

Ethics approval was obtained at all implementing study sites, including the Vanderbilt University Medical Center Human Research Protections Programme. Participants will provide informed consent; for minors, this includes both adolescent assent and the consent of their parent or primary caregiver. Protections for vulnerable groups are included, in alignment with local standards and considerations at sites. Procedures for requesting use and analysis of TB-SRN data are publicly available. Findings from TB-SRN analyses will be shared with national TB programmes to inform TB programming and policy, and disseminated at regional and global conferences and other venues.

Methods and Assumptions for Estimating Key HIV Indicators in the UNAIDS Annual Estimates Process

BACKGROUND

Each year UNAIDS supports national teams to estimate key HIV indicators using their latest data. These estimates are produced using a collection of models and software tools. This paper describes the demographic and HIV projection models used in this process.

METHODS

The demographic model (DemProj) projects the population by sex and single age for each year of the estimate. This information is fed into the HIV model (AIDS Impact Model) to estimate key HIV indicators. The model uses program, survey and surveillance data along with incidence trends produced through 1 of several separate models, to estimate new HIV infections, HIV-related deaths, and the population living with HIV by sex, age, CD4 category, and treatment status.

RESULTS

These models allow the annual production of estimates of key HIV indicators including uncertainty intervals. This information is used to track progress toward national and global goals and to develop national strategic plans, Global Fund applications and PEPFAR country operational plans.

CONCLUSIONS

Under the guidance of the UNAIDS Reference Group on Estimates, Modeling and Projections, these models are updated on a regular basis in response to evolving programmatic needs, new data, and analyses. This process of continuous review and improvement has led to mature models that make the best use of available data to provide estimates of indicators important to monitoring progress and developing future plans.

The AIDS Epidemic Model 2023 for Estimating HIV Trends and Transmission Dynamics in Asian Epidemic Settings

BACKGROUND

Thirteen Asian countries use the AIDS Epidemic Model (AEM) as their HIV model of choice. This article describes AEM, its inputs, and its application to national modeling.

SETTING

AEM is an incidence tool used by Spectrum for the Joint United Nations Programme on HIV/AIDS global estimates process.

METHODS

AEM simulates transmission of HIV among key populations (KPs) using measured trends in risk behaviors. The inputs, structure and calculations, interface, and outputs of AEM are described. The AEM process includes (1) collating and synthesizing data on KP risk behaviors, epidemiology, and size to produce model input trends; (2) calibrating the model to observed HIV prevalence; (3) extracting outputs by KP to describe epidemic dynamics and assist in improving responses; and (4) importing AEM incidence into Spectrum for global estimates. Recent changes to better align AEM mortality with Spectrum and add preexposure prophylaxis are described.

RESULTS

The application of AEM in Thailand is presented, describing the outputs and uses in-country. AEM replicated observed epidemiological trends when given observed behavioral inputs. The strengths and limitations of AEM are presented and used to inform thoughts on future directions for global models.

CONCLUSIONS

AEM captures regional HIV epidemiology well and continues to evolve to meet country and global process needs. The addition of time-varying mortality and progression parameters has improved the alignment of the key population compartmental model of AEM with the age-sex-structured national model of Spectrum. Many of the features of AEM, including tracking the sources of infections over time, should be incorporated in future global efforts to build more generalizable models to guide policy and programs.

Differences in Breastfeeding Duration by Maternal HIV Status: A Pooled Analysis of Nationally Representative Surveys in Sub-Saharan Africa

BACKGROUND

Breastfeeding improves child survival but is a source of mother-to-child HIV transmission among women with unsuppressed HIV infection. Estimated HIV incidence in children is sensitive to breastfeeding duration among mothers living with HIV (MLHIV). Breastfeeding duration may vary according to maternal HIV status.

SETTING

Sub-Saharan Africa.

METHODS

We analyzed pooled data from nationally representative household surveys conducted during 2003-2019 that included HIV testing and elicited breastfeeding practices. We fitted survival models of breastfeeding duration by country, year, and maternal HIV status for 4 sub-Saharan African regions (Eastern, Central, Southern, and Western).

RESULTS

Data were obtained from 65 surveys in 31 countries. In 2010, breastfeeding in the first month of life ("initial breastfeeding") among MLHIV ranged from 69.1% (95% credible interval: 68-79.9) in Southern Africa to 93.4% (92.7-98.0) in Western Africa. Median breastfeeding duration among MLHIV was the shortest in Southern Africa at 15.6 (14.2-16.3) months and the longest in Eastern Africa at 22.0 (21.7-22.5) months. By comparison, HIV-negative mothers were more likely to breastfeed initially (91.0%-98.7% across regions) and for longer duration (median 18.3-24.6 months across regions). Initial breastfeeding and median breastfeeding duration decreased during 2005-2015 in most regions and did not increase in any region regardless of maternal HIV status.

CONCLUSIONS

MLHIV in sub-Saharan Africa are less likely to breastfeed initially and stop breastfeeding sooner than HIV-negative mothers. Since 2020, UNAIDS-supported HIV estimates have accounted for this shorter breastfeeding exposure among HIV-exposed children. MLHIV need support to enable optimal breastfeeding practices and to adhere to antiretroviral therapy for HIV treatment and prevention of postnatal mother-to-child transmission.

Estimation of Improvements in Mortality in Spectrum Among Adults With HIV Receiving Antiretroviral Therapy in High-Income Countries

INTRODUCTION

Mortality rates for people living with HIV (PLHIV) on antiretroviral therapy (ART) in high-income countries continue to decline. We compared mortality rates among PLHIV on ART in Europe for 2016-2020 with Spectrum's estimates.

METHODS

The AIDS Impact Module in Spectrum is a compartmental HIV epidemic model coupled with a demographic population projection model. We used national Spectrum projections developed for the 2022 HIV estimates round to calculate mortality rates among PLHIV on ART, adjusting to the age/country distribution of PLHIV starting ART from 1996 to 2020 in the Antiretroviral Therapy Cohort Collaboration (ART-CC)'s European cohorts.

RESULTS

In the ART-CC, 11,504 of 162,835 PLHIV died. Between 1996-1999 and 2016-2020, AIDS-related mortality in the ART-CC decreased from 8.8 (95% CI: 7.6 to 10.1) to 1.0 (0.9-1.2) and from 5.9 (4.4-8.1) to 1.1 (0.9-1.4) deaths per 1000 person-years among men and women, respectively. Non-AIDS-related mortality decreased from 9.1 (7.9-10.5) to 6.1 (5.8-6.5) and from 7.0 (5.2-9.3) to 4.8 (4.3-5.2) deaths per 1000 person-years among men and women, respectively. Adjusted all-cause mortality rates in Spectrum among men were near ART-CC estimates for 2016-2020 (Spectrum: 7.02-7.47 deaths per 1000 person-years) but approximately 20% lower in women (Spectrum: 4.66-4.70). Adjusted excess mortality rates in Spectrum were 2.5-fold higher in women and 3.1-3.4-fold higher in men in comparison to the ART-CC's AIDS-specific mortality rates.

DISCUSSION

Spectrum's all-cause mortality estimates among PLHIV are consistent with age/country-controlled mortality observed in ART-CC, with some underestimation of mortality among women. Comparing results suggest that 60%-70% of excess deaths among PLHIV on ART in Spectrum are from non-AIDS causes.

Updated Data and Methods for the 2023 UNAIDS HIV Estimates

ABSTRACT

Each year, supported by the Joint United Nations Programme on HIV/AIDS (UNAIDS), country teams across the globe produce estimates that chart the state of their HIV epidemics. In 2023, HIV estimates were available for 174 countries, accounting for 99% of the global population, of which teams from 150 countries actively engaged in this process. The methods used to derive these estimates are developed under the guidance of the UNAIDS Reference Group on Estimates, Modeling, and Projections (www.epidem.org). Updates to these methods and epidemiological analyses that inform parameters and assumptions are documented in this supplement.

Augmenting progress on the elimination of vertical transmissions of HIV in India: Insights from Spectrum-based HIV burden estimations

The government of India has adopted the elimination of vertical transmission of HIV as one of the five high-level goals under phase V of the National AIDS and STD Control Programme (NACP). In this paper, we present the data from HIV estimations 2021 for India and select States detailing the progress as well as the attributable causes for vertical transmissions. The NACP spearheads work on mathematical modelling to estimate HIV burden based on the periodically conducted sentinel surveillance for guiding program implementation and policymaking. Using the results of the latest round of HIV Estimations in 2021, we analysed the mother-to-child transmission (MTCT) during the perinatal and postnatal (breastfeeding) period. In 2021, overall, around 5,000 [3,000-7,800] vertical transmissions were estimated nationally with 58% being perinatal infections and remaining during breastfeeding. MTCT at 6 weeks was around 12.95% [9.45-16.02] with the final transmission rate at 24.25% [18.50-29.50]. Overall, 57% of vertical transmissions were among HIV-positive mothers who did not receive ART during pregnancy or breastfeeding, 19% among mothers who dropped off ART during pregnancy or delivery, and 18% among mothers who were infected during pregnancy or breastfeeding. There were significant variations between States. Depending upon the States, the programme needs to focus on the intervention domains of timely engagement in antenatal care-HIV testing-ART initiation as well as programme retention and adherence support. Equally important would be strengthening the strategic information to generate related evidence for inputting India and State-specific parameters improving the MTCT-related modelled estimates.

Pediatric Antiretroviral Therapy Coverage and AIDS Deaths in the "Treat All" Era

OBJECTIVES

In 2015, CD4-based clinical staging criteria for antiretroviral therapy (ART) initiation were removed, expanding ART eligibility ("Treat All") for children, who shoulder an outsized burden of HIV-related deaths. To quantify the impact of "Treat All" on pediatric HIV outcomes, we examined shifts in pediatric ART coverage and AIDS mortality before and after "Treat All" implementation.

METHODS

We abstracted country-level ART coverage (proportion of children <15 years on ART) and AIDS mortality (deaths per 100 000 population) estimates over 11 years. For 91 countries, we also abstracted the year "Treat All" was incorporated into national guidelines. We used multivariable 2-way fixed effects negative binomial regression to estimate changes in pediatric ART coverage and AIDS mortality potentially attributable to "Treat All" expansion, reported as adjusted incidence rate ratios (adj.IRR) with 95% confidence intervals (95% CI).

RESULTS

From 2010 to 2020, pediatric ART coverage tripled (16% to 54%), and AIDS-related deaths were halved (240 000 to 99 000). Compared with the pre-implementation period, observed ART coverage continued increasing after "Treat All" adoption, but this rate of increase declined by 6% (adj.IRR = 0.94, 95% CI: 0.91-0.98). AIDS mortality continued declining after "Treat All" adoption, but this rate of decline decreased by 8% (adj.IRR = 1.08, 95% CI: 1.05-1.11) in the post-implementation period.

CONCLUSIONS

Although "Treat All" called for increased HIV treatment equity, ART coverage continues lagging in children and comprehensive approaches that address structural issues, including family-based services and intensified case-finding, are needed to close pediatric HIV treatment gaps.

Transmission modeling to infer tuberculosis incidence prevalence and mortality in settings with generalized HIV epidemics

Tuberculosis (TB) killed more people globally than any other single pathogen over the past decade. Where surveillance is weak, estimating TB burden estimates uses modeling. In many African countries, increases in HIV prevalence and antiretroviral therapy have driven dynamic TB epidemics, complicating estimation of burden, trends, and potential intervention impact. We therefore develop a novel age-structured TB transmission model incorporating evolving demographic, HIV and antiretroviral therapy effects, and calibrate to TB prevalence and notification data from 12 African countries. We use Bayesian methods to include uncertainty for all TB model parameters, and estimate age-specific annual risks of TB infection, finding up to 16.0%/year in adults, and the proportion of TB incidence from recent (re)infection, finding a mean across countries of 34%. Rapid reduction of the unacceptably high burden of TB in high HIV prevalence settings will require interventions addressing progression as well as transmission.

HIV Incidence, Recent HIV Infection, and Associated Factors, Kenya, 2007-2018

Nationally representative surveys provide an opportunity to assess trends in recent human immunodeficiency virus (HIV) infection based on assays for recent HIV infection. We assessed HIV incidence in Kenya in 2018 and trends in recent HIV infection among adolescents and adults in Kenya using nationally representative household surveys conducted in 2007, 2012, and 2018. To assess trends, we defined a recent HIV infection testing algorithm (RITA) that classified as recently infected (<12 months) those HIV-positive participants that were recent on the HIV-1 limiting antigen (LAg)-avidity assay without evidence of antiretroviral use. We assessed factors associated with recent and long-term (≥12 months) HIV infection versus no infection using a multinomial logit model while accounting for complex survey design. Of 1,523 HIV-positive participants in 2018, 11 were classified as recent. Annual HIV incidence was 0.14% in 2018 [95% confidence interval (CI) 0.057-0.23], representing 35,900 (95% CI 16,300-55,600) new infections per year in Kenya among persons aged 15-64 years. The percentage of HIV infections that were determined to be recent was similar in 2007 and 2012 but fell significantly from 2012 to 2018 [adjusted odds ratio (aOR) = 0.31, p < .001]. Compared to no HIV infection, being aged 25-34 versus 35-64 years (aOR = 4.2, 95% CI 1.4-13), having more lifetime sex partners (aOR = 5.2, 95% CI 1.6-17 for 2-3 partners and aOR = 8.6, 95% CI 2.8-26 for ≥4 partners vs. 0-1 partners), and never having tested for HIV (aOR = 4.1, 95% CI 1.5-11) were independently associated with recent HIV infection. Although HIV remains a public health priority in Kenya, HIV incidence estimates and trends in recent HIV infection support a significant decrease in new HIV infections from 2012 to 2018, a period of rapid expansion in HIV diagnosis, prevention, and treatment.

Cost-effectiveness of broadly neutralizing antibody prophylaxis for HIV-exposed infants in sub-Saharan African settings

INTRODUCTION

Infant HIV prophylaxis with broadly neutralizing anti-HIV antibodies (bNAbs) could provide long-acting protection against vertical transmission. We sought to estimate the potential clinical impact and cost-effectiveness of hypothetical bNAb prophylaxis programmes for children known to be HIV exposed at birth in three sub-Saharan African settings.

METHODS

We conducted a cost-effectiveness analysis using the CEPAC-Pediatric model, simulating cohorts of infants from birth through death in Côte d'Ivoire, South Africa and Zimbabwe. These settings were selected to reflect a broad range of HIV care cascade characteristics, antenatal HIV prevalence and budgetary constraints. We modelled strategies targeting bNAbs to only WHO-designated "high-risk" HIV-exposed infants (HR-HIVE) or to all HIV-exposed infants (HIVE). We compared four prophylaxis approaches within each target population: standard of care oral antiretroviral prophylaxis (SOC), and SOC plus bNAbs at birth (1-dose), at birth and 3 months (2-doses), or every 3 months throughout breastfeeding (Extended). Base-case model inputs included bNAb efficacy (60%/dose), effect duration (3 months/dose) and costs ($60/dose), based on published literature. Outcomes included paediatric HIV incidence and incremental cost-effectiveness ratios (ICERs) calculated from discounted life expectancy and lifetime HIV-related costs.

RESULTS

The model projects that bNAbs would reduce absolute infant HIV incidence by 0.3-2.2% (9.6-34.9% relative reduction), varying by country, prophylaxis approach and target population. In all three settings, HR-HIVE-1-dose would be cost-saving compared to SOC. Using a 50% GDP per capita ICER threshold, HIVE-Extended would be cost-effective in all three settings with ICERs of $497/YLS in Côte d'Ivoire, $464/YLS in South Africa and $455/YLS in Zimbabwe. In all three settings, bNAb strategies would remain cost-effective at costs up to $200/dose if efficacy is ≥30%. If the bNAb effect duration were reduced to 1 month, the cost-effective strategy would become HR-HIVE-1-dose in Côte d'Ivoire and Zimbabwe and HR-HIVE-2-doses in South Africa. Findings regarding the cost-effectiveness of bNAb implementation strategies remained robust in sensitivity analyses regarding breastfeeding duration, maternal engagement in postpartum care, early infant diagnosis uptake and antiretroviral treatment costs.

CONCLUSIONS

At current efficacy and cost estimates, bNAb prophylaxis for HIV-exposed children in sub-Saharan African settings would be a cost-effective intervention to reduce vertical HIV transmission.

Global HIV mortality trends among children on antiretroviral treatment corrected for under-reported deaths: an updated analysis of the International epidemiology Databases to Evaluate AIDS collaboration

INTRODUCTION

The Joint United Nations Programme on HIV/AIDS (UNAIDS) projections of paediatric HIV prevalence and deaths rely on the International epidemiology Databases to Evaluate AIDS (IeDEA) consortium for mortality estimates among children living with HIV (CHIV) receiving antiretroviral therapy (ART). Previous estimates, based on data through 2014, may no longer be accurate due to expanded paediatric HIV care and treatment eligibility, and the possibility of unreported deaths in CHIV considered lost to follow-up (LTFU). We therefore estimated all-cause mortality and its trends in CHIV (<15 years old) on ART using extended and new IeDEA data.

METHODS

We analysed (i) IeDEA observational data from CHIV in routine care globally, and (ii) novel data from an IeDEA tracing study that determined outcomes in a sample of CHIV after being LTFU in southern Africa. We included 45,711 CHIV on ART during 2004 to 2017 at 72 programmes in Africa, Asia-Pacific and Latin America. We used mixed effects Poisson regression to estimate mortality by age, sex, CD4 at ART start, time on ART, region and calendar year. For Africa, in an adjusted analysis that accounts for unreported deaths among those LTFU, we first modified the routine data by simulating mortality outcomes within six months after LTFU, based on a Gompertz survival model fitted to the tracing data (n = 221).

RESULTS

Observed mortality rates were 1.8 (95% CI: 1.7 to 1.9) and 9.4 (6.3 to 13.4) deaths per 100 person-years in the routine and tracing data, respectively. We found strong evidence of higher mortality at shorter ART durations, lower CD4 values, and in infancy. Averaging over covariate patterns, the adjusted mortality rate was 54% higher than the unadjusted rate. In unadjusted analyses, mortality reduced by an average 60% and 73% from 2005 to 2017, within and outside of Africa, respectively. In the adjusted analysis for Africa, this temporal reduction was 42%.

CONCLUSIONS

Mortality rates among CHIV have decreased substantially over time. However, when accounting for worse outcomes among those LTFU, mortality estimates increased and temporal improvements were slightly reduced, suggesting caution in interpreting analyses based only on programme data. The improved and updated IeDEA estimates on mortality among CHIV on ART support UNAIDS efforts to accurately model global HIV statistics.