The implementation of the 2013 World Health Organization Option B+ recommendations for HIV treatment during pregnancy has helped drive significant progress in achieving universal treatment for pregnant and postpartum women in sub-Saharan Africa (SSA). Yet, critical research and implementation gaps exist in achieving the UNAIDS 90-90-90 targets. To help guide researchers, programmers and policymakers in prioritising these areas, we undertook a comprehensive review of the progress, gaps and research needs to achieve the 90-90-90 targets for this population in the Option B+ era, including early infant HIV diagnosis (EID) for HIV-exposed infants. Salient areas where progress has been achieved or where gaps remain include: (1) knowledge of HIV status is higher among people with HIV in southern and eastern Africa compared to western and central Africa (81% versus 48%, UNAIDS); (2) access to antiretroviral therapy (ART) for pregnant women has doubled in 22 of 42 SSA countries, but only six have achieved the second 90, and nearly a quarter of pregnant women initiating ART become lost to follow-up; (3) viral suppression data for this population are sparse (estimates range from 30% to 98% peripartum), with only half of women maintaining suppression through 12 months postpartum; and (4) EID rates range from 15% to 62%, with only three of 21 high-burden SSA countries testing >50% HIV-exposed infants within the first 2 months of life. We have identified and outlined promising innovations and research designed to address these gaps and improve the health of pregnant and postpartum women living with HIV and their infants.

Background

Following a decline in perinatal HIV transmission from 20% to 10% between 2010 and 2017 in Kenya, rates have since plateaued with an estimated 8% transmission rate in 2021. Between October 2016 and September 2021, Family AIDS Care & Education Services (FACES) supported HIV care and treatment services across 61 facilities in Kisumu County, Kenya with an emphasis on service strengthening for pregnant and postpartum women living with HIV to reduce perinatal HIV transmission. This included rigorous implementation of national HIV guidelines and implementation of 3 locally adapted evidence-based interventions targeted to the unique needs of women and their infants. We examined whether these person-centered program enhancements were associated with changes in perinatal HIV transmission at FACES-supported sites over time.

Methods and findings

We conducted a repeated cross-sectional study of annually aggregated routinely collected documentation of perinatal HIV transmission risk through the end of breastfeeding at FACES-supported facilities between October 2016 and September 2021. Data included 12,599 women living with HIV with baseline antenatal care metrics, and, a separate data set of 11,879 mother-infant pairs who were followed from birth through the end of breastfeeding (overlapping with those in antenatal care 2 years prior). FACES implemented 3 interventions for pregnant and postpartum women living with HIV in 2019: (1) high-risk clinics; (2) case management; and (3) a mobile app to support treatment engagement. Our primary outcome was infant HIV acquisition by the end of breastfeeding (18 to 24 months). We compared infant HIV acquisition risk in the final year of the FACES program (2021) to the year before intervention scale-up and following implementation of the "Treat All" policy (2018). Mother-infant pair loss to follow-up was a secondary outcome. Program data were aggregated by year and site, thus in multivariable regression, we adjusted for site-level characteristics, including facility type, urban versus rural, number of women with HIV in antenatal care each year, and the proportion among them under 25 years of age. Between October 2016 and September 2021, 81,172 pregnant women received HIV testing at the initiation of antenatal care, among whom 12,599 (15.5%) were living with HIV, with little variation in HIV prevalence over time. The risk of infant HIV acquisition by 24 months of age declined from 4.9% (101/2,072) in 2018 to 2.2% (48/2,156) in 2021 (adjusted risk difference -2.6% [95% confidence interval (CI): -3.7, -1.6]; p < 0.001). Loss to follow-up declined from 9.9% (253/2,556) in 2018 to 2.5% (59/2,393) in 2021 (risk difference -7.5% [95% CI: -8.8, -6.2]; p < 0.001). During the same period, UNAIDS estimated rates of perinatal transmission in the broader Nyanza region and in Kenya as a whole did not decline. The main limitation of this study is that we lacked a comparable control group.

Conclusions

These findings suggest that implementation of person-centered interventions was associated with significant declines in perinatal HIV transmission and loss to follow-up of pregnant and postpartum women.

Introduction

Prevention of mother-to-child HIV transmission (PMTCT) strategies include combined short-course antiretrovirals during pregnancy (Option A), triple-drug antiretroviral treament (ART) during pregnancy and breastfeeding (Option B), or lifelong ART (Option B+). The WHO also recommends ART for HIV treatment and prevention of sexual transmission of HIV. The impact of PMTCT strategies on prevention of sexual HIV transmission of HIV is not known. We estimated the population-level impact of PMTCT interventions on heterosexual HIV transmission in southwestern Uganda and KwaZulu-Natal, South Africa, two regions with different HIV prevalence and fertility rates.

Materials and methods

We constructed and validated dynamic, stochastic, network-based HIV transmission models for each region. PMTCT Options A, B, and B+ were simulated over ten years under three scenarios: 1) current ART and PMTCT coverage, 2) current ART and high PMTCT coverage, and 3) high ART and PMTCT coverage. We compared adult HIV incidence after ten years of each intervention to Option A (and current ART) at current coverage.

Results

At current coverage, Options B and B+ reduced heterosexual HIV incidence by about 5% and 15%, respectively, in both countries. With current ART and high PMTCT coverage, Option B+ reduced HIV incidence by 35% in Uganda and 19% in South Africa, while Option B had smaller, but meaningful, reductions. The greatest reductions in HIV incidence were achieved with high ART and PMTCT coverage. In this scenario, all PMTCT strategies yielded similar results.

Discussion

Implementation of Options B/B+ reduces adult HIV incidence, with greater effect (relative to Option A at current levels) in Uganda than South Africa. These results are likely driven by Uganda's higher fertility rates.

Objective

We examined whether human mobility was associated with antiretroviral treatment adherence, measured via antiretroviral hair concentrations.

Design

This is a cross-sectional analysis of adults on antiretroviral treatment in East Africa at baseline in an observational cohort study.

Methods

Participants reported recent mobility (overnight travel) and histories of migration (changes of residence), including reasons, frequency/duration, and locations. Hair antiretroviral concentrations were analyzed using validated methods. We estimated associations between mobility and antiretroviral concentrations via linear regression adjusted for age, sex, region, years on treatment.

Results

Among 383 participants, half were women and the median age was 40. Among men, 25% reported recent work-related mobility, 30% nonwork mobility, and 11% migrated in the past year (mostly across district boundaries); among women, 6 and 57% reported work-related and nonwork mobility, respectively, and 8% recently migrated (mostly within district). Those reporting work-related trips 2 nights or less had 72% higher hair antiretroviral levels (P = 0.02) than those who did not travel for work; in contrast, nonwork mobility (any duration, vs. none) was associated with 24% lower levels (P = 0.06). Intra-district migrations were associated with 59% lower antiretroviral levels than nonmigrants (P = 0.003) while inter-district migrations were not (27% higher, P = 0.40).

Conclusion

We found that localized/intra-district migration and nonwork travel-more common among women-were associated with lower adherence, potentially reflecting care interruptions or staying with family/friends unaware of the participants' status. In contrast, short work-related trips-more common among men-were associated with higher adherence, perhaps reflecting higher income. Adherence interventions may require tailoring by sex and forms of mobility.

Introduction

Human mobility is a critical aspect of existence and survival, but may compromise care engagement among people living with HIV (PLHIV). We examined the association between various forms of human mobility with retention in HIV care and antiretroviral treatment (ART) interruptions.

Methods

In a cohort of adult PLHIV in Kenya and Uganda, we collected surveys in 2016 about past 6-month travel and lifetime migration histories, including reasons and locations, and engagement in HIV care defined as (1) discontinuation of care, and (2) history of a treatment interruption among those who remained in care. We estimated associations between mobility and these care engagement outcomes via logistic regression, adjusted for sex, prior mobility, age, region, marital status, household wealth, and education.

Results

Among 1081 participants, 56 (5%) reported having discontinued care; among those in care, 104 (10%) reported treatment interruption. Past-year migration was associated with a higher risk of discontinuation of care (adjusted odds ratio [aOR] 1.98, 95% CI 1.08-3.63). In sex-stratified models, the association was somewhat attenuated in women, but remained robust among men. Past-year migration was associated with reduced odds of having a treatment interruption among men (aOR 0.51, 95% CI 0.34-0.77) but not among women (aOR 2.67, 95% CI 0.78, 9.16). Travel in the past 6 months was not associated with discontinuation of care or treatment interruptions.

Conclusions

We observed both negative and protective effects of recent migration on care engagement and ART use that were most pronounced among men in this cohort. Migration can break ties to ongoing care, but for men, who have more agency in the decision to migrate, may foster new care and treatment strategies. Strategies that enable health facilities to support individuals throughout the process of transferring care could alleviate the risk of care disengagement.

Background

Antiretroviral treatment (ART) adherence is often suboptimal in the perinatal period. We measured hair tenofovir (TFV) concentrations as a metric of adherence in postpartum women to understand patterns and predictors of adherence throughout this critical period. In addition, we examined the association between hair TFV concentrations and virologic outcomes.

Methods

Between 12/2012 and 09/2016, hair samples were collected longitudinally from delivery through breastfeeding from women on ART in the Promoting Maternal and Infant Survival Everywhere study (NCT01061151) in sub-Saharan Africa. Hair TFV levels were measured using validated methods. Using generalized estimating equations, we estimated the association between hair TFV levels and virologic suppression (<400 copies/ml) over time and assessed predictors of hair TFV levels.

Results

Hair TFV levels were measured at 370 visits in 71 women from delivery through a median of 14 months (interquartile range 12-15) of breastfeeding. Levels ranged from below detection (0.002) to 1.067 ng/mg (geometric mean: 0.047). After at least 90 days on ART, 69 women had at least one viral load measured (median 5 measures, range 1-9); 18 (26%) experienced viremia at least once. Each doubling of TFV level more than doubled odds of concurrent virologic suppression [odds ratio 2.35, 95% confidence interval (CI): 1.44-3.84, P = 0.0006] and was associated with 1.43 times the odds of future suppression (95% CI: 0.75-2.73, P = 0.28). Relative to the first 3 months after delivery, hair levels were highest in months 6-12 (1.42-fold higher, 95% CI: 1.09-1.85, P = 0.01).

Conclusion

Hair TFV levels strongly predicted concurrent virologic suppression among breastfeeding women. Objective adherence metrics can supplement virologic monitoring to optimize treatment outcomes in this important transition period.

Introduction

Prevention of mother-to-child HIV transmission (PMTCT) strategies include combined short-course antiretrovirals during pregnancy (Option A), triple-drug antiretroviral treament (ART) during pregnancy and breastfeeding (Option B), or lifelong ART (Option B+). The WHO also recommends ART for HIV treatment and prevention of sexual transmission of HIV. The impact of PMTCT strategies on prevention of sexual HIV transmission of HIV is not known. We estimated the population-level impact of PMTCT interventions on heterosexual HIV transmission in southwestern Uganda and KwaZulu-Natal, South Africa, two regions with different HIV prevalence and fertility rates.

Materials and methods

We constructed and validated dynamic, stochastic, network-based HIV transmission models for each region. PMTCT Options A, B, and B+ were simulated over ten years under three scenarios: 1) current ART and PMTCT coverage, 2) current ART and high PMTCT coverage, and 3) high ART and PMTCT coverage. We compared adult HIV incidence after ten years of each intervention to Option A (and current ART) at current coverage.

Results

At current coverage, Options B and B+ reduced heterosexual HIV incidence by about 5% and 15%, respectively, in both countries. With current ART and high PMTCT coverage, Option B+ reduced HIV incidence by 35% in Uganda and 19% in South Africa, while Option B had smaller, but meaningful, reductions. The greatest reductions in HIV incidence were achieved with high ART and PMTCT coverage. In this scenario, all PMTCT strategies yielded similar results.

Discussion

Implementation of Options B/B+ reduces adult HIV incidence, with greater effect (relative to Option A at current levels) in Uganda than South Africa. These results are likely driven by Uganda's higher fertility rates.

Stress and food insecurity (FI) are associated with poor perinatal and HIV outcomes. We hypothesized that FI would increase postpartum stress among women in Kenya, and that the impact would be greater in women with HIV. Among 371 pregnant women, we identified latent FI trajectories across the perinatal period, and estimated their association with postpartum stress. Stress metrics included the Perceived Stress Scale (PSS) and hair cortisol concentrations (HCC). We identified two FI trajectories: persistent moderate FI and persistent mild FI. Moderate FI (vs. mild) was associated with higher PSS; this association was stronger among HIV-negative women. We observed a trend towards higher HCC associated with moderate FI, which did not differ by HIV status. HCC and PSS were not correlated. In summary, moderate FI (vs. mild) was associated with increased stress. The lack of PSS-HCC correlation could reflect different physiological pathways. Interventions to mitigate FI could alleviate postpartum stress.

Background

We examined change in antiretroviral treatment (ART) adherence after breastfeeding (BF) cessation using hair tenofovir (TFV) concentrations as an objective metric of medication consumption.

Methods

A subset of postpartum women in Zimbabwe randomized in IMPAACT PROMISE to take ART while BF and post-BF cessation had hair TFV measured longitudinally. Using linear mixed-effect models, we estimated differences in hair TFV levels after BF cessation, accounting for trends in levels over time regardless of BF status and change in slope after breastfeeding cessation. We also estimated the relative risk of viremia (>50 copies/mL) per doubling of hair TFV concentration.

Results

Among 55 women (median age 26, interquartile range 24-29 years), hair TFV levels (n = 305) were available for a median of 9 visits per woman between 3 and 29 months postpartum. Hair TFV levels ranged from undetected to 0.25 ng/mg (median 0.04 ng/mg). Controlling for trends since delivery [decline of 2.2% per month, 95% confidence interval (CI): -5.3 to 1.0], TFV levels averaged 24.4% higher (95% CI: -5.1 to 63.1) post-BF cessation than during BF, with no change in slope (0.0% per month, 95% CI: -3.8 to 3.9). Postpartum, 42% of women were ever viremic. Higher TFV levels were strongly protective; relative risk of viremia per doubling of TFV was 0.52 (95% CI: 0.43 to 0.63; P < 0.0001).

Conclusions

Leveraging an objective metric of ART use, we observed modestly declining adherence across the postpartum period, but no additional decline associated with breastfeeding cessation. High viremia frequency and varying postpartum TFV levels observed highlight the importance of enhanced adherence support with viral load monitoring among postpartum women.

Background

Adherence to antiretroviral treatment (ART) among postpartum women with HIV is essential for optimal health and prevention of perinatal transmission. However, suboptimal adherence with subsequent viremia is common, and adherence challenges are often underreported. We aimed to predict viremia to facilitate targeted adherence support in sub-Saharan Africa during this critical period.

Methods

Data are from PROMISE 1077BF/FF, which enrolled perinatal women between 2011 and 2014. This analysis includes postpartum women receiving ART per study randomization or country-specific criteria to continue from pregnancy. We aimed to predict viremia (single and confirmed events) after 3 months on ART at >50, >400, and >1000 copies/mL within 6-month intervals through 24 months. We built models with routine clinical and demographic data using the least absolute shrinkage and selection operator and SuperLearner (which incorporates multiple algorithms).

Results

Among 1321 women included, the median age was 26 years and 96% were in WHO stage 1. Between 0 and 24 months postpartum, 42%, 31%, and 28% of women experienced viremia >50, >400, and >1000 copies/mL, respectively, at least once. Across models, the cross-validated area under the receiver operating curve ranged from 0.74 [95% confidence interval (CI): 0.72 to 0.76] to 0.78 (95% CI: 0.76 to 0.80). To achieve 90% sensitivity predicting confirmed viremia >50 copies/mL, 64% of women would be classified as high risk.

Conclusions

Using routinely collected data to predict viremia in >1300 postpartum women with HIV, we achieved moderate model discrimination, but insufficient to inform targeted adherence support. Psychosocial characteristics or objective adherence metrics may be required for improved prediction of viremia in this population.