What will it take to eliminate pediatric HIV? Reaching WHO target rates of mother-to-child HIV transmission in Zimbabwe: a model-based analysis

Understanding the Immune System in Fetal Protection and Maternal Infections during Pregnancy

The fetal-maternal immune system determines the fate of pregnancy. The trophoblast cells not only give an active response against external stimuli but are also involved in secreting most of the cytokines. These cells have an essential function in fetal acceptance or fetal rejection. Other immune cells also play a pivotal role in carrying out a successful pregnancy. The disruption in this mechanism may lead to harmful effects on pregnancy. The placenta serves as an immune barrier in fetus protection against invading pathogens. Once the infections prevail, they may localize in placental and fetal tissues, and the presence of inflammation due to cytokines may have detrimental effects on pregnancy. Moreover, some pathogens are responsible for congenital fetal anomalies and affect almost all organs of the developing fetus. This review article is designed to address the bacterial and viral infections that threaten pregnancy and their possible outcomes. Moreover, training of the fetal immune system against the exposure of infections and the role of CD49a + NK cells in embryonic development will also be highlighted.

Integration of Early Infant Diagnosis of HIV Services Into Village Health Clinics in Ntcheu, Malawi: An Exploratory Qualitative Study

Integration of Early Infant Diagnosis(EID) of HIV into Village Health Clinics (VHCs) would increase the uptake of services. This study assessed mothers and health care workers' acceptability of integration of EID of HIV services into VHCs in Ntcheu, Malawi. We conducted an exploratory qualitative study in the phenomenological tradition among 20 mothers of either HIV exposed or non-exposed infants and 18 health care workers (HCWs) from February to July 2019. We analyzed the data using a thematic approach and guided by the theoretical framework for acceptability. There were positive perceptions of the integration of services. Acceptability is influenced by attitudes, perceived burden, intervention coherent services, and perceived effectiveness of services. The successful integration of EID of HIV into VHCs requires strengthening of the health system and community awareness. Efforts to mitigate stigma should be prioritized when integrating the services to optimize uptake of the services at a community level.

Marginal Effects of Systemic CCR5 Blockade with Maraviroc on Oral Simian Immunodeficiency Virus Transmission to Infant Macaques

Current approaches do not eliminate all human immunodeficiency virus type 1 (HIV-1) maternal-to-infant transmissions (MTIT); new prevention paradigms might help avert new infections. We administered maraviroc (MVC) to rhesus macaques (RMs) to block CCR5-mediated entry, followed by repeated oral exposure of a CCR5-dependent clone of simian immunodeficiency virus (SIV) mac251 (SIVmac766). MVC significantly blocked the CCR5 coreceptor in peripheral blood mononuclear cells and tissue cells. All control animals and 60% of MVC-treated infant RMs became infected by the 6th challenge, with no significant difference between the number of exposures (P = 0.15). At the time of viral exposures, MVC plasma and tissue (including tonsil) concentrations were within the range seen in humans receiving MVC as a therapeutic. Both treated and control RMs were infected with only a single transmitted/founder variant, consistent with the dose of virus typical of HIV-1 infection. The uninfected RMs expressed the lowest levels of CCR5 on the CD4+ T cells. Ramp-up viremia was significantly delayed (P = 0.05) in the MVC-treated RMs, yet peak and postpeak viral loads were similar in treated and control RMs. In conclusion, in spite of apparent effective CCR5 blockade in infant RMs, MVC had a marginal impact on acquisition and only a minimal impact on the postinfection delay of viremia following oral SIV infection. Newly developed, more effective CCR5 blockers may have a more dramatic impact on oral SIV transmission than MVC.IMPORTANCE We have previously suggested that the very low levels of simian immunodeficiency virus (SIV) maternal-to-infant transmissions (MTIT) in African nonhuman primates that are natural hosts of SIVs are due to a low availability of target cells (CCR5+ CD4+ T cells) in the oral mucosa of the infants, rather than maternal and milk factors. To confirm this new MTIT paradigm, we performed a proof-of-concept study in which we therapeutically blocked CCR5 with maraviroc (MVC) and orally exposed MVC-treated and naive infant rhesus macaques to SIV. MVC had only a marginal effect on oral SIV transmission. However, the observation that the infant RMs that remained uninfected at the completion of the study, after 6 repeated viral challenges, had the lowest CCR5 expression on the CD4+ T cells prior to the MVC treatment appears to confirm our hypothesis, also suggesting that the partial effect of MVC is due to a limited efficacy of the drug. New, more effective CCR5 inhibitors may have a better effect in preventing SIV and HIV transmission.

Evaluating Facility Infrastructure for Prevention of Mother-to-Child Transmission of HIV-A 2015 Assessment of Major Delivery Hospitals in Atlanta, Georgia

OBJECTIVE

Our goal was to evaluate the infrastructure of programs for the prevention of mother-to-child transmission (PMTCT) of human immunodeficiency virus (HIV) in major delivery units in the Atlanta, Georgia, metropolitan statistical area and to assess the knowledge, attitude, and practice of providers in these facilities around PMTCT.

METHODS

Hospital assessments and individual knowledge and practices were surveyed among 71 healthcare providers from March 2015 to March 2016 in 11 hospitals that deliver 40000 infants annually, which represents 70% of all deliveries in the Atlanta metropolitan statistical area. Included were questions about HIV testing for mother-infant pairs, test result turnaround times, policies and procedures for PMTCT, opt-out versus opt-in testing, availability of rapid point-of-care testing on labor and delivery units, and postnatal prophylaxis.

RESULTS

Seventy-three percent (8 of 11) of the hospitals had limitations in their PMTCT infrastructure, and 36% (4 of 11) reported no standardized policies for care of HIV-infected women. Three labor and delivery units used opt-in HIV testing of women. Only 27% (3 of 11) of the hospitals reported nucleic acid testing of HIV-exposed infants. Oral zidovudine for infant prophylaxis was available in all the hospitals, but 64% (7 of 11) of them did not stock nevirapine. Fifty-nine percent (24 of 44) of the obstetricians did not routinely offer rapid testing at delivery without a third-trimester HIV test, and 78% (n = 32 of 41) of them did not offer testing at delivery if the woman declined antenatal testing. The facility with the most annual births in Georgia did not offer rapid testing at delivery for women with an unknown HIV status.

CONCLUSION

We identified several limitations in PMTCT infrastructure that might have contributed to perinatal HIV transmissions. The need to address these healthcare gaps to eliminate mother-to-child transmission of HIV in the United States is urgent.

Eliminating Mother-to-Child Transmission of HIV by 2030: 5 Strategies to Ensure Continued Progress

To keep up momentum in preventing mother-to-child transmission we propose: (1) advocating for greater political and financial commitment; (2) targeting high-risk populations such as adolescent girls and young women; (3) implementing novel service delivery models such as community treatment groups; (4) performing regular viral load monitoring during pregnancy and postpartum to ensure suppression before delivery and during breastfeeding; and (5) harnessing technology in monitoring and evaluation and HIV diagnostics.

Utilization of prevention of mother-to-child transmission (PMTCT) services among pregnant women in HIV care in Uganda: a 24-month cohort of women from pre-conception to post-delivery

Objective

We assessed the uptake of prevention of mother-to-child transmission (PMTCT) services in a cohort of HIV infected women in care at The AIDS Support Organization Jinja and Kampala in Uganda, who were trying to conceive, over a period of 24 months, to inform the strengthening of PMTCT service access for women in care.

Results

Of the 299 women 127 (42.5%) reported at least one pregnancy within 24 months; 61 women (48.0%) delivered a live child. Of the 55 who had a live birth at the first pregnancy, 54 (98.2%) used antenatal care (ANC) starting at 15.5 weeks of gestation on average and 47/49 (95.9%) delivered at a health facility. Excluding miscarriages, 54 (98.2%) received ARVs during pregnancy. Of the 49 live births with post-delivery data, 37 (75.5%) tested the infant for HIV. 79 of the 127 (68.7%) spoke with providers about childbearing. Communication with providers was associated with ANC use (65.8% vs. 41.7%; p = .015). Despite the high rate of miscarriages and late ANC start, this study shows very high uptake of PMTCT services among PLHIV in care and their infants. Improved provider–client communication could enhance ANC attendance and PMTCT outcomes among HIV infected women in care.

Prevention of mother-to-child transmission of HIV: a cross-sectional study in Malawi

Objective

To estimate the use and outcomes of the Malawian programme for the prevention of mother-to-child transmission (MTCT) of human immunodeficiency virus (HIV).

Methods

In a cross-sectional analysis of 33 744 mother–infant pairs, we estimated the weighted proportions of mothers who had received antenatal HIV testing and/or maternal antiretroviral therapy and infants who had received nevirapine prophylaxis and/or HIV testing. We calculated the ratios of MTCT at 4–26 weeks postpartum for subgroups that had missed none or at least one of these four steps.

Findings

The estimated uptake of antenatal testing was 97.8%; while maternal antiretroviral therapy was 96.3%; infant prophylaxis was 92.3%; and infant HIV testing was 53.2%. Estimated ratios of MTCT were 4.7% overall and 7.7% for the pairs that had missed maternal antiretroviral therapy, 10.7% for missing both maternal antiretroviral therapy and infant prophylaxis and 11.4% for missing maternal antiretroviral therapy, infant prophylaxis and infant testing. Women younger than 19 years were more likely to have missed HIV testing (adjusted odds ratio, aOR: 4.9; 95% confidence interval, CI: 2.3–10.6) and infant prophylaxis (aOR: 6.9; 95% CI: 1.2–38.9) than older women. Women who had never started maternal antiretroviral therapy were more likely to have missed infant prophylaxis (aOR: 15.4; 95% CI: 7.2–32.9) and infant testing (aOR: 13.7; 95% CI: 4.2–83.3) than women who had.

Conclusion

Most women used the Malawian programme for the prevention of MTCT. The risk of MTCT increased if any of the main steps in the programme were missed.

The value of confirmatory testing in early infant HIV diagnosis programmes in South Africa: A cost-effectiveness analysis

BACKGROUND

The specificity of nucleic acid amplification tests (NAATs) used for early infant diagnosis (EID) of HIV infection is <100%, leading some HIV-uninfected infants to be incorrectly identified as HIV-infected. The World Health Organization recommends that infants undergo a second NAAT to confirm any positive test result, but implementation is limited. Our objective was to determine the impact and cost-effectiveness of confirmatory HIV testing for EID programmes in South Africa.

METHOD AND FINDINGS

Using the Cost-effectiveness of Preventing AIDS Complications (CEPAC)-Pediatric model, we simulated EID testing at age 6 weeks for HIV-exposed infants without and with confirmatory testing. We assumed a NAAT cost of US$25, NAAT specificity of 99.6%, NAAT sensitivity of 100% for infants infected in pregnancy or at least 4 weeks prior to testing, and a mother-to-child transmission (MTCT) rate at 12 months of 4.9%; we simulated guideline-concordant rates of testing uptake, result return, and antiretroviral therapy (ART) initiation (100%). After diagnosis, infants were linked to and retained in care for 10 years (false-positive) or lifelong (true-positive). All parameters were varied widely in sensitivity analyses. Outcomes included number of infants with false-positive diagnoses linked to ART per 1,000 ART initiations, life expectancy (LE, in years) and per-person lifetime HIV-related healthcare costs. Both without and with confirmatory testing, LE was 26.2 years for HIV-infected infants and 61.4 years for all HIV-exposed infants; clinical outcomes for truly infected infants did not differ by strategy. Without confirmatory testing, 128/1,000 ART initiations were false-positive diagnoses; with confirmatory testing, 1/1,000 ART initiations were false-positive diagnoses. Because confirmatory testing averted costly HIV care and ART in truly HIV-uninfected infants, it was cost-saving: total cost US$1,790/infant tested, compared to US$1,830/infant tested without confirmatory testing. Confirmatory testing remained cost-saving unless NAAT cost exceeded US$400 or the HIV-uninfected status of infants incorrectly identified as infected was ascertained and ART stopped within 3 months of starting. Limitations include uncertainty in the data used in the model, which we examined with sensitivity and uncertainty analyses. We also excluded clinical harms to HIV-uninfected infants incorrectly treated with ART after false-positive diagnosis (e.g., medication toxicities); including these outcomes would further increase the value of confirmatory testing.

CONCLUSIONS

Without confirmatory testing, in settings with MTCT rates similar to that of South Africa, more than 10% of infants who initiate ART may reflect false-positive diagnoses. Confirmatory testing prevents inappropriate HIV diagnosis, is cost-saving, and should be adopted in all EID programmes.

"If donors woke up tomorrow and said we can't fund you, what would we do?" A health system dynamics analysis of implementation of PMTCT option B+ in Uganda

Background

In October 2012 Uganda extended its prevention of mother to child HIV transmission (PMTCT) policy to Option B+, providing lifelong antiretroviral treatment for HIV positive pregnant and breastfeeding women. The rapid changes and adoptions of new PMTCT policies have not been accompanied by health systems research to explore health system preparedness to implement such programmes. The implementation of Option B+ provides many lessons which can inform the shift to ‘Universal Test and Treat’, a policy which many sub-Saharan African countries are preparing to adopt, despite fragile health systems.

Methods

This qualitative study of PMTCT Option B+ implementation in Uganda three years following the policy adoption, uses the health system dynamics framework to explore the impacts of this programme on ten elements of the health system. Qualitative data were gathered through rapid appraisal during in-country field work. Key informant interviews and focus group discussions (FGDs) were undertaken with the Ministry of Health, implementing partners, multilateral agencies, district management teams, facility-based health workers and community cadres. A total of 82 individual interviews and 16 focus group discussions were completed. We conducted a simple manifest analysis, using the ten elements of a health system for grouping data into categories and themes.

Results

Of the ten elements in the health system dynamics framework, context and resources (finances, infrastructure & supplies, and human resources) were the most influential in the implementation of Option B+ in Uganda. Support from international actors and implementing partners attempted to strengthen resources at district level, but had unintended consequences of creating dependence and uncertainty regarding sustainability.

Conclusions

The health system dynamics framework offers a novel approach to analysis of the effects of implementation of a new policy on critical elements of the health system. Its emphasis on relationships between system elements, population and context is helpful in unpacking impacts of and reactions to pressures on the system, which adds value beyond some previous frameworks.

The unique immunological and microbial aspects of pregnancy

The comparison of the immunological state of pregnancy to an immunosuppressed host-graft model continues to lead research and clinical practice to ill-defined approaches. This Review discusses recent evidence that supports the idea that immunological responses at the receptive maternal-fetal interface are not simply suppressed but are instead highly dynamic. We discuss the crucial role of trophoblast cells in shaping not only the way in which immune cells respond to the invading blastocyst but also how they collectively react to external stimuli. We also discuss the role of the microbiota in promoting a tolerogenic maternal immune system and highlight how subclinical viral infections can disrupt this status quo, leading to pregnancy complications.

Conditional Cash Transfers Improve Retention in PMTCT Services by Mitigating the Negative Effect of Not Having Money to Come to the Clinic

OBJECTIVE

To elucidate the mechanisms by which a cash incentive intervention increases retention in prevention of mother-to-child transmission services.

METHODS

We used data from a randomized controlled trial in Kinshasa, Democratic Republic of Congo. Perceptual factors associated with loss to follow-up (LTFU) through 6 weeks postpartum were first identified. Then, binomial models were used to assess interactions between LTFU and identified factors, and the cash incentive intervention.

RESULTS

Participants were less likely to be LTFU if they perceived HIV as a "very serious" health problem for their baby vs. not [risk difference (RD), -0.13; 95% confidence interval (CI): -0.30 to 0.04], if they believed it would be "very likely" to pass HIV to their baby if they did not take any HIV drug vs. not (RD, -0.15; 95% CI: -0.32 to 0.02), and if they anticipated that not having money would make it difficult for them to come to the clinic vs. not (RD, 0.12; 95% CI: -0.07 to 0.30). The effect of each of the 3 factors on LTFU was antagonistic to that of receiving the cash incentive intervention. The excess risk due to interaction between the cash incentive intervention and the anticipated difficulty of "not having money" to come to the clinic was exactly equal to the effect of removing this perceived barrier (excess risk due to interaction, -0.12; 95% CI: -0.35 to 0.10).

CONCLUSIONS

Our analyses show that cash transfers improve retention in prevention of mother-to-child transmission services mainly by mitigating the negative effect of not having money to come to the clinic.

Operations research in global health: a scoping review with a focus on the themes of health equity and impact

BACKGROUND

Operations research (OR) is a discipline that uses advanced analytical methods (e.g. simulation, optimisation, decision analysis) to better understand complex systems and aid in decision-making. Herein, we present a scoping review of the use of OR to analyse issues in global health, with an emphasis on health equity and research impact. A systematic search of five databases was designed to identify relevant published literature. A global overview of 1099 studies highlights the geographic distribution of OR and common OR methods used. From this collection of literature, a narrative description of the use of OR across four main application areas of global health - health systems and operations, clinical medicine, public health and health innovation - is also presented. The theme of health equity is then explored in detail through a subset of 44 studies. Health equity is a critical element of global health that cuts across all four application areas, and is an issue particularly amenable to analysis through OR. Finally, we present seven select cases of OR analyses that have been implemented or have influenced decision-making in global health policy or practice. Based on these cases, we identify three key drivers for success in bridging the gap between OR and global health policy, namely international collaboration with stakeholders, use of contextually appropriate data, and varied communication outlets for research findings. Such cases, however, represent a very small proportion of the literature found.

CONCLUSION

Poor availability of representative and quality data, and a lack of collaboration between those who develop OR models and stakeholders in the contexts where OR analyses are intended to serve, were found to be common challenges for effective OR modelling in global health.

Clinical Impact and Cost-effectiveness of Diagnosing HIV Infection During Early Infancy in South Africa: Test Timing and Frequency

BACKGROUND

 Diagnosis of human immunodeficiency virus (HIV) infection during early infancy (commonly known as "early infant HIV diagnosis" [EID]) followed by prompt initiation of antiretroviral therapy dramatically reduces mortality. EID testing is recommended at 6 weeks of age, but many infant infections are missed.

DESIGN/METHODS

 We simulated 4 EID testing strategies for HIV-exposed infants in South Africa: no EID (diagnosis only after illness; hereafter, "no EID"), testing once (at birth alone or at 6 weeks of age alone; hereafter, "birth alone" and "6 weeks alone," respectively), and testing twice (at birth and 6 weeks of age; hereafter "birth and 6 weeks"). We calculated incremental cost-effectiveness ratios (ICERs), using discounted costs and life expectancies for all HIV-exposed (infected and uninfected) infants.

RESULTS

 In the base case (guideline-concordant care), the no EID strategy produced a life expectancy of 21.1 years (in the HIV-infected group) and 61.1 years (in the HIV-exposed group); lifetime cost averaged $1430/HIV-exposed infant. The birth and 6 weeks strategy maximized life expectancy (26.5 years in the HIV-infected group and 61.4 years in the HIV-exposed group), costing $1840/infant tested. The ICER of the 6 weeks alone strategy versus the no EID strategy was $1250/year of life saved (19% of South Africa's per capita gross domestic product); the ICER for the birth and 6 weeks strategy versus the 6 weeks alone strategy was $2900/year of life saved (45% of South Africa's per capita gross domestic product). Increasing the proportion of caregivers who receive test results and the linkage of HIV-positive infants to antiretroviral therapy with the 6 weeks alone strategy improved survival more than adding a second test.

CONCLUSIONS

 EID at birth and 6 weeks improves outcomes and is cost-effective, compared with EID at 6 weeks alone. If scale-up costs are comparable, programs should add birth testing after strengthening 6-week testing programs.

Predictors of Patient Dissatisfaction with Services for Prevention of Mother-To-Child Transmission of HIV in Dar es Salaam, Tanzania

Background

Mother-to-child transmission (MTCT) of HIV remains a major source of new HIV infections in children. Prevention of mother-to-child transmission of HIV (PMTCT) using lifelong antiretroviral treatment (ART) for all pregnant and breastfeeding women living with HIV (Option B+) is the major strategy for eliminating paediatric HIV. Ensuring that patients are satisfied with PMTCT services is important for optimizing uptake, adherence and retention in treatment.

Methods

We conducted a facility based quantitative cross-sectional survey in Dar-es-Salaam, Tanzania, between March and April 2014, when the country was transitioning to the implementation of PMTCT Option B+. We interviewed 595 pregnant and breastfeeding women living with HIV, who received PMTCT care in 36 public health facilities. Predictors of overall dissatisfaction with PMTCT services were identified using a multiple logistic regression.

Results

Overall 8% of the patients expressed dissatisfaction with PMTCT services. Patients who perceived health care workers (HCW) communication skills as poor, had a 5-fold (OR 4.9, 95% CI 1.8–13.4) increased risk of dissatisfaction and those who perceived HCW capacity to understand client concerns as poor, had a 6-fold (OR 5.7, 95% CI 2.3–14.0) increased risk. Having a total visit time longer than two hours was associated with a 2-fold increased risk of being dissatisfied (OR 2.3, 95% CI 1.1–4.7). Every 30-minute increment in total visit time was associated with a 10% higher (OR 1.1, 95% CI 1.0–1.2) risk of being dissatisfied. The probability of being dissatisfied ranged from 4% (95% CI 2% - 6%) in the presence of patient-perceived good communication, good understanding of patient concerns, and a total visit time below two hours, to 70% (95% CI 47% - 86%) if HCW failed in all of these aspects.

Conclusion

Patient dissatisfaction with PMTCT services was generally low; reflecting that quality of care was maintained during Tanzania’s transition to Option B+ strategy aiming to increase the number of women initiating life-long ART in PMTCT clinics. Improved HCW communication with clients, their understanding of patient concerns and a reduction of the total visit time would further optimize women’s overall satisfaction with PMTCT services in Tanzania.

Reassuring Birth Outcomes With Tenofovir/Emtricitabine/Efavirenz Used for Prevention of Mother-to-Child Transmission of HIV in Botswana

BACKGROUND

Before introduction of tenofovir/emtricitabine/efavirenz (TDF/FTC/EFV), 3-drug antiretroviral therapy (ART) was associated with increased adverse birth outcomes when used for prevention of mother-to-child HIV transmission (PMTCT) in Botswana.

METHODS

We extracted obstetric records from all women at the 2 largest maternities in Botswana from 2009-2011 when Botswana National Guidelines recommended zidovudine (ZDV) from 28 weeks gestational age (GA) for CD4 ≥350 and ART for CD4 <350, and again in 2013-2014 after implementation of TDF/FTC/EFV for prevention of mother-to-child HIV transmission regardless of CD4 or GA. We compared the use of TDF/FTC/EFV in pregnancy with other 3-drug ART regimens, and with initiation of ZDV, among women with similar CD4 cell counts. Outcomes included small for gestational age (SGA), preterm delivery (PTD) (<37 weeks GA), and stillbirths (SB).

RESULTS

Among 9445 HIV-infected women delivering during the study period, 170 were on TDF/FTC/EFV at conception and 1468 initiated TDF/FTC/EFV during pregnancy. Adverse birth outcomes were high overall (3% SB, 21% PTD, and 18% SGA) and among women receiving TDF/FTC/EFV (3% SB, 22% PTD, and 12% SGA). There was no difference in PTD or SB among women initiating TDF/FTC/EFV compared with ZDV or other 3-drug ART, but initiating TDF/FTC/EFV was associated with fewer SGA infants than other 3-drug ART (adjusted odds ratio: 0.4, 95% confidence interval: 0.2 to 0.7).

CONCLUSIONS

Adverse birth outcomes remain high among HIV-infected women. TDF/FTC/EFV was at least as safe as other ART and associated with fewer SGA infants when initiated during pregnancy. Larger studies are needed to evaluate birth outcomes and congenital abnormalities among women on TDF/FTC/EFV at conception.

Comparative cost-effectiveness of Option B+ for prevention of mother-to-child transmission of HIV in Malawi

OBJECTIVE

To estimate the cost-effectiveness of prevention of mother-to-child transmission (MTCT) of HIV with lifelong antiretroviral therapy (ART) for pregnant and breastfeeding women ('Option B+') compared with ART during pregnancy or breastfeeding only unless clinically indicated ('Option B').

DESIGN

Mathematical modelling study of first and second pregnancy, informed by data from the Malawi Option B+ programme.

METHODS

Individual-based simulation model. We simulated cohorts of 10 000 women and their infants during two subsequent pregnancies, including the breastfeeding period, with either Option B+ or B. We parameterized the model with data from the literature and by analysing programmatic data. We compared total costs of antenatal and postnatal care, and lifetime costs and disability-adjusted life-years of the infected infants between Option B+ and Option B.

RESULTS

During the first pregnancy, 15% of the infants born to HIV-infected mothers acquired the infection. With Option B+, 39% of the women were on ART at the beginning of the second pregnancy, compared with 18% with Option B. For second pregnancies, the rates MTCT were 11.3% with Option B+ and 12.3% with Option B. The incremental cost-effectiveness ratio comparing the two options ranged between about US$ 500 and US$ 1300 per DALY averted.

CONCLUSION

Option B+ prevents more vertical transmissions of HIV than Option B, mainly because more women are already on ART at the beginning of the next pregnancy. Option B+ is a cost-effective strategy for PMTCT if the total future costs and lost lifetime of the infected infants are taken into account.

Perspectives on safer conception practices and preconception counseling among women living with HIV

Pregnancies are frequently unplanned, and higher rates of unplanned pregnancies occur among HIV-infected women. Reviewers examined reproductive decision making, conception practices, and patient-provider communication among women living with HIV. Qualitative interviews were conducted with 19 HIV-infected sexually active women aged 18-45 in southern Florida, USA. Using thematic analysis, we found decisions to conceive were influenced by women and partners; knowledge and use of safer conception practices were low. Discussion and support from partners, family, and providers was limited and diminished by stigma and nondisclosure. Preconception counseling discussions in HIV care should be comprehensive and initiated frequently by all health care providers.

Maraviroc: a review of its use in HIV infection and beyond

The human immunodeficiency virus-1 (HIV-1) enters target cells by binding its envelope glycoprotein gp120 to the CD4 receptor and/or coreceptors such as C-C chemokine receptor type 5 (CCR5; R5) and C-X-C chemokine receptor type 4 (CXCR4; X4), and R5-tropic viruses predominate during the early stages of infection. CCR5 antagonists bind to CCR5 to prevent viral entry. Maraviroc (MVC) is the only CCR5 antagonist currently approved by the United States Food and Drug Administration, the European Commission, Health Canada, and several other countries for the treatment of patients infected with R5-tropic HIV-1. MVC has been shown to be effective at inhibiting HIV-1 entry into cells and is well tolerated. With expanding MVC use by HIV-1-infected humans, different clinical outcomes post-approval have been observed with MVC monotherapy or combination therapy with other antiretroviral drugs, with MVC use in humans infected with dual-R5- and X4-tropic HIV-1, infected with different HIV-1 genotype or infected with HIV-2. This review discuss the role of CCR5 in HIV-1 infection, the development of the CCR5 antagonist MVC, its pharmacokinetics, pharmacodynamics, drug–drug interactions, and the implications of these interactions on treatment outcomes, including viral mutations and drug resistance, and the mechanisms associated with the development of resistance to MVC. This review also discusses available studies investigating the use of MVC in the treatment of other diseases such as cancer, graft-versus-host disease, and inflammatory diseases.

Implementation and Operational Research: Uptake of Services and Behaviors in the Prevention of Mother-to-Child HIV Transmission Cascade in Zimbabwe

OBJECTIVE

To examine the uptake of services and behaviors in the prevention of mother-to-child HIV transmission (PMTCT) cascade in Zimbabwe and to determine factors associated with MTCT and maternal antiretroviral therapy (ART) or antiretroviral (ARV) prophylaxis.

DESIGN

Analysis of cross-sectional data from mother-infant pairs.

METHODS

We analyzed baseline data collected in 2012 as part of the impact evaluation of Zimbabwe's Accelerated National PMTCT Program. Using multistage cluster sampling, eligible mother-infant pairs were randomly sampled from the catchment areas of 157 facilities in 5 provinces, tested for HIV infection, and interviewed about PMTCT service utilization.

RESULTS

Of 8800 women, 94% attended ≥ 1 antenatal care visit, 92% knew their HIV serostatus during pregnancy, 77% delivered in a health facility, and 92% attended the 6-8 week postnatal visit. Among 1075 (12%) HIV-infected women, 59% reported ART/ARV prophylaxis and 63% of their HIV-exposed infants received ARV prophylaxis. Among HIV-exposed infants, maternal receipt of ART/ARV prophylaxis was protective against MTCT [adjusted prevalence ratio (PR(a)): 0.41, 95% confidence interval (CI): 0.23 to 0.74]. Factors associated with receipt of maternal ART/ARV prophylaxis included ≥ 4 antenatal care visits (PR(a): 1.18, 95% CI: 1.01 to 1.38), institutional delivery (PR(a): 1.31, 95% CI: 1.13 to 1.52), and disclosure of serostatus (PRa: 1.30, 95% CI: 1.12 to 1.49).

CONCLUSIONS

These data from women in the community indicate gaps in the PMTCT cascade before the accelerated program, which may have been missed by examination of health facility data alone. These gaps were especially noteworthy for services targeted specifically to HIV-infected women and their infants, such as maternal and infant ART/ARV prophylaxis.

Evaluating the Impact of Zimbabwe's Prevention of Mother-to-Child HIV Transmission Program: Population-Level Estimates of HIV-Free Infant Survival Pre-Option A

Objective

We estimated HIV-free infant survival and mother-to-child HIV transmission (MTCT) rates in Zimbabwe, some of the first community-based estimates from a UNAIDS priority country.

Methods

In 2012 we surveyed mother-infant pairs residing in the catchment areas of 157 health facilities randomly selected from 5 of 10 provinces in Zimbabwe. Enrolled infants were born 9–18 months before the survey. We collected questionnaires, blood samples for HIV testing, and verbal autopsies for deceased mothers/infants. Estimates were assessed among i) all HIV-exposed infants, as part of an impact evaluation of Option A of the 2010 WHO guidelines (rolled out in Zimbabwe in 2011), and ii) the subgroup of infants unexposed to Option A. We compared province-level MTCT rates measured among women in the community with MTCT rates measured using program monitoring data from facilities serving those communities.

Findings

Among 8568 women with known HIV serostatus, 1107 (12.9%) were HIV-infected. Among all HIV-exposed infants, HIV-free infant survival was 90.9% (95% confidence interval (CI): 88.7–92.7) and MTCT was 8.8% (95% CI: 6.9–11.1). Sixty-six percent of HIV-exposed infants were still breastfeeding. Among the 762 infants born before Option A was implemented, 90.5% (95% CI: 88.1–92.5) were alive and HIV-uninfected at 9–18 months of age, and 9.1% (95%CI: 7.1–11.7) were HIV-infected. In four provinces, the community-based MTCT rate was higher than the facility-based MTCT rate. In Harare, the community and facility-based rates were 6.0% and 9.1%, respectively.

Conclusion

By 2012 Zimbabwe had made substantial progress towards the elimination of MTCT. Our HIV-free infant survival and MTCT estimates capture HIV transmissions during pregnancy, delivery and breastfeeding regardless of whether or not mothers accessed health services. These estimates also provide a baseline against which to measure the impact of Option A guidelines (and subsequently Option B+).

Eliminating mother-to-child transmission of the human immunodeficiency virus in sub-Saharan Africa: The journey so far and what remains to be done

This review was carried out to provide a comprehensive overview of efforts toward elimination of mother-to-child transmission (MTCT) of human immunodeficiency virus (HIV) with respect to progress, challenges, and recommendations in 21 sub-Saharan African priority countries. We reviewed literature published from 2011 to April 2015 using 3 databases; PubMed, Scopus, and Web of Science, as well as the 2014 Global Plan Progress Report. A total of 39 studies were included. Between 2009 and 2013, there was a 43% reduction in new HIV infections, the final MTCT rate was reduced from 28% to 18%, and antiretroviral therapy (ART) coverage increased from 11% to 24%. Challenges included poor adherence to antiretroviral therapy, poor linkage between mother-child pairs and post-natal healthcare services low early infant diagnosis coverage, low pediatric ART coverage, and high unmet needs for contraceptive services. Future recommendations include identification of key barriers, health system strengthening, strengthening community involvement, and international collaboration. There has been significant progress toward eliminating MTCT of HIV, but more effort is still needed.

Efficacy of WHO recommendation for continued breastfeeding and maternal cART for prevention of perinatal and postnatal HIV transmission in Zambia

Introduction

To prevent mother-to-child transmission (MTCT) of HIV in developing countries, new World Health Organization (WHO) guidelines recommend maternal combination antiretroviral therapy (cART) during pregnancy, throughout breastfeeding for 1 year and then cessation of breastfeeding (COB). The efficacy of this approach during the first six months of exclusive breastfeeding has been demonstrated, but the efficacy of this approach beyond six months is not well documented.

Methods

A prospective observational cohort study of 279 HIV-positive mothers was started on zidovudine/3TC and lopinavir/ritonavir tablets between 14 and 30 weeks gestation and continued indefinitely thereafter. Women were encouraged to exclusively breastfeed for six months, complementary feed for the next six months and then cease breastfeeding between 12 and 13 months. Infants were followed for transmission to 18 months and for survival to 24 months. Text message reminders and stipends for food and transport were utilized to encourage adherence and follow-up.

Results

Total MTCT was 9 of 219 live born infants (4.1%; confidence interval (CI) 2.2–7.6%). All breastfeeding transmissions that could be timed (5/5) occurred after six months of age. All mothers who transmitted after six months had a six-month plasma viral load >1,000 copies/ml (p<0.001). Poor adherence to cART as noted by missed dispensary visits was associated with transmission (p=0.04). Infant mortality was lower after six months of age than during the first six months of life (p=0.02). The cumulative rate of infant HIV infection or death at 18 months was 29/226 (12.8% 95 CI: 7.5–20.8%).

Conclusions

Maternal cART may limit MTCT of HIV to the UNAIDS target of <5% for eradication of paediatric HIV within the context of a clinical study, but poor adherence to cART and follow-up can limit the benefit. Continued breastfeeding can prevent the rise in infant mortality after six months seen in previous studies, which encouraged early COB.

Prenatal Transmission of Syphilis and Human Immunodeficiency Virus in Brazil: Achieving Regional Targets for Elimination

Background.  The Pan-American Health Organization has called for reducing (1) human immunodeficiency virus (HIV) mother-to-child transmission (MTCT) to ≤0.30 infections/1000 live births (LB), (2) HIV MTCT risk to ≤2.0%, and (3) congenital syphilis (CS) incidence to ≤0.50/1000 LB in the Americas by 2015. Methods.  Using published Brazilian data in a mathematical model, we simulated a cohort of pregnant women from antenatal care (ANC) through birth. We investigated 2 scenarios: "current access" (89.1% receive one ANC syphilis test and 41.1% receive 2; 81.7% receive one ANC HIV test and 18.9% receive birth testing; if diagnosed, 81.0% are treated for syphilis and 87.5% are treated for HIV) and "ideal access" (95% of women undergo 2 HIV and syphilis screenings; 95% receive appropriate treatment). We conducted univariate and multivariate sensitivity analyses on key inputs. Results.  With current access, we projected 2.95 CS cases/1000 LB, 0.29 HIV infections/1000 LB, 7.1% HIV MTCT risk, and 11.11 intrauterine fetal demises (IUFD)/1000 pregnancies, with significant regional variation. With ideal access, we projected improved outcomes: 1.00 CS cases/1000 LB, 0.10 HIV infections/1000 LB, HIV MTCT risk of 2.4%, and 10.65 IUFD/1000 pregnancies. Increased testing drove the greatest improvements. Even with ideal access, only HIV infections/1000 LB met elimination goals. Achieving all targets required testing and treatment >95% and reductions in prevalence and incidence of HIV and syphilis. Conclusions.  Increasing access to care and HIV and syphilis antenatal testing will substantially reduce HIV and syphilis MTCT in Brazil. In addition, regionally tailored interventions reducing syphilis incidence and prevalence and supporting HIV treatment adherence are necessary to completely meet elimination goals.

Point-of-care CD4 testing to inform selection of antiretroviral medications in south african antenatal clinics: a cost-effectiveness analysis

BACKGROUND

Many prevention of mother-to-child HIV transmission (PMTCT) programs currently prioritize antiretroviral therapy (ART) for women with advanced HIV. Point-of-care (POC) CD4 assays may expedite the selection of three-drug ART instead of zidovudine, but are costlier than traditional laboratory assays.

METHODS

We used validated models of HIV infection to simulate pregnant, HIV-infected women (mean age 26 years, gestational age 26 weeks) in a general antenatal clinic in South Africa, and their infants. We examined two strategies for CD4 testing after HIV diagnosis: laboratory (test rate: 96%, result-return rate: 87%, cost: $14) and POC (test rate: 99%, result-return rate: 95%, cost: $26). We modeled South African PMTCT guidelines during the study period (WHO "Option A"): antenatal zidovudine (CD4 ≤350/μL) or ART (CD4>350/μL). Outcomes included MTCT risk at weaning (age 6 months), maternal and pediatric life expectancy (LE), maternal and pediatric lifetime healthcare costs (2013 USD), and cost-effectiveness ($/life-year saved).

RESULTS

In the base case, laboratory led to projected MTCT risks of 5.7%, undiscounted pediatric LE of 53.2 years, and undiscounted PMTCT plus pediatric lifetime costs of $1,070/infant. POC led to lower modeled MTCT risk (5.3%), greater pediatric LE (53.4 years) and lower PMTCT plus pediatric lifetime costs ($1,040/infant). Maternal outcomes following laboratory were similar to POC (LE: 21.2 years; lifetime costs: $23,860/person). Compared to laboratory, POC improved clinical outcomes and reduced healthcare costs.

CONCLUSIONS

In antenatal clinics implementing Option A, the higher initial cost of a one-time POC CD4 assay will be offset by cost-savings from prevention of pediatric HIV infection.

Viral infections during pregnancy

Viral infections during pregnancy have long been considered benign conditions with a few notable exceptions, such as herpes virus. The recent Ebola outbreak and other viral epidemics and pandemics show how pregnant women suffer worse outcomes (such as preterm labor and adverse fetal outcomes) than the general population and non-pregnant women. New knowledge about the ways the maternal-fetal interface and placenta interact with the maternal immune system may explain these findings. Once thought to be 'immunosuppressed', the pregnant woman actually undergoes an immunological transformation, where the immune system is necessary to promote and support the pregnancy and growing fetus. When this protection is breached, as in a viral infection, this security is weakened and infection with other microorganisms can then propagate and lead to outcomes, such as preterm labor. In this manuscript, we review the major viral infections relevant to pregnancy and offer potential mechanisms for the associated adverse pregnancy outcomes.

Fertility desires and unmet need for family planning among HIV infected individuals in two HIV clinics with differing models of family planning service delivery

BACKGROUND

Eliminating family planning (FP) unmet need among HIV-infected individuals (PLHIV) is critical to elimination of mother-to-child HIV transmission. We assessed FP unmet need among PLHIV attending two clinics with differing models of FP services. Nsambya Home Care provided only FP information while Mulago HIV clinic provided information and contraceptives onsite.

METHODS

In a cross-sectional study conducted between February-June 2011, we documented pregnancies, fertility desires, and contraceptive use among 797 HIV-infected men and women (408 in Mulago and 389 in Nsambya). FP unmet need was calculated among women who were married, unmarried but had sex within the past month, did not desire the last or future pregnancy at all or wished to postpone for ≥ two years and were not using contraceptives. Multivariable analyses for correlates of FP unmet need were computed for each clinic.

RESULTS

Overall, 40% (315) had been pregnant since HIV diagnosis; 58% desired the pregnancies. Of those who were not pregnant, 49% (366) did not desire more children at all; 15.7% wanted children then and 35.3% later. The unmet need for FP in Nsambya (45.1%) was significantly higher than that in Mulago at 30.9% (p = 0.008). Age 40+ compared to 18-29 years (OR = 6.05; 95% CI: 1.69, 21.62 in Mulago and OR = 0.21; 95% CI: 0.05, 0.90 in Nsambya), other Christian denominations (Pentecostal and Seventh Day Adventists) compared to Catholics (OR = 7.18; 95% CI: 2.14, 24.13 in Mulago and OR = 0.23; 95% CI: 0.06, 0.80 in Nsambya), and monthly expenditure > USD 200 compared to < USD40 in Nsambya (OR = 0.17; 95% CI: 0.03, 0.90) were associated with FP unmet need.

CONCLUSIONS

More than half of the pregnancies in this population were desired. Unmet need for FP was very high at both clinics and especially at the clinic which did not have contraceptives onsite. Lower income and younger women were most affected by the lack of contraceptives onsite. Comprehensive and aggressive FP programs are required for fertility support and elimination of FP unmet need among PLHIV, even with integration of FP information and supplies into HIV clinics.

First population-level effectiveness evaluation of a national programme to prevent HIV transmission from mother to child, South Africa

Background

There is a paucity of data on the national population-level effectiveness of preventing mother-to-child transmission (PMTCT) programmes in high-HIV-prevalence, resource-limited settings. We assessed national PMTCT impact in South Africa (SA), 2010.

Methods

A facility-based survey was conducted using a stratified multistage, cluster sampling design. A nationally representative sample of 10 178 infants aged 4–8 weeks was recruited from 565 clinics. Data collection included caregiver interviews, record reviews and infant dried blood spots to identify HIV-exposed infants (HEI) and HIV-infected infants. During analysis, self-reported antiretroviral (ARV) use was categorised: 1a: triple ARV treatment; 1b: azidothymidine >10 weeks; 2a: azidothymidine ≤10 weeks; 2b: incomplete ARV prophylaxis; 3a: no antenatal ARV and 3b: missing ARV information. Findings were adjusted for non-response, survey design and weighted for live-birth distributions.

Results

Nationally, 32% of live infants were HEI; early mother-to-child transmission (MTCT) was 3.5% (95% CI 2.9% to 4.1%). In total 29.4% HEI were born to mothers on triple ARV treatment (category 1a) 55.6% on prophylaxis (1b, 2a, 2b), 9.5% received no antenatal ARV (3a) and 5.5% had missing ARV information (3b). Controlling for other factors groups, 1b and 2a had similar MTCT to 1a (Ref; adjusted OR (AOR) for 1b, 0.98, 0.52 to 1.83; and 2a, 1.31, 0.69 to 2.48). MTCT was higher in group 2b (AOR 3.68, 1.69 to 7.97). Within group 3a, early MTCT was highest among breastfeeding mothers 11.50% (4.67% to 18.33%) for exclusive breast feeding, 11.90% (7.45% to 16.35%) for mixed breast feeding, and 3.45% (0.53% to 6.35%) for no breast feeding). Antiretroviral therapy or >10 weeks prophylaxis negated this difference (MTCT 3.94%, 1.98% to 5.90%; 2.07%, 0.55% to 3.60% and 2.11%, 1.28% to 2.95%, respectively).

Conclusions

SA, a high-HIV-prevalence middle income country achieved <5% MTCT by 4–8 weeks post partum. The long-term impact on PMTCT on HIV-free survival needs urgent assessment.

Individualizing the WHO HIV and infant feeding guidelines: optimal breastfeeding duration to maximize infant HIV-free survival

OBJECTIVES

To determine how infant feeding recommendations can maximize HIV-free survival (HFS) among HIV-exposed, uninfected African infants, balancing risks of breast milk-associated HIV infection with setting-specific risks of illness and death associated with replacement feeding.

DESIGN

Validated mathematical model of HIV-exposed, uninfected infants, with published data from Africa.

METHODS

We projected 24-month HFS using combinations of: maternal CD4, antiretroviral drug availability, and relative risk of mortality among replacement-fed compared to breastfed infants ('RR-RF', range 1.0-6.0). For each combination, we identified the 'optimal' breastfeeding duration (0-24 months) maximizing HFS. We compared HFS under an 'individualized' approach, based on the above parameters, to the WHO 'public health approach' (12 months breastfeeding for all HIV-infected women).

RESULTS

Projected HFS was 65-93%. When the value of RR-RF is 1.0, replacement feeding from birth maximized HFS. At a commonly reported RR-RF value (2.0), optimal breastfeeding duration was 3-12 months, depending on maternal CD4 and antiretroviral drug availability. As the value of RR-RF increased, optimal breastfeeding duration increased. Compared to the public health approach, an individualized approach improved absolute HFS by less than 1% if RR-RF value was 2.0-4.0, by 3% if RR-RF value was 1.0 or 6.0, and by greater amounts if access to antiretroviral drugs was limited.

CONCLUSION

Tailoring breastfeeding duration to maternal CD4, antiretroviral drug availability, and local replacement feeding safety can optimize HFS among HIV-exposed infants. An individualized approach leads to moderate gains in HFS, but only when mortality risks from replacement feeding are very low or very high, or antiretroviral drug availability is limited. The WHO public health approach is beneficial in most resource-limited settings.

Outcomes in a cohort of women who discontinued maternal triple-antiretroviral regimens initially used to prevent mother-to-child transmission during pregnancy and breastfeeding--Kenya, 2003-2009

BACKGROUND

In 2012, the World Health Organization (WHO) amended their 2010 guidelines for women receiving limited duration, triple-antiretroviral drug regimens during pregnancy and breastfeeding for prevention of mother-to-child transmission of HIV (tARV-PMTCT) (Option B) to include the option to continue lifelong combination antiretroviral therapy (cART) (Option B+). We evaluated clinical and CD4 outcomes in women who had received antiretrovirals for prevention of mother-to-child transmission and then discontinued antiretrovirals 6-months postpartum.

METHODS AND FINDINGS

The Kisumu Breastfeeding Study, 2003-2009, was a prospective, non-randomized, open-label clinical trial of tARV-PMTCT in ARV-naïve, Kenyan women. Women received tARV-PMTCT from 34 weeks' gestation until 6-months postpartum when women were instructed to discontinue breastfeeding. Women with CD4 count (CD4) <250cells/mm3 or WHO stage III/IV prior to 6-months postpartum continued cART indefinitely. We estimated the change in CD4 after discontinuing tARV-PMTCT and the adjusted relative risk [aRR] for factors associated with declines in maternal CD4. We compared maternal and infant outcomes following weaning-when tARV-PMTCT discontinued-by maternal ARV status through 24-months postpartum. Compared with women who continued cART, discontinuing antiretrovirals was associated with infant HIV transmission and death (10.1% vs. 2.4%; P = 0.03). Among women who discontinued antiretrovirals, CD4<500 cells/mm3 at either initiation (21.8% vs. 1.5%; P = 0.002; aRR: 9.8; 95%-confidence interval [CI]: 2.4-40.6) or discontinuation (36.9% vs. 8.3%; P<0.0001; aRR: 4.4; 95%-CI: 1.9-5.0) were each associated with increased risk of women requiring cART for their own health within 6 months after discontinuing.

CONCLUSIONS

Considering the serious health risks to the woman's infant and the brief reprieve from cART gained by stopping, every country should evaluate the need for and feasibility to implement WHO Option B+ for PMTCT. Evaluating CD4 at antiretroviral initiation or 6-months postpartum can identify pregnant women who would most benefit from continuing cART in settings unable to implement WHO Option B+.

Factors associated with siman immunodeficiency virus transmission in a natural African nonhuman primate host in the wild

African green monkeys (AGMs) are naturally infected with simian immunodeficiency virus (SIV) at high prevalence levels and do not progress to AIDS. Sexual transmission is the main transmission route in AGM, while mother-to-infant transmission (MTIT) is negligible. We investigated SIV transmission in wild AGMs to assess whether or not high SIV prevalence is due to differences in mucosal permissivity to SIV (i.e., whether the genetic bottleneck of viral transmission reported in humans and macaques is also observed in AGMs in the wild). We tested 121 sabaeus AGMs (Chlorocebus sabaeus) from the Gambia and found that 53 were SIV infected (44%). By combining serology and viral load quantitation, we identified 4 acutely infected AGMs, in which we assessed the diversity of the quasispecies by single-genome amplification (SGA) and documented that a single virus variant established the infections. We thus show that natural SIV transmission in the wild is associated with a genetic bottleneck similar to that described for mucosal human immunodeficiency virus (HIV) transmission in humans. Flow cytometry assessment of the immune cell populations did not identify major differences between infected and uninfected AGM. The expression of the SIV coreceptor CCR5 on CD4+ T cells dramatically increased in adults, being higher in infected than in uninfected infant and juvenile AGMs. Thus, the limited SIV MTIT in natural hosts appears to be due to low target cell availability in newborns and infants, which supports HIV MTIT prevention strategies aimed at limiting the target cells at mucosal sites. Combined, (i) the extremely high prevalence in sexually active AGMs, (ii) the very efficient SIV transmission in the wild, and (iii) the existence of a fraction of multiparous females that remain uninfected in spite of massive exposure to SIV identify wild AGMs as an acceptable model of exposed, uninfected individuals.

IMPORTANCE

We report an extensive analysis of the natural history of SIVagm infection in its sabaeus monkey host, the African green monkey species endemic to West Africa. Virtually no study has investigated the natural history of SIV infection in the wild. The novelty of our approach is that we report for the first time that SIV infection has no discernible impact on the major immune cell populations in natural hosts, thus confirming the nonpathogenic nature of SIV infection in the wild. We also focused on the correlates of SIV transmission, and we report, also for the first time, that SIV transmission in the wild is characterized by a major genetic bottleneck, similar to that described for HIV-1 transmission in humans. Finally, we report here that the restriction of target cell availability is a major correlate of the lack of SIV transmission to the offspring in natural hosts of SIVs.

Risks and benefits of lifelong antiretroviral treatment for pregnant and breastfeeding women: a review of the evidence for the Option B+ approach

PURPOSE OF REVIEW

Considerable debate has emerged on whether Option B+ (B+), initiation of lifelong antiretroviral therapy (ART) for all pregnant and breastfeeding women, is the best approach to achieving elimination of mother-to-child-transmission. However, direct evidence and experience with B+ is limited. We review the current evidence informing the proposed benefits and potential risks of the B+ approach, distinguishing individual health concerns for mother and child from program delivery and public health issues.

RECENT FINDINGS

For mothers and infants, B+ may offer significant benefits for transmission prevention and maternal health. However, several studies raise concerns about the safety of ART exposure to fetuses and infants, as well as adherence challenges for pregnant and breastfeeding mothers. For program delivery and public health, B+ presents distinct advantages in terms of transmission prevention to uninfected partners and increased simplicity potentially improving program feasibility, access, uptake, and retention in care. Despite being more costly in the short-term, B+ will likely be cost effective over time.

SUMMARY

This review provides a detailed analysis of risks and benefits of B+. As national programs adopt this approach, it will be critical to carefully assess both short-term and long-term maternal and infant outcomes.

Prevention of mother-to-child HIV transmission within the continuum of maternal, newborn, and child health services

PURPOSE OF REVIEW

To reach virtual elimination of pediatric HIV, programs for the prevention of mother-to-child HIV transmission (PMTCT) must expand coverage and achieve long-term retention of mothers and infants. Although PMTCT have been traditionally aligned with maternal, newborn, and child health (MNCH) services, novel approaches are needed to address the increasing demands of evolving global PMTCT policies.

RECENT FINDINGS

PMTCT-MNCH integration has improved the uptake and timely initiation of antiretroviral therapy (ART) among treatment-eligible pregnant women in public health settings. Postpartum engagement of HIV-infected mothers and HIV-exposed infants has been insufficient, although alignment of visits to the childhood immunization schedule and establishment of integrated mother-infant clinics may increase retention. Evidence also suggests that the integration of maternal HIV testing into childhood immunization clinics can significantly increase the identification of at-risk HIV-exposed infants previously missed by traditional PMTCT models.

SUMMARY

Targeted service integration models can improve PMTCT uptake. However, as global PMTCT policy shifts to universal provision of maternal ART during pregnancy (i.e., Option B/B+), these findings must be reexamined in the context of increased service demand and systems burden. Intensive evaluation is needed to ensure quality clinical care is maintained both for PMTCT and for underpinning MNCH services.

Validation and calibration of a computer simulation model of pediatric HIV infection

Background

Computer simulation models can project long-term patient outcomes and inform health policy. We internally validated and then calibrated a model of HIV disease in children before initiation of antiretroviral therapy to provide a framework against which to compare the impact of pediatric HIV treatment strategies.

Methods

We developed a patient-level (Monte Carlo) model of HIV progression among untreated children <5 years of age, using the Cost-Effectiveness of Preventing AIDS Complications model framework: the CEPAC-Pediatric model. We populated the model with data on opportunistic infection and mortality risks from the International Epidemiologic Database to Evaluate AIDS (IeDEA), with mean CD4% at birth (42%) and mean CD4% decline (1.4%/month) from the Women and Infants’ Transmission Study (WITS). We internally validated the model by varying WITS-derived CD4% data, comparing the corresponding model-generated survival curves to empirical survival curves from IeDEA, and identifying best-fitting parameter sets as those with a root-mean square error (RMSE) <0.01. We then calibrated the model to other African settings by systematically varying immunologic and HIV mortality-related input parameters. Model-generated survival curves for children aged 0-60 months were compared, again using RMSE, to UNAIDS data from >1,300 untreated, HIV-infected African children.

Results

In internal validation analyses, model-generated survival curves fit IeDEA data well; modeled and observed survival at 16 months of age were 91.2% and 91.1%, respectively. RMSE varied widely with variations in CD4% parameters; the best fitting parameter set (RMSE = 0.00423) resulted when CD4% was 45% at birth and declined by 6%/month (ages 0-3 months) and 0.3%/month (ages >3 months). In calibration analyses, increases in IeDEA-derived mortality risks were necessary to fit UNAIDS survival data.

Conclusions

The CEPAC-Pediatric model performed well in internal validation analyses. Increases in modeled mortality risks required to match UNAIDS data highlight the importance of pre-enrollment mortality in many pediatric cohort studies.

Antiretroviral drug regimens to prevent mother-to-child transmission of HIV: a review of scientific, program, and policy advances for sub-Saharan Africa

Considerable advances have been made in the effort to prevent mother-to-child HIV transmission (PMTCT) in sub-Saharan Africa. Clinical trials have demonstrated the efficacy of antiretroviral regimens to interrupt HIV transmission through the antenatal, intrapartum, and postnatal periods. Scientific discoveries have been rapidly translated into health policy, bolstered by substantial investment in health infrastructure capable of delivering increasingly complex services. A new scientific agenda is also emerging, one that is focused on the challenges of effective and sustainable program implementation. Finally, global campaigns to "virtually eliminate" pediatric HIV and dramatically reduce HIV-related maternal mortality have mobilized new resources and renewed political will. Each of these developments marks a major step in regional PMTCT efforts; their convergence signals a time of rapid progress in the field, characterized by an increased interdependency between clinical research, program implementation, and policy. In this review, we take stock of recent advances across each of these areas, highlighting the challenges--and opportunities--of improving health services for HIV-infected mothers and their children across the region.

Improving utilization of and retention in PMTCT services: can behavioral economics help?

BACKGROUND

The most recent strategic call to action of the World Health Organization sets the elimination of pediatric HIV as a goal. While recent efforts have focused on building infrastructure and ensuring access to high-quality treatment, we must now turn our focus to the behavior change needed to eliminate vertical transmission. We make the case for the application of concepts from the field of behavioral economics to prevention of mother-to-child transmission (PMTCT) programs to more effectively address demand-side issues of uptake and retention.

DISCUSSION

We introduce five concepts from the field of behavioral economics and discuss their application to PMTCT programs: 1) Mentor mothers who come from similar circumstances as PMTCT patients can serve as social references who provide temporally salient modeling of utilization of services and adherence to treatment. 2) Economic incentives, like cell phone minutes or food vouchers, that reward adherence to PMTCT protocols leverage present bias, the observation that people are generally biased toward immediate versus future awards. 3) Default bias, our preference for the default option, is already being used in many countries in the form of opt-out testing, and could be expanded to all PMTCT programs. 4) We are hardwired to avoid loss more than to pursue an equivalent gain. PMTCT programs can take advantage of loss aversion through the use of commitment contracts that incentivize mothers to return to the clinic in order to avoid both reputational and financial loss.

SUMMARY

Eliminating vertical transmission of HIV is an ambitious goal. To close the remaining gap, innovations are needed to address demand for PMTCT services. Behavioral economics offers a set of tools that can be engineered into PMTCT programs to increase uptake and improve retention with minimal investment.

What is needed to eliminate new pediatric HIV infections: the contribution of model-based analyses

PURPOSE OF REVIEW

Computer simulation models can identify key clinical, operational, and economic interventions that will be needed to achieve the elimination of new pediatric HIV infections. In this review, we summarize recent findings from model-based analyses of strategies for prevention of mother-to-child HIV transmission (MTCT).

RECENT FINDINGS

In order to achieve elimination of MTCT (eMTCT), model-based studies suggest that scale-up of services will be needed in several domains: uptake of services and retention in care (the PMTCT 'cascade'), interventions to prevent HIV infections in women and reduce unintended pregnancies (the 'four-pronged approach'), efforts to support medication adherence through long periods of pregnancy and breastfeeding, and strategies to make breastfeeding safer and/or shorter. Models also project the economic resources that will be needed to achieve these goals in the most efficient ways to allocate limited resources for eMTCT. Results suggest that currently recommended PMTCT regimens (WHO Option A, Option B, and Option B+) will be cost-effective in most settings.

SUMMARY

Model-based results can guide future implementation science, by highlighting areas in which additional data are needed to make informed decisions and by outlining critical interventions that will be necessary in order to eliminate new pediatric HIV infections.

Feasibility and safety of ALVAC-HIV vCP1521 vaccine in HIV-exposed infants in Uganda: results from the first HIV vaccine trial in infants in Africa

BACKGROUND

The development of a safe and effective vaccine against HIV type 1 for the prevention of mother-to-child transmission of HIV would significantly advance the goal of eliminating HIV infection in children. Safety and feasibility results from phase 1, randomized, double-blind, placebo-controlled trial of ALVAC-HIV vCP1521 in infants born to HIV type 1-infected women in Uganda are reported.

METHODS

HIV-exposed infants were enrolled at birth and randomized (4:1) to receive vaccine or saline placebo intramuscular injections at birth, 4, 8, and 12 weeks of age. Vaccine reactogenicity was assessed at vaccination and days 1 and 2 postvaccination. Infants were followed until 24 months of age. HIV infection status was determined by HIV DNA polymerase chain reaction.

RESULTS

From October 2006 to May 2007, 60 infants (48 vaccine and 12 placebo) were enrolled with 98% retention at 24 months. One infant was withdrawn, but there were no missed visits or vaccinations among the 59 infants retained. Immune responses elicited by diphtheria, polio, hepatitis B, haemophilus influenzae type B, and measles vaccination were similar in the 2 arms. The vaccine was well tolerated with no severe or life-threatening reactogenicity events. Adverse events were equally distributed across both study arms. Four infants were diagnosed as HIV infected [3 at birth (2 vaccine and 1 placebo) and 1 in vaccine arm at 2 weeks of age].

CONCLUSION

The ALVAC-HIV vCP1521 vaccination was feasible and safe in infants born to HIV-infected women in Uganda. The conduct of high-quality infant HIV vaccine trials is achievable in Africa.

Comparative effectiveness of congregation- versus clinic-based approach to prevention of mother-to-child HIV transmission: study protocol for a cluster randomized controlled trial

Background

A total of 22 priority countries have been identified by the WHO that account for 90% of pregnant women living with HIV. Nigeria is one of only 4 countries among the 22 with an HIV testing rate for pregnant women of less than 20%. Currently, most pregnant women must access a healthcare facility (HF) to be screened and receive available prevention of mother-to-child HIV transmission (PMTCT) interventions. Finding new approaches to increase HIV testing among pregnant women is necessary to realize the WHO/ President's Emergency Plan for AIDS Relief (PEPFAR) goal of eliminating new pediatric infections by 2015.

Methods

This cluster randomized trial tests the comparative effectiveness of a congregation-based Healthy Beginning Initiative (HBI) versus a clinic-based approach on the rates of HIV testing and PMTCT completion among a cohort of church attending pregnant women. Recruitment occurs at the level of the churches and participants (in that order), while randomization occurs only at the church level. The trial is unblinded, and the churches are informed of their randomization group. Eligible participants, pregnant women attending study churches, are recruited during prayer sessions. HBI is delivered by trained community health nurses and church-based health advisors and provides free, integrated on-site laboratory tests (HIV plus hemoglobin, malaria, hepatitis B, sickle cell gene, syphilis) during a church-organized ‘baby shower.’ The baby shower includes refreshments, gifts exchange, and an educational game show testing participants’ knowledge of healthy pregnancy habits in addition to HIV acquisition modes, and effective PMTCT interventions. Baby receptions provide a contact point for follow-up after delivery. This approach was designed to reduce barriers to screening including knowledge, access, cost and stigma. The primary aim is to evaluate the effect of HBI on the HIV testing rate among pregnant women. The secondary aims are to evaluate the effect of HBI on the rate of HIV testing among male partners of pregnant women and the rate of PMTCT completion among HIV-infected pregnant women.

Discussion

Results of this study will provide further understanding of the most effective strategies for increasing HIV testing among pregnant women in hard-to-reach communities.

Trial Registration

Clinicaltrials.gov, NCT01795261

Impact of expanded access to combination antiretroviral therapy in pregnancy: results from a cohort study in Ukraine

OBJECTIVE

To investigate the scale-up of antenatal combination antiretroviral therapy (cART) in Ukraine since this became part of the national policy for the prevention of mother-to-child transmission (PMTCT) of human immunodeficiency virus (HIV).

METHODS

Data on 3535 HIV-positive pregnant women who were enrolled into the Ukraine European Collaborative Study in 2008-2010 were analysed. Factors associated with receipt of zidovudine monotherapy (AZTm) - rather than cART - and rates of mother-to-child transmission (MTCT) of HIV were investigated.

FINDINGS

cART coverage increased significantly, from 22% of deliveries in 2008 to 61% of those in 2010. After adjusting for possible confounders, initiation of antenatal AZTm - rather than cART - was associated with cohabiting (versus being married; adjusted prevalence ratio, aPR: 1.09; 95% confidence interval, CI: 1.02-1.16), at least two previous live births (versus none; aPR: 1.22; 95% CI: 1.11-1.35) and a diagnosis of HIV infection during the first or second trimester (versus before pregnancy; aPR: 1.11; 95% CI: 1.03-1.20). The overall MTCT rate was 4.1% (95% CI: 3.4-4.9); 42% (49/116) of the transmissions were from the 8% (n = 238) of women without antenatal ART. Compared with AZTm, cART was associated with a 70% greater reduction in the risk of MTCT (adjusted odds ratio: 0.30; 95% CI: 0.16-0.56).

CONCLUSION

Between 2008 and 2010, access to antenatal cART improved substantially in Ukraine, but implementation of the World Health Organization's Option-B policy was slow. For MTCT to be eliminated in Ukraine, improvements in the retention of women in HIV care and further roll-out of Option B are urgently needed.

Cost-effectiveness of World Health Organization 2010 guidelines for prevention of mother-to-child HIV transmission in Zimbabwe

BACKGROUND

In 2010, the World Health Organization (WHO) released revised guidelines for prevention of mother-to-child human immunodeficiency virus (HIV) transmission (PMTCT). We projected clinical impacts, costs, and cost-effectiveness of WHO-recommended PMTCT strategies in Zimbabwe.

METHODS

We used Zimbabwean data in a validated computer model to simulate a cohort of pregnant, HIV-infected women (mean age, 24 years; mean CD4 count, 451 cells/µL; subsequent 18 months of breastfeeding). We simulated guideline-concordant care for 4 PMTCT regimens: single-dose nevirapine (sdNVP); WHO-recommended Option A, WHO-recommended Option B, and Option B+ (lifelong maternal 3-drug antiretroviral therapy regardless of CD4). Outcomes included maternal and infant life expectancy (LE) and lifetime healthcare costs (2008 US dollars [USD]). Incremental cost-effectiveness ratios (ICERs, in USD per year of life saved [YLS]) were calculated from combined (maternal + infant) discounted costs and LE.

RESULTS

Replacing sdNVP with Option A increased combined maternal and infant LE from 36.97 to 37.89 years and would reduce lifetime costs from $5760 to $5710 per mother-infant pair. Compared with Option A, Option B further improved LE (38.32 years), and saved money within 4 years after delivery ($5630 per mother-infant pair). Option B+ (LE, 39.04 years; lifetime cost, $6620 per mother-infant pair) improved maternal and infant health, with an ICER of $1370 per YLS compared with Option B.

CONCLUSIONS

Replacing sdNVP with Option A or Option B will improve maternal and infant outcomes and save money; Option B increases health benefits and decreases costs compared with Option A. Option B+ further improves maternal outcomes, with an ICER (compared with Option B) similar to many current HIV-related healthcare interventions.

Progress, challenges, and new opportunities for the prevention of mother-to-child transmission of HIV under the US President's Emergency Plan for AIDS Relief

In June 2011, the Joint United Nations Programme on HIV/AIDS, the US President's Emergency Plan for AIDS Relief (PEPFAR), and other collaborators outlined a transformative plan to virtually eliminate pediatric AIDS worldwide. The ambitious targets of this initiative included a 90% reduction in new pediatric HIV infections and a 50% reduction in HIV-related maternal mortality--all by 2015. PEPFAR has made an unprecedented commitment to the expansion and improvement of prevention of mother-to-child HIV transmission (PMTCT) services globally and is expected to play a critical role in reaching the virtual elimination target. To date, PEPFAR has been instrumental in the success of many national programs, including expanded coverage of PMTCT services, an enhanced continuum of care between PMTCT and HIV care and treatment, provision of more efficacious regimens for antiretroviral prophylaxis, design of innovative but simplified PMTCT approaches, and development of new strategies to evaluate program effectiveness. These accomplishments have been made through collaborative efforts with host governments, United Nations agencies, other donors (eg, the Global Fund for AIDS, Tuberculosis, and Malaria), nongovernmental organizations, and private sector partners. To successfully meet the ambitious global targets to prevent new infant HIV infections, PEPFAR must continue to leverage the existing PMTCT platform, while developing innovative approaches to rapidly expand quality HIV services. PEPFAR must also carefully integrate PMTCT into the broader combination prevention agenda for HIV, so that real progress can be made toward an "AIDS-free generation" worldwide.

Pediatric HIV/AIDS in sub-Saharan Africa: emerging issues and way forward

BACKGROUND

Sub-Saharan Africa has the largest burden of pediatric HIV in the world. Global target has been set for eradication of pediatric HIV by 2015 but there are still so many complex issues facing HIV infected and affected children in the sub-continent.

OBJECTIVE

To review the current and emerging challenges facing pediatric HIV care in sub-Saharan Africa; and proffer solutions that could help in tackling these challenges.

METHOD

A Medline literature search of recent publications was performed to identify articles on "pediatric HIV", "HIV and children", "HIV and infants", "HIV and adolescents" in sub-Saharan Africa.

RESULT

There are a number of challenges and emerging complex issues facing children infected and affected by HIV in sub-Saharan Africa. These include late presentation, limited access to pediatric HIV services, delayed diagnosis, infant feeding choices, malnutrition, limited and complex drug regimen, disclosure, treatment failure and reproductive health concerns. A holistic cost effective preventive, diagnostic and treatment strategies are required in order to eliminate pediatric HIV in SSA.

CONCLUSION

HIV infected children and their families in sub-Saharan Africa face myriad of complex medical and psychosocial issues. A holistic health promotional approach is being advocated as the required step for eradication of pediatric HIV in Africa.