Mini review: Prevention of mother-child transmission of HIV: 25 years of continuous progress toward the eradication of pediatric AIDS?

Breastfeeding Outcomes and Associated Risks in HIV-Infected and HIV-Exposed Infants: A Systematic Review

Purpose: To critically appraise recent literature regarding breastfeeding outcomes and associated risks in HIV-infected (HI) and HIV-exposed (HE) infants, using the Preferred Reporting Items for Systematic review and Meta-Analysis Protocols (PRISMA-P) statement guidelines. Materials and Methods: Five electronic databases were systematically searched to obtain English publications from the last 10 years (2010-2020), pertaining to breastfeeding outcomes and associated risks of HI and HE infants and children. Gray literature sources were also included. Data were extracted according to various data items and were synthesized using thematic synthesis. Results: Of the initial 7,151 sources identified, 42 articles were eligible for final inclusion. The final selection included 19 cohort studies and 2 expert committee reports, classified as gray literature. The remaining 21 studies comprised case-control, cross-sectional, and randomized controlled trial studies. The following themes were identified: breastfeeding outcomes in HI and HE infants, risks for suboptimal breastfeeding, HI and HE infant growth and developmental outcomes, and barriers and facilitators to feeding decisions. Most studies highlighted HE infants' growth and developmental outcomes and did not directly interrogate breastfeeding outcomes. The most prevalent risks for suboptimal breastfeeding were maternal factors affecting decision making for breastfeeding. Conclusions: This systematic review adds to the evidence of breastfeeding in HIV-affected mother-infant dyads. Findings reiterated that exclusive breastfeeding has a positive outcome on growth and development of all infants irrespective of HIV status. The review highlighted a dearth of research on breastfeeding outcomes of HI and HE infants. Large-scale prospective comparative studies should profile breastfeeding and developmental outcomes of infants with HIV infection or exposure and antiretroviral treatment exposure to enable early identification and intervention for this vulnerable population in low-income settings.

Significance of the placental barrier in antenatal viral infections

The placenta provides a significant physical and physiological barrier to prevent fetal infection during pregnancy. Nevertheless, it is at times breached by pathogens and leads to vertical transmission of infection from mother to fetus. This review will focus specifically on the Zika flavivirus, the HIV retrovirus and the emerging SARS-CoV2 coronavirus, which have affected pregnant women and their offspring in recent epidemics. In particular, we will address how viral infections affect the immune response at the maternal-fetal interface and how the placental barrier is physically breached and discuss the consequences of infection on various aspects of placental function to support fetal growth and development. Improved understanding of how the placenta responds to viral infections will lay the foundation for developing therapeutics to these and emergent viruses, to minimise the harms of infection to the offspring.

HIV in pregnancy: Mother-to-child transmission, pharmacotherapy, and toxicity

An estimated 1.3 million pregnant women were living with HIV in 2018. HIV infection is associated with adverse pregnancy outcomes and all HIV-positive pregnant women, regardless of their clinical stage, should receive a combination of antiretroviral drugs to suppress maternal viral load and prevent vertical fetal infection. Although antiretroviral treatment in pregnant women has undoubtedly minimized mother-to-child transmission of HIV, several uncertainties remain. For example, while pregnancy is accompanied by changes in pharmacokinetic parameters, relevant data from clinical studies are lacking. Similarly, long-term adverse effects of exposure to antiretrovirals on fetuses have not been studied in detail. Here, we review current knowledge on HIV effects on the placenta and developing fetus, recommended antiretroviral regimens, and pharmacokinetic considerations with particular focus on placental transport. We also discuss recent advances in antiretroviral research and potential effects of antiretroviral treatment on placental/fetal development and programming.