Mitigating Infectious Morbidity and Growth Deficits in HIV Exposed Uninfected infanTs With Human Milk Oligosaccharides

Primary Objective: * To evaluate the effects of synbiotics on infectious morbidity and growth while it is in place from 4 to 24 weeks of age. * To evaluate the effects of synbiotics on infectious morbidity and growth from 4 to 48 weeks of age. Secondary Objectives: * To evaluate the effects of synbiotics on growth from 4 to 72 weeks of age. * To evaluate the effects of synbiotics on infant neurodevelopment at 48 and 72 weeks of age. * To evaluate the effects of synbiotics on biological measurements while it is in place from 4 to 24 weeks of age. * To evaluate the effects of synbiotics on biological measurements from 4 to 48 weeks of age. * To evaluate the effects of synbiotics on gut microbiome and fecal short chain fatty acids from 4 to 72 weeks of age. * To investigate feasibility, acceptance, tolerability, and behavioral adherence with the intervention. * To investigate whether the synbiotics reduces infectious morbidity and improves growth in CHEU relative to CHUU. * To investigate whether infant gut microbiota composition, maturity and function, and markers of inflammation and HMOs at baseline and over time are associated with morbidity and poor growth in CHEU and CHUU.

Children who are HIV-exposed uninfected (CHEU), i.e., children born to mothers with HIV but who do not acquire HIV infection, have a higher risk of mortality, infectious morbidity, and growth deficits than children who are HIV-unexposed uninfected (CHUU), i.e., children whose mothers do not have HIV. Prior research has focused on breastfeeding and has pointed to changes in human milk oligosaccharides (HMOs) associated with maternal HIV infection that appear to influence the infant microbiome and thereby lead to these adverse outcomes. A randomized trial of an intervention which combines HMOs and probiotics in breastfed CHEU will be conducted in South Africa to evaluate whether this intervention has the potential to reduce excess infectious morbidity and growth faltering risks observed in CHEU. CHEU will be randomized 1:1 to either a) intervention (synbiotic: 2'-FL HMO + B. infantis probiotic) or b) placebo (Maltodextrin). The study intervention or placebo will be given from 4-24 weeks of age (total 20 weeks), followed by another 48 weeks of observation off study treatment. Both arms will be followed to 72 weeks of age for assessment of infant outcomes.