SEPSIS Human Microbiome Study

Human-associated microbes are a key determinant of human health, development and disease. For instance, microbial communities in the human gut play a vital role in host metabolism and in the stimulation and development of the host innate immune system. Perturbations to these microbial assemblies, referred to as dysbiosis, are linked to negative health outcomes including allergies, obesity, undernutrition and early childhood sepsis. Most of what we know about the microbiome comes from high-income settings. This is because, low- and middle-income countries (LMICs) are currently underrepresented in global microbiome study. In addition, recent work highlights the influence of geography on the composition and stability of the gut microbiota. For example, Prevotella, prevalent in LMICs, is virtually absent in high-income countries. Even within LMICs, the relative abundance of Prevotella varies substantially. For instance, among Bangladeshi children the presence of Prevotella is far below that in children from Mali, Kenya and The Gambia. This study will describe the composition, diversity, stability, and metabolic activity of gut and body microorganisms in Bangladeshi mother-infant pairs and examine how each of these characteristics vary temporally and by body habitat, mode of delivery, exposure to antibiotics and maternal, infant and household characteristics. In addition, it will examine the human milk oligosaccharide (HMO) profile of breast milk collected from lactating women in Bangladesh and examine how HMO profile varies temporally, and by secretor status, maternal age, parity, diet, mode of delivery, season of milk collection, infant feeding pattern, and other maternal, infant and household characteristics. This will help us understand the relationship between mother and infant gut and body microbial communities over time and in the early postnatal period, gut microbiomes and microbial derived metabolites in mother-infant pairs and finally, HMO profiles and the composition of the infant gut microbiome.