Evaluating the Influence of an Improved Piped Water Network on Water Quality and Gut Microbiome Composition Among Children in Mozambique - PROJECT SUMMARY/ABSTRACT The gut microbiome plays a significant role in immune function, infection resistance, cognitive function, metabolism, and growth. The first year of life is a critical period for the development of a healthy and diverse gut microbiome. Enteropathogen infection and heavy metal exposures have also been associated with measurable changes in gut microbiome composition - a primary route of exposure being consumption of contaminated drinking water. While we know that gut microbiome composition is heavily influenced by early environmental exposures such as mode of delivery and diet, there are key gaps in our understanding of the impact of other environmental exposures, specifically drinking water, on the developing gut microbiome. I hypothesize that drinking water quality, and associated factors such as reliability and access, is associated with gut microbiome composition during the first year of life. Access to a safely managed water supply is critical for health and well- being. Interventions to improve drinking water access and quality often fall short of achieving measurable health gains, possibly because the intervention fails to effectively reduce contamination and sustainably increase access. Comprehensive, reliable estimates of exposure are necessary to understand why an intervention achieved – or failed to achieve - expected health gains, but reliable estimates of exposure are rarely used in practice. Specific Aim 1 in this proposal aims to address this gap by comprehensively evaluating whether or not a large-scale intervention (i.e., the provision of an improved piped water network) is effective in reducing microbial and toxicological contamination and increasing water access. Results from this aim will improve our understanding of the overall impact of a community-wide intervention on drinking water quality and access. Specific Aim 2 will assess whether a large-scale water intervention is associated with differences in child gut microbiome composition. This aim will fill knowledge gaps on the health effects of a large-scale water intervention in low-income settings, which are sorely needed to improve child health. Specific Aim 3 provides the first opportunity to assess whether drinking water quality, an important but overlooked environmental exposure in gut microbiome research, is associated with gut microbiome composition among children. Since harms to the gut influence health outcomes in addition to diarrhea, such as growth and metabolic function, investigating the influence of drinking water quality on gut microbiome composition allows us to assess the total effects of water quality on gut health. Results from this aim will provide insight into the relationship between water quality and the gut microbiome, which is critical for understanding both acute and chronic health outcomes associated with early perturbations to the gut.
