Zachery Lewis, Dept. of Food Science and Technology and Foods for Health Institute, University of California, Davis, USA
Zachery T. Lewis1,2, The Baby-Associated Built Environment (BABE) Microbiome Project Team1, and David A. Mills1,2,3
1. Department of Food Science and Technology, University of California, Davis;
2. Foods for Health Institute, University of California, Davis;
3. Department of Viticulture and Enology, University of California Davis
Bifidobacteria are a major component of the gut microbiome of breast-fed infants, where they consume human milk oligosaccharides. Bifidobacterial colonization of the infant gastrointestinal tract is associated with several positive health outcomes. It is unknown how infants acquire bifidobacteria, though it has been hypothesized that these bacteria may be passed from mother to child or between infants, possibly via the surrounding human-built environment. This study investigates potential built environment-mediated transmission of bifidobacteria to infants. To determine if bifidobacteria were present in locations frequented by infants and mothers, swab samples were collected from surfaces with which they come into contact, including surfaces in lactation rooms, baby-changing tables, and daycare centers. In order to account for the possible influence of temperature, relative humidity, and room usage on bifidobacteria deposition and survival, custom sensors were installed in rooms to monitor these factors. To test the influence of temperature on extracorporeal bifidobacterial survival, a model species of bifidobacteria (Bifidobacterium longum subsp. infantis) was incubated aerobically under an array of temperatures and assayed for viabilit at regular time intervals. Bifidobacteria were found in areas frequented by breast-feeding mothers, suggesting that mothers are potential bifidobacterial vectors. Bifidobacteria survived longer at colder temperatures and were found to survive extracorporeally for up to two weeks. Usage tracking via in-room sign-in sheets confirmed the accuracy of the infrared beam-break approach to tracking room usage used here. Future experiments will investigate whether bifidobacteria may be transmitted between infants and how the microbiota of these surfaces differs between sites, environmental conditions, and over time.