Indoor Dust Microbiome and Resistome in Three Different Building Environments and Its Impact on the Human Nasopha-ryngeal Microbiome. Indoor dust microbiome and its impact on the human nasopharyngeal microbiome

Indoor dust particles represent a significant reservoir of microorganisms to which humans are daily exposed. By inhalation of these microorganisms, colonization of the respiratory tract and subsequent development of diseases may occur. In this study, we investigated a dust microbiome from 3 different building environments (households, hospitals, and offices) and com-pared it to the nasopharyngeal microbiome of occupants working or living in sampled buildings. Moreover, an analysis of antimicrobial resistance genes in the dust samples was performed. Obtained data revealed higher bacterial diversity in hospitals and offices than in households. The dust microbiome from hospitals was the most diverse, reflecting a possible effect of higher levels of human occupancy. Moreover, 242 different antimicrobial resistance genes were detected in the dust samples representing a possible risk to human health. An analysis of the nasopharyngeal microbiome revealed a significantly different bacterial composition in people working in the Neonatology Department compared to other study participants, and in all of those workers, we observed enrichment with new bacterial genera in their nasopharynx after spending 8 hours at work. These results suggest that a short-term exposure to the indoor microbiome can influence the human nasopharyngeal microbiome.