The Impacts of the Occupants on the Bacterial Communities of Classrooms.

In modern societies, people spend most of their time in the built environment which harbors unique microbial assemblages with the potential to influence human health. However, how the occupants of buildings influence indoor microbial communities remains under-researched. Here, we investigated the diversities of the bacterial communities of a typical Chinese middle school to demonstrate the effects of occupant activities on bacterial communities inside classrooms. The results showed that samples taken from classrooms exhibited higher microbial diversity compared to samples collected from public areas such as gym and restaurant, suggesting the occupant activities could increase the diversities of the indoor microbial communities. Moreover, we also found that the duration of occupation strongly influence the presence/absence of phylogenetic lineages of the bacterial communities, the type of occupants, on the other hand, affect the relative abundances of bacterial taxa. In addition, samples taken from classrooms with longer occupation time exhibited a better fit to the Sloan Neutral Community Model for Prokaryotes, suggesting that room occupation influences the assembly process of microbial communities. In conclusion, our study demonstrates that the duration of occupation and the type of occupants influence the microbiome of the built environment.