Dispersion characteristics of oral microbial communities in a built environment

Advances in next-generation sequencing (NGS) technologies since 2005 have revolutionized biological science. One particular application of NGS technologies is to elucidate microbiomes in built environments. We are currently conducting a series of studies on the elucidation and control of mass infection mechanisms based on dynamic measurement of environment microbiomes. The objective of this study is to clarify the dispersion characteristics of oral bacteria in the built environment. Bacterial communities from occupants’ hands and oral cavities, doorknobs, desk and keyboard surfaces, and air in laboratories were investigated in seven Japanese universities. The median relative abundances of Firmicutes, Proteobacteria, Actinobacteria, Bacteroidetes, and Fusobacteria were 41%, 31%, 12%, 7%, and 3%, respectively. Moreover, the main genera detected were Streptococcus (27.6%), Haemophilus (7.0%), Staphylococcus (5.6%), Neisseria (5.6%), Corynebacterium (4.7%), Rothia (3.2%), Prevotella (3.0%), Fusobacterium (2.6%), Veillonella (1.7%), Leptotrichia (1.7%), Enhydrobacter (1.7%), Lactobacillus (1.3%), Acinetobacter (1.3%), and Actinomyces (1.1%). The oral bacteria Actinomyces, Corynebacterium, Fusobacterium, Haemophilus, Leptotrichia, Neisseria, Prevotella, Rothia, and Streptococcus were observed in indoor air and on surfaces as well as in oral cavities. Furthermore, Prevotella melaninogenica and Rothia mucilaginosa were observed in all samples, including those from hands and oral cavities, doorknobs, desk and PC keyboard surfaces, and air in laboratories, in all seven universities.