Salivary microbiota (16S rRNA) of the oral cavity in chronically homeless adults and its association with extremophile environmental bacteria

Studies on the oral microbiota of chronically homeless adults (CHA) are scarce, despite the unique environmental and physiological stressors this population endures. Limited access to healthcare, poor nutrition, frequent substance use, and close contact with stray animals can significantly alter the oral microenvironment. In this study, we aimed to characterize the salivary microbiota of CHA and explore the presence of environmental extremophilic bacteria. We analyzed saliva samples from 60 chronically homeless men and 40 asymptomatic, never-homeless men living in Mexico City. DNA was extracted, and the V1-V3 regions of the 16S rRNA gene were sequenced.