“…Further, the mucosal contiguity of the upper and lower respiratory tract necessitates that pharyngeal microbiota not be overlooked as an important contributor to lower respiratory tract pathology. Readers are directed to recent reviews and monographs for more extensive discussions of sampling considerations in respiratory microbiome studies (14,55,56). Once suitable targets are identified (Barrier 1), a critical knowledge gap remains: we do not know how to optimally modulate respiratory microbiomes, using either available interventions (e.g., antibiotics) or with experimental modalities (e.g., inhaled probiotics).…”