Translational Aspects of the Human Respiratory Virome

Despite the dominant role of community-acquired respiratory viruses as etiological agents of disease, there has been little focus to date on the translation of rapidly developing diagnostic modalities, such as next-generation sequencing, techniques in the examination of lower respiratory tract samples. When applied, these techniques should inform strategies to both understand the nexus between health and disease states of the respiratory virome, and drive a paradigm shift in how the practicing pulmonologist views the conceptual framework of respiratory infections. The lower respiratory tract was once thought to be a sanctuary site from microbiological colonization owing to the efficacy of upper airway-protective mechanisms and the host mucosal barrier function of the lower airways, combined with both innate and adaptive immune responses. As a small number of recent studies confirm, this is a naive vision of the lung, the viral component of which parallels recent revelations from respiratory microbiome studies. Hence, it is now timely to revise our thinking regarding the constituents, diversity, and changing nature of the respiratory virome in health and disease. One area worthy of focus is the interface between community-acquired respiratory viruses and the respiratory virome to better understand the dynamics in acute infection, as well as the factors that may lead to viral persistence and chronic disease. Given recent advances in metagenomics, the tools are now at hand to accomplish these goals.