Despite its prominence in early scientific records, the usefulness of saliva as a respiratory specimen has been de-emphasised over the past century. However, due to its low cost and reliance on specific supply chains and the non-invasive nature of its collection, its benefits over swab-based specimens are again becoming increasingly recognised. These benefits were highlighted over the course of the COVID-19 pandemic, where saliva emerged as a more practical, clinically non-inferior sample type for the detection of SARS-CoV-2 and saw numerous saliva-based diagnostic tests approved for clinical use. Looking forward, as saliva uniquely contains both respiratory secretions and immunological components, it has potentially wide applications, ranging from clinical diagnostics to post-vaccine disease burden and immunity surveillance. This Personal View seeks to summarise the existing evidence for the use of saliva in detecting respiratory pathogens, beyond SARS-CoV-2, as well as detailing methodological factors that can influence sample quality and thus, clinical utility.
Copyright © 2023 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY-NC-ND 4.0 license. Published by Elsevier Ltd.. All rights reserved.