The Role of Saliva and Mouthwashes in the Detection and Reduction of Oral Viral Load: A Scoping Review.

Background: The oral cavity is an entry site and a reservoir for viruses. Viral particles accumulate in saliva, which serves as a diagnostic fluid and vehicle for transmission (droplets and aerosols). Antiseptic mouthwashes were proposed as adjunctive measures to temporarily reduce oral viral load. Objectives: This scoping review aims to investigate the role of the oral cavity in viral infections, focusing on saliva and the use of antiseptic mouthwashes to reduce salivary viral load. Methods: Following the PRISMA-ScR guidelines, PubMed, EMBASE, and Web of Science were searched for human studies (2015-2025) investigating oral viral infections, saliva, or mouthwashes. Eligible studies were classified and analyzed for population, intervention, and outcomes. Results: Twenty-three studies met inclusion criteria (sixteen randomized controlled trials and seven systematic reviews). All included studies focused exclusively on SARS-CoV-2, as no clinical evidence on other oral viruses met the eligibility criteria. Saliva was consistently identified as a reliable, non-invasive specimen reflecting disease dynamics and transmission potential. Mouthwashes containing povidone-iodine, cetylpyridinium chloride, chlorhexidine, hydrogen peroxide or β-cyclodextrin-citrox produced measurable but short-lived reductions in salivary viral load. Heterogeneity and lack of standardized outcomes limited comparability. Conclusions: Antiseptic mouthwashes can provide a transient and complementary reduction in salivary viral load, particularly before aerosol-generating procedures; however, they should be regarded only as adjunctive measures and not as substitutes for standard infection-control protocols.