Effective in vitro inactivation of SARS-CoV-2 by commercially available mouthwashes

Infectious SARS-CoV-2 can be recovered from the oral cavities and saliva of COVID-19 patients with potential implications for disease transmission. Reducing viral load in patient saliva using antiviral mouthwashes may therefore have a role as a control measure in limiting virus spread, particularly in dental settings. Here, the efficacy of SARS-CoV-2 inactivation by seven commercially available mouthwashes with a range of active ingredients were evaluated in vitro. We demonstrate >= 4.1 to >= 5.5 log(10) reduction in SARS-CoV-2 titre following a 1 min treatment with commercially available mouthwashes containing 0.01-0.02 % stabilised hypochlorous acid or 0.58% povidone iodine, and non-specialist mouthwashes with both alcohol-based and alcohol-free formulations designed for home use. In contrast, products containing 1.5% hydrogen peroxide or 0.2% chlorhexidine gluconate were ineffective against SARS-CoV-2 in these tests. This study contributes to the growing body of evidence surrounding virucidal efficacy of mouthwashes/oral rinses against SARS-CoV-2, and has important applications in reducing risk associated with aerosol generating procedures in dentistry and potentially for infection control more widely.

Automated summary

This study evaluated the efficacy of seven commercially available mouthwashes in inactivating SARS-CoV-2, showing significant reductions in viral titres with specific mouthwash formulations. Mouthwashes containing stabilised hypochlorous acid, povidone iodine, and alcohol-based or alcohol-free formulations were effective, while those containing hydrogen peroxide or chlorhexidine gluconate were not effective. These findings have important implications for infection control in dental settings and beyond.