Mouthwashes against SARS-CoV-2 – Clinical pilot study proves reduction of the viral load

Introduction

ince the emergence of SARS-CoV-2 in Asia at the end of 2019, the global COVID-19 pandemic has persisted despite protective measures and vaccination campaigns and requires additional preventive measures. Until now, mouthwashes have been used mainly to improve oral health and reduce the number of microorganisms. The aim of this clinical observational study was to investigate whether mouthwashes can also reduce the viral load in throat swabs of SARS-CoV-2 positive patients, thus helping to reduce their infectiousness and slow the spread of this pandemic virus.

Question

Can the antiviral mouth and throat rinse lower the viral load of SARS-CoV-2 in the oropharynx and thus reduce the risk of droplet transmission of coronaviruses?

Material and methods

For this study, 34 COVID-19 patients treated in the hospital with initial positive SARS-CoV-2 tests (PCR test) were recruited. A throat swab (oropharynx) was taken from the patients before and after using the antiviral mouth and throat rinse. The viral load of the throat swabs was determined using RT-qPCR ("Reverse Transcriptase quantitative Real Time Polymerase Chain Reaction"). Additionally, new formulations were tested in vitro with respect to a possible anti-inflammatory impact, which could be an additional possibility for a positive effect of future mouthwashes.

Results

The clinical observational study showed that after use, the mouthwash reduced the viral load in the saliva of patients who were tested positive for SARS-CoV-2 by up to approx. 90%. This reduction of the viral load lasted up to 6 hours

The analysis of various experimental mouthwashes also showed that dexpanthenol and zinc reduce the expression of proinflammatory molecules, so already existing mouthwashes could be supplemented with dexpanthenol and zinc.

Fig.: Timeline of the viral load in the nasopharynx after using the mouth and throat rinse (adapted from Schürmann et al.).
Fig.: Timeline of the viral load in the nasopharynx after using the mouth and throat rinse (adapted from Schürmann et al.).

Conclusion

The antiviral mouth and throat rinse helps to reduce the infectiousness of COVID-19 patients and enhances protection against infections with SARS-CoV-2. 

The publication of the study can be found here.

Source:  Schürmann M. et al. Mouthrinses against SARS-CoV-2 – anti-inflammatory effectivity and a clinical pilot study. Eur Arch Otorhinolaryngol. 2021 May 22;1-9. doi: 10.1007/s00405-021-06873-8