A Mouthwash with Cetylpyridinium Chloride Is Reducing Salivary SARS-CoV-2 Viral Load in +COVID-19.

Aim: The aim of this randomised, double-blind, placebo-controlled pilot clinical trial is to evaluate the capacity of a mouthwash to reduce SARS-CoV-2 viral load in the saliva of patients with COVID-19. Methods: Twenty-three symptomatic SARS-CoV-2-positive outpatients were selected and randomised into two groups and registered at NTC 04563689. Both groups rinsed and gargled for one minute with either distilled water (Placebo) or with 0.05% Cetylpyridinium chloride (CPC) plus 0.12% Chlorhexidine (CHX) mouthwash (PERIOAID Intensive CareÒ). Saliva samples were collected before the use of placebo or mouthwash and after 15 minutes and 1 and 2 hours of either of the above treatment. A saliva sample was also taken five days after regular use of placebo or mouthwash twice daily. The virus was detected by qRT-PCR. Results: A great heterogeneity in the viral load values was observed at baseline in both groups for nasopharyngeal and saliva samples. Most of the patients who used the mouthwash (8/12) had a significant decrease in baseline viral load after 15 min (greater than 99% reduction). This inhibitory effect was maintained for up to two hours in 10 of the 12 patients. At five days, SARS-CoV-2 RNA was detected in only 1 patient from the mouthwash group and in 5 from the placebo group. Conclusions: This study points out that a CPC mouthwash can reduce the viral load in saliva of COVID-positive patients. This finding may be important in transmission control of SARS-CoV-2. Nevertheless, the clinical relevance of CPC mouthwash-reduction on SARS-CoV-2 shedding in saliva requires further study