An extensive review by researchers at the University Hospital of Wales found that many inexpensive mouthwashes can destroy the fatty membrane that surrounds SARS-CoV-2, the virus that causes COVID-19. Previous research showed that mouthwashes such as Cool Mint Listerine were shown to eliminate 99.99% of H1N1 influenza in tissue culture.

According to Forbes, iodine, which is used as a gargle in Japan and India for sore throats, has strong antiviral properties. Hydrogen peroxide at 0.5% concentration may inactivate many viruses that have a fatty membrane surrounding them, including the coronavirus.

A study published in Nature found that nasal irrigation and gargling with saltwater reduced the length of viral illness and lowered the risk of infection by 35% in households. Even gargling with chlorinated tap water reduced respiratory infections, claims a study conducted in Japan.

Forbes reports that a German study found Listerine, Iso-Betadine and Dequonal mouthwashes to be the most effective at combating three strains of SARS-CoV-2. Dr. Valerie O’Donnell, one of the Welsh researchers, stressed the need for urgent clinical trials to test the effectiveness of mouthwashes and nasal sprays against COVID-19.