Eligible patients will be approached and recruited from COVID in-patient wards within Cardiff and Vale University Health Board, Betsi Cadwaladr University Health Board, University Hospitals Bristol NHS Foundation Trust and Cwm Taf Morganwg University Health Board. Only patients who are deemed well enough and able to provide informed consent by their local clinical teams will be approached to take part in the study. Specific inclusion criteria are: 1. Adults aged =18 years 2. With positive SARS-CoV-2 carriage by RT-PCR within 14 days 3. Capable of using the mouthwash required by the trial 4. Capacity and capability to give informed consent to take part in the trial

Eligible patients will be approached and recruited from COVID in-patient wards within Cardiff and Vale University Health Board, Betsi Cadwaladr University Health Board, University Hospitals Bristol NHS Foundation Trust and Cwm Taf Morganwg University Health Board. Only patients who are deemed well enough and able to provide informed consent by their local clinical teams will be approached to take part in the study. Specific inclusion criteria are: 1. Adults aged =18 years 2. With positive SARS-CoV-2 carriage by RT-PCR within 14 days 3. Capable of using the mouthwash required by the trial 4. Capacity and capability to give informed consent to take part in the trial