Povidone Iodine Nasal Irrigation and Gargling to Reduce Viral Load in Asymptomatic Patients With COVID-19

The emergence of a novel coronavirus(SARS-CoV-2) in late 2019 has resulted in a global epidemic of the infectious condition COVID-19. Since March 2022, the Omicron mutant has caused widespread transmission in Shanghai, China, and is characterized by the majority of asymptomatic patients. Although showing no obvious symptoms, the asymptomatic patients have high transmissibility because of high viral loads in their oropharynx and nasopharynx. Therefore，this study puts forwards the hypothesis that local flushing treatment in the sino-nasal and mouth cavity can reduce the viral load to reduce their transmissibility. Nasal Irrigation and gargling is a safe and commonly used mechanism to treat a variety of sinonasal diseases including sinusitis, rhinitis, and upper respiratory tract infections. Povidone-iodine(PVP-I) is a water-soluble complex of povidone, a carrier molecule, and iodine, which has powerful microbicidal activity. Also, recent evidence of in-vitro virucidal action of povidone-iodine in Severe Acute Respiratory Syndrome-Coronavirus 2 (SARS CoV-2) has been supported. Therefore, the study is designed to assess the virucidal effect of nasal irrigation and gargling with PVP-I against SARS-CoV-2 located in the throat. The hypothesis was that the treatment would be effective in improving the negative conversion rate of SARS-CoV-2 nucleic acid on day 10.