In this paper, researchers discuss how cleaning the sinuses with a simple saline could be useful during the pandemic. They conclude saying that adding anti-viral or virucidal agents to the saline could be beneficial against SARS-CoV-2.

Farrell NF, et al. (2020). Benefits and Safety of Nasal Saline Irrigations in a Pandemic—Washing COVID-19 Away. JAMA Otolaryngol Head Neck Surg., 146(9):787-788.