Here is a short summary from the web about how salt impacts viruses.
Additional links:
https://www.sciencedaily.com/releases/2017/01/170105160228.htm
https://www.cooperhealth.org/patients-visitors/coronavirus-covid-19-information
https://www.nature.com/articles/srep39956
YouTube video
University of Alberta materials engineering professor, Hyo-Jick Choi, has come up with an innovative solution that turns the masks into virus killers. Existing masks and respirators may trap virus-laden droplets but the virus is still infectious on the mask. Choi took on the challenge of improving the masks, using a simple weapon: salt.