Surgical masks are designed to protect the surgeon from droplets of blood, pus or other bodily fluids. These molecules are relatively large. The masks are not designed to protect the wearer from viruses. Ironically, when there is a risk of a viral outbreak many people, especially in Asian communities, opt to wear facemasks. These masks confer little protection in their unmodified form.
To overcome this limitation, researchers have discovered that the anti-viral properties of the ordinary facemask can be enhanced through the addition of salt. The idea was developed by Professor Hyo-Jick Choi from the University of Alberta in Edmonton.
Professor Choi, Laboratory Roots reports, had been working on oral vaccine development when he noted that crystalized liquids can inactivate some viruses. This led him to look at facemasks, where he discovered that when salt is added to surgical mask filters it inactivates the virus. This happens when a respiratory droplet that contains a virus falls onto the salty filter then as the liquid evaporates the salt crystallizes, destroying the viruses.
To test out the effectiveness Professor Choi’s research team exposed mice to a dose of aerosolized H1N1 influenza virus. One group of mice were exposed via an untreated filter and the second group were exposed through the salt-treated filter. The mice expose through the untreated filter died; whereas the mice exposed through the salt-enhanced filter all survived.
The masks were also examined to see how the virus was deactivated. Here it was found when the virus is adsorbed onto untreated filters, the virus lost just eight percent hemagglutination activity. Whereas with the salt-treated filters, all lost virtually all hemagglutination activity was lost within five minutes. When the viruses were studied under an electron microscope it was found the salt-treated filters physically damaged the virus particles.
Professor Choi plans to commercialize the technology. The research is published in Nature Scientific Reports, in a paper titled “Universal and reusable virus deactivation system for respiratory protection.”
