Researchers from the canadian McMaster University has studied the effectiveness of cloth masks in the fight against the spread of coronavirus.
As reported by Annals of Internal Medicine, the tissue does not stop isolated virions. However, a significant part of the virus is transmitted in droplets, which occur during talking, eating, coughing and sneezing or aerosol particles that can be formed when the liquid evaporates.
the authors of the study stress that the mask can’t block all the infectious agents, but it still holds some of them, especially if we are talking about the spread of the virus an infected person outside.
“the Fabric can block droplets and aerosols, and layers enhance efficiency. Filtration efficiency for individual layers of different types of cotton fabrics in the experiment with bioaerosols (0.2 µm) ranged from 43 to 94 percent, compared with 98 to 99 percent for the fabric of disposable medical masks”, – stated in the publication.
it Also reported that single layers of scarves, sweatshirts, t-shirts and towels had a filtration efficiency of 10 to 40 percent in experiments using NaCl aerosol (0,075 µm). Study 2020 confirms that some fabrics even a single layer of block percentage of transmission aerosols, called clinically useful, and several layers enhance their efficiency.
the authors of the material in the illustrative example experiments on animals, during which the cloth masks prevent the spread of aerosolized tubercle bacilli. As experimental animals used rabbits that were exposed to infected aerosol particles. This was done with tight gauze mask with three and six layers. The experiment revealed the filtration efficiency of these masks to 95 percent.
Scientists admit that the use of cloth masks may be incorrect and can lead to a false sense of security and reduce the level of hygiene, but these effects can be mitigated by educating the population and providing the necessary social pressure. In General, the researchers believe that the possible benefits of cloth masks that let moderately, but still reduce the spread of the epidemic, outweighs the possible negatives.
