talk about "masks" you're going to need to be way more specific.
the vanity masks that most people wear? not at all effective and there is evidence that they are actually harmful and harbor bacteria.
people touch them constantly, rarely wash or change them out, drop them, stored them in their dirty pocket or purse or car cup holder, wear them below the nose, don't wash their hands before or after touching them. etc etc etc.
https://pubmed.ncbi.nlm.nih.gov/25903751/
Conclusions: This study is the first RCT of cloth masks, and the results caution against the use of cloth masks. This is an important finding to inform occupational health and safety. Moisture retention, reuse of cloth masks and poor filtration may result in increased risk of infection. Further research is needed to inform the widespread use of cloth masks globally. However, as a precautionary measure, cloth masks should not be recommended for HCWs, particularly in high-risk situations, and guidelines need to be updated.
Edited by blake1771 at 12:34:12 on 08/05/21