It seems only skeptical of cloth masks as compared to surgical masks, which isn’t really very interesting to me in the current circumstances, since most people don’t have access to surgical masks.
The study design does not allow us to determine whether medical masks had efficacy or whether cloth masks were detrimental to HCWs by causing an increase in infection risk. Either possibility, or a combination of both effects, could explain our results. It is also unknown whether the rates of infection observed in the cloth mask arm are the same or higher than in HCWs who do not wear a mask, as almost all participants in the control arm used a mask. The physical properties of a cloth mask, reuse, the frequency and effectiveness of cleaning, and increased moisture retention, may potentially increase the infection risk for HCWs. The virus may survive on the surface of the facemasks,29 and modelling studies have quantified the contamination levels of masks.30 Self-contamination through repeated use and improper doffing is possible. For example, a contaminated cloth mask may transfer pathogen from the mask to the bare hands of the wearer. We also showed that filtration was extremely poor (almost 0%) for the cloth masks. Observations during SARS suggested double-masking and other practices increased the risk of infection because of moisture, liquid diffusion and pathogen retention.31 These effects may be associated with cloth masks… The study suggests medical masks may be protective, but the magnitude of difference raises the possibility that cloth masks cause an increase in infection risk in HCWs.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4420971/ is skeptical of cloth masks. Does anyone have any thoughts on it, or know any other studies investigating this question?
It seems the primary argument for clothing masks that’s made is that if an infected person wears them it’s less likely that they will infect others.
That’s not the purpose that was tested in “A cluster randomised trial of cloth masks compared with medical masks in healthcare workers” that study seemed more about whether or not the masks have protective qualities for the wearer.
It seems only skeptical of cloth masks as compared to surgical masks, which isn’t really very interesting to me in the current circumstances, since most people don’t have access to surgical masks.
No, it says:
Mea culpa, that’s more of a condemnation than I thought.
I noticed this too. When wearing a bandana as a mask, humidity is building up while exhaling, causing it to be slightly damp.