Testing the Efficacy of Homemade Masks: Would They Protect in an Influenza Pandemic?

Abstract

Our findings suggest that a homemade mask should only be considered as a last resort to prevent droplet transmission from infected individuals, but it would be better than no protection.

To mask or not to mask: Modeling the potential for face mask use by the general public to curtail the COVID-19 pandemic

“…Our theoretical results still must be interpreted with caution, owing to a combination of potential high rates of noncompliance with mask use in the community, uncertainty with respect to the intrinsic effectiveness of (especially homemade) masks at blocking respiratory droplets and/or aerosols, and even surprising amounts of uncertainty regarding the basic mechanisms for respiratory infection transmission [4,41]. Several lines of evidence support the notion that masks can interfere with respiratory virus transmission, including clinical trials in healthcare workers [3,4], experimental studies as reviewed [12,10,9,15,11], and case control data from the 2003 SARS epidemic [1,2]. Given the demonstrated efficacy of medical masks in healthcare workers [3], and their likely superiority over cloth masks in [5], it is clearly essential that healthcare works be prioritized when it comes to the most effective medical mask supply.…”

“…The fit factor for homemade masks averaged 2 in [9], while the fit factor averaged 5 for surgical masks. When volunteers coughed into a mask, depending upon sampling method, the number of colony-forming units resulting varied from 17% to 50% for homemade masks and 0-30% for surgical masks, relative to no mask [9].…”

“…Under the ongoing COVID-19 pandemic (caused by the SARS-CoV-2 coronavirus), recommendations and common practices regarding face mask use by the general public have varied greatly protect against droplets/aerosols and viral transmission, but experimental results by Davies et al [9] suggest that while the homemade masks were less effective than surgical mask, they were still markedly superior to no mask. A clinical trial in healthcare workers [5] showed relatively poor performance for cloth masks relative to medical masks.…”

Simplified models for exhaled airflow from a cough with the mouth covered

“…Davies et al. () further compared the surgical and homemade mask and found that the surgical mask was three times more effective in blocking transmission than the homemade mask. Furthermore, the fit performance of a mask can significantly affect the effectiveness of removing exhaled particles (Mansour and Smaldone, ).…”

Cellulose-based virus-retentive filters: a review

“…First worn by surgical teams a hundred years ago to prevent bacterial contamination of patient's open wounds, early surgical masks were constructed from layers of cellulose materials, more particularly cotton cellulose (gauze) (Haller and Colwell 1918) and derivatives (Arnold 1938) (see also Belkin 1997). Much more recently, face masks made from cotton fabrics have been tested as alternative respiratory protective equipment against pandemic outbreaks such as influenza (Dato et al 2006;Davies et al 2013;Rengasamy et al 2010). Like respirators, current commercially available surgical face masks include several layers of non-woven fabrics with, frequently, a cellulose inner layer in contact with the wearer's face to improve wearer's comfort.…”