Last updated on July 19th, 2020
[UPDATE 7/19/2020: Here’s an article from JAMA (4/29/2020), Moving Personal Protective Equipment Into the Community: Face Shields and Containment of COVID-19. Bottom line: face shields are likely to be more effective than cloth masks at slowing the spread, especially because they lessen the chances of touching one’s face (and the bacteria-collecting mask). A linked article on Turbulent Gas Clouds and Respiratory Pathogen Emissions points out the vital importance of social distancing, especially around symptomatic persons.
We’ve settled on Instashield (that’s not an affiliate link – ’cause they don’t have one LOL) for our family. My girls may keep wearing cloth masks at work because the shields they’ve tried before are too flimsy for windy days here. If you wear a cloth or surgical mask, the BMJ Open study of cloth masks recommends having two masks. Change daily, and wash and dry thoroughly before reuse. (My girls go through two masks a day at work, changing out whenever the mask gets sweaty and gross.)
Also, please DO NOT WEAR MASKS WHEN YOU ARE ALONE. You don’t need to wear a mask if driving alone in a car, or out for a walk, and it’s unwise to do so. If it’s an N95 mask, you could pass out and crash. Even if it’s just a cloth mask, you’re restricting airflow. Masks are for when social distancing isn’t possible. As soon as it is possible, remove your mask and get some good fresh air in your lungs!]
And Now, On to the Original Post
WOW. This is the most thorough research I’ve seen anywhere. Mask commentary from two experts on respiratory protection. (article updated July 16th, 2020):
In summary, though we support mask wearing by the general public, we continue to conclude that cloth masks and face coverings are likely to have limited impact on lowering COVID-19 transmission, because they have minimal ability to prevent the emission of small particles, offer limited personal protection with respect to small particle inhalation, and should not be recommended as a replacement for physical distancing or reducing time in enclosed spaces with many potentially infectious people. We are very concerned about messaging that suggests cloth masks or face coverings can replace physical distancing. We also worry that the public doesn’t understand the limitations of cloth masks and face coverings when we observe how many people wear their mask under their nose or even under their mouth, remove their masks when talking to someone nearby, or fail to practice physical distancing when wearing a mask.Lisa M Brosseau, ScD, and Margaret Sietsema, PhD, Center for Infectious Disease Research and Policy, COMMENTARY: Masks-for-all for COVID-19 not based on sound data (Updated July 16, 2020)
[I’m not sharing this to debate one way or the other. Only hoping to help folks on both sides understand and show a little more grace to each other. Let’s assume those who disagree with our conclusions have also done their research, and want what is best, and skip the name-calling. You’ll be happier.]
Note: this COMMENTARY article is really two articles, the update & references followed by the original & references.
The article is quite timely because a friend’s copy-paste “by an MD” Facebook post points to the second wave of the Spanish flu as a reason to *mandate* masks:
The 1918-1920 flu pandemic came in three major waves. After the first wave in the US, the virus subsided, and Americans were restless to have businesses reopened and for social life to resume. There was a growing movement to stop wearing masks, which had become ubiquitous – so much so that The Anti-Mask League of 1919 was formed. There were protests from those who thought the public health ordinance violated their liberty.
The virus came back with a vengeance in the fall and was much deadlier than the first wave, eventually killing more than 675,000Americans and killing around 100 million of the 500 million it infected worldwide before it was over.
This was before mass vaccination, before the electron microscope; this is the tragedy of herd immunity and stubborn ignorance. Viruses aren’t political; they don’t care about our theories or speculations or projections. They’re unthinking parasites only wanting to replicate and use your body as a host. Wear a mask.”Facebook “from an MD” copied post
Very persuasive, except for one thing. The doctors in 1920 concluded the masks had no effect on the epidemic curve.
“Kellogg, seeking a reason for the failure of cloth masks required for the public in stopping the 1918 influenza pandemic, found that the number of cloth layers needed to achieve acceptable efficiency made them difficult to breathe through and caused leakage around the mask. We found no well-designed studies of cloth masks as source control in household or healthcare settings.”Lisa M Brosseau, ScD, and Margaret Sietsema, PhD, Center for Infectious Disease Research and Policy, COMMENTARY: Masks-for-all for COVID-19 not based on sound data (Updated July 16, 2020)
I read that 1920 study. It found masks were ineffective even though “cheerfully and universally” worn in public.
Here’s an excerpt:
The failure of the mask was a source of disappointment, for the first experiment in San Francisco was watched with interest with the expectation that if it proved feasible to enforce the regulation the desired result would be achieved. The reverse proved true. The masks, contrary to expectation, were worn cheerfully and universally, and also, contrary to expectation of what should follow under such circumstances, no effect on the epidemic curve was to be seen. Something was plainly wrong with our hypothesis.Kellogg WH, MacMillan G. An experimental study of the efficacy of gauze face masks.Am J Public Health 1920;10(1):34-42
Later, the 1920 study concluded that mandating public masks was ineffective because most spread is with small gatherings, close family or work relationships:
…this form of contact, where people are conversing with one another, would of course, be much more dangerous than crowd association of strangers, even under the circumstances of gathering churches and theaters.Kellogg WH, MacMillan G. An experimental study of the efficacy of gauze face masks.Am J Public Health 1920;10(1):34-42
The experts of this 2020 article DO support masks if mandated. Just please oh please realize your personal hygiene, social distancing, and the building of your immune system are much more effective at keeping you and your loved ones safe.
And if you wear a cloth mask, the BMJ Open Randomized Controlled Trial from 2015 recommends having two masks so you can switch them out daily to wash and completely dry them. (That study found cloth mask-wearing Health Care Workers were 13 times more likely to develop influenza than those with NO masks! Yikes!).
Friend, there IS a risk either way.
If you wear the mask, you risk unknown consequences of incubating bacteria, collecting viruses, and possibly generating an infectious dose on the fomite worn on your face.
If you don’t wear a mask, you risk having to shop online, being called bad names and shamed on social media.
Either way, even hospital masks with gowns were ineffective at stopping the spread of respiratory illnesses like viral influenza among health care workers. Their risk of illness went up, rather, depending on how many hours they spent in the sick wards, regardless of being masked and gowned or not.
There’s a good chance we’ll all be exposed to COVID-19. This is why you need to know about possible early therapies, and do all you can to stay strong.
So please think happy thoughts. Eat well, get your rest, and exercise. And let’s believe the best of our fellow man. We’re all just trying to get through this pandemic as best we can.
Oops. I also found this study, but don’t see it linked in the ones from the COMMENTARY:
Use of surgical face masks to reduce the incidence of the common cold among health care workers in Japan: a randomized controlled trial:
Jacobs JL, Ohde S, Takahashi O, Tokuda Y, Omata F, Fukui T. Use of surgical face masks to reduce the incidence of the common cold among health care workers in Japan: a randomized controlled trial. Am J Infect Control. 2009;37(5):417-419. doi:10.1016/j.ajic.2008.11.002
References – Commentary Update
Anfinrud P, Stadnytskyi V, Bax CE, et al. Visualizing speech-generated oral fluid droplets with laser light scattering. N Engl J Med 2020 (published online Apr 15)
Davies A, Thompson KA, Giri K, et al.Testing the efficacy of homemade masks: would they protect in an influenza pandemic? Disaster Med Public Health Prep 2013 Aug;7(4):413-8
Green CF, Davidson CS, Panlilio AL, et al. Effectiveness of selected surgical masks in arresting vegetative cells and endospores when worn by simulated contagious patients. Infect Control Hosp Epidemiol 2012 May;33(5):487‐94
Johnson DF, Druce JD, Birch C, et al. A quantitative assessment of the efficacy of surgical and N95 masks to filter influenza virus in patients with acute influenza infection. Clin Infect Dis 2009 Jul 15;49(2):275-7
Konda A, Prakash A, Moss GA, et al. Aerosol filtration efficiency of common fabrics used in respiratory cloth masks. ACS Nano. 2020 (published online Apr 24)
Leung NHL, Chu DKW, Shiu EYC, et al. Respiratory virus shedding in exhaled breath and efficacy of face masks. Nat Med 2020 (published online Apr 3)
Ma QX, Shan H, Zhang HL, et al. Potential utilities of mask-wearing and instant hand hygiene for fighting SARS-CoV-2. J Med Virol 2020 (published online Mar 31)
Morawska L, Milton DK. It is time to address airborne transmission of COVID-19. Clin Infect Dis 2020 (published online Jul 6)
National Academies of Sciences, Engineering, and Medicine. 2020. Rapid expert consultation on the effectiveness of fabric masks for the COVID-19 pandemic. Washington, DC, National Academies Press. Apr 8, 2020
Rengasamy S, Eimer B, Szalajda J. A quantitative assessment of the total inward leakage of NaCl aerosol representing submicron-size bioaerosol through N95 filtering facepiece respirators and surgical masks. J Occup Environ Hyg 2014 May 9;11(6):388-96
References – Original COMMENTARY
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