By Ted S. Hall, PE, and Susan Hall, RN, Darby
Comments on Letter to the Editor (September 9, 2020), titled: “Hopkins Mistaken” by Michael Lesner. Subject: The effectiveness of face masks as pertains to protection against COVID-19.
Mr. Lesner states: “Face Masks are ineffective and are driven by politics, not science, in Washington D.C.”
Mr. Lesner’s incorrect statement above and ill-informed letter are unfortunate as there is enough misinformation in the community about best practice mitigation to protect against COVID-19, without him adding to the misinformation.
Two-ply face coverings are quite effective at protecting against COVID-19. Science has determined that if 95% of Americans wore these face coverings, the COVID-19 virus would be effectively controlled and deaths would be reduced.
The Science:
Cloth face mask study at University of San Francisco (Ref. USF Data Scientist Launches #Masks4ALL).
Professor Jeremy Howard was teaching a class (April 2020) on “Deep Learning” on how to use evidence to make decisions. Howard wanted to explore whether wearing masks could help slow the spread of the coronavirus infection (COVID-19).
Prior to early this year, most studies had compared cloth mask coverings to surgical masks and N-95 masks. The early studies found the surgical and N-95 masks “much more effective than cloth masks.” As a result, many medical institutions (but not all) recommended against the public using face masks. This swept the social media as a verdict against the use of cloth face masks. BUT at the end of these well respected medical studies there appears two important details (missed by many readers), regarding the cloth face coverings.
1) At the time of the studies, there was a shortage of the traditional PPE face masks (surgical and N-95). Thus, medical institutions feared that there would be a run on these scarce and important safety devices needed for front line health care workers.
2) Medical professionals were afraid (with no proven justification) that if the public thought a face mask would protect them, they would cease social distancing.
(University of Minnesota Commentary: “Masks for All COVID-19 Not Based on Sound Data”, April 1, 2020 -CIDRAP- Center for Infectious Disease Research and Policy) July 16, 2020: This study was re-issued with a “mask support” statement and cloth mask study data, that supports the use of cloth masks.
Until the University of San Francisco Cloth mask study, nobody had done a study of cloth masks versus no masks. All the previous studies I reviewed compared cloth masks to the surgical and N-95 masks. Consequently, the incorrect fear of PPE shortages and reduced social distancing led to the ill-advised finding against cloth masks.
Today, medical institutions now recommend the use of cloth face coverings as they have been shown to be quite effective at reducing (not eliminating) the droplets that carry COVID-19. So effective, that if 95% of Americans were to wear these cloth masks, the virus would be effectively controlled. Again, THE VIRUS WOULD BE ELIMINATED. (July 14, 2020 STAT – Boston Globe media partner).
As far as Mr. Lesner’s hygiene questions about masks. Cloth masks need to be washed daily. It is easy to use two masks on alternate days.
The breathing and re-breathing of air comment by Mr. Lesner is not an issue because the mask takes the droplets that carry the virus out of the air and they remain on the mask until washed.
One wears a mask to reduce droplet transmission so it is entirely appropriate when in a public space to wear a mask, especially an indoor space.
Contrary to Mr. Lesner’s statement regarding CDC advice, the CDC does recommend cloth face coverings when in public spaces along with maintaining social distancing and staying away from super spreader events such as large groups partying indoors. Yes, CDC recommends that people wear cloth face coverings in public settings and when around people who don’t live in their household, especially when other social distancing measures are difficult to maintain. (CDC July 13, 2020)
In closing, at a hearing in the US Congress (9/16/20) and under oath, Dr. Redfield (head of the CDC ) stated: “This face mask is more guaranteed to protect me against COVID than when I take a COVID vaccine.” WEAR A MASK!