Face masks for the public during the covid-19 crisis
BMJ 2020; 369 doi: https://doi.org/10.1136/bmj.m1435 (Published 09 April 2020) Cite this as: BMJ 2020;369:m1435Read our latest coverage of the coronavirus pandemic
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Dear Editor,
Admittedly I cannot offer any statistic at this point but it seems clear, from my casual observations in everyday life, outpatient waiting rooms and consultations, that more elderly individuals are far more likely to wear masks below the nose.
It seems very unlikely that this is due to an intentional lack of compliance, particularly as there is some evidence that mask-wearing correlates positively with age (1). It must be the case that there is some impediment to effective mask position in this age group. Could this relate to facial atrophy, reduced dexterity or orofacial apraxia, for example? This deserves to be further explored.
1. Haischer MH, Beilfuss R, Hart MR, Opielinski L, Wrucke D, Zirgaitis G, Uhrich TD, Hunter SK. Who is wearing a mask? Gender-, age-, and location-related differences during the COVID-19 pandemic. PLoS One. 2020 Oct 15;15(10):e0240785. doi: 10.1371/journal.pone.0240785. PMID: 33057375; PMCID: PMC7561164.
Competing interests: No competing interests
Dear Editor,
WHY was this article not brought to the attention of senior government advisers at the time?
The human race being, in the main, non-compliant, the stance on covid should have been ‘elimination’ through legal measures.
VIRUS BREAK PERIOD
Enforcing masks to be properly worn by all, everywhere, for 14 day periods. It is easy to control with immediate on the spot fines and results measurable within this specific timeframe.
WHY do the mask manufacturers only test in a singular mask setting when they should be testing in a simulated ‘one person with a virus’ to a ‘group without the virus’ - group testing setting?
Results would show a dramatic increased efficacy from the single wearer of a mask passing on a virus to a non mask wearer and comparing that result against that of a mask wearer - in both an indoor situation and an outdoor situation.
Thank you to the original writer - MOST impressed.
Competing interests: No competing interests
Dear Editor, much time - and general scientific opinion - has moved on significantly in this debate since this article was published.
The UK Government finally decided on 14.7.2020 to enforce face covering by law in shops and supermarkets from 24.7.20.
Given the short notice given for other more far reaching decisions during this Pandemic it is hard to understand a 10 day delay was needed to bring this long overdue policy into force. A simple change in advice, followed by the fine becoming active as of 24th July would have immediately started to change general behaviour and could only have benefited public health. However that is not actually the point of this response.
It intrigues me that in many 'hospitality' settings, and beauty parlours / hairdressers the decision has been taken to wear VISORS rather than masks / face coverings. The UKG own public health messages show barbers in face shields / visors only https://twitter.com/DHSCgovuk/status/1285137371089043456?s=20
There are some obvious advantages to visors, including for example: better communication, easier to wear over beards, do not fog up with glasses, more comfortable for long shifts, perhaps re-enforce social distancing and certainly more likely protect the wearer from splashes to the mucous membranes and make it less likely to touch your face than if wearing a mask.
However it is also very likely that visors /shields are not as effective at preventing the onward spread of viral particles to others. Indeed if worn by a waiter or hairdresser for example they may indeed funnel and concentrate exhaled air downwards towards your food / your clients face.
There have already been reported concerns from Switzerland where an outbreak of Coronavirus was linked to face shields. Their advice there is now to combine visors with a face mask. https://www.thelocal.ch/20200715/only-those-with-plastic-visors-were-inf...
A report in JAMA networks discussed the potential benefits of visors for the WEARER only https://jamanetwork.com/journals/jama/fullarticle/2765525
GIven that we are about to adopt a national policy, surely we should 'follow the science' and ask those wearing face shields for their own comfort and protection to also add a mask where they are either handing our food or unable to maintain safe social distancing to ensure that we reduce the chances of onwards spread and protect those around us ?
I would welcome the views and opinions of those for more knowledgeable in this area, but would like to see the public as protected as possible, and where social distancing is not possible we must ensure safe and effective face covering is recommended in all closed public settings.
Yours sincerely
SImon Hodes
GP, Bridgewater Surgeries, Watford
Competing interests: No competing interests
Dear Editor,
The debate about the effectiveness of face masks continues. I continue to find it curious that arguments in favour of masks are made purely on the basis of its efficacy when properly worn. How the mask is handled by people when conducting everyday tasks is seldom factored into the consideration. For example, how many times do we see people touching their mask and nose in quick succession while removing the mask (especially when they do it with one hand while the other hand is holding something else)? Recommendations should take into consideration people’s actual behavior in everyday life and compliance with good practice, even if wearing mask itself works.
In my current visit to Norwich, I can see that at the entrance of most shops, there are hand sanitiser dispensers, and customers observe physical distancing rather well so far as it is permissible. The contrast with the situation on the streets, however, is apparent. While physical distancing is mostly observed by people through self-discipline, hand sanitiser dispensers are nowhere to be found.
Considering how inexpensive it is to install things like free alcohol dispensers on streets and in parks, and the potential public health benefit, not only at this juncture but in the long-term, it is curious why governments around the world have not done it. As it is increasingly evident that masks are not necessarily well-tolerated at all times by all people,1 such a measure may help to reduce contamination of surfaces, a possibly major route of transmission, through encouraging more frequent hand cleaning on a massive scale.
1Cheng S-T. Covid-19: are face masks a good long term strategy? BMJ 2020;369:m2005. doi:10.1136/bmj.m2005 pmid:32434836
Competing interests: No competing interests
Dear Editor,
There is a particular form of logical fallacy that goes, 'nobody fully understands the consequences so the precautionary principle demands that we follow my favored option'. It is frequently used in technology discussions in cases where the speaker knows that expert opinion rejects their favored option and it is therefore necessary to begin by discounting the existence of relevant experience or expertise.
I am a security specialist with over 30 years experience in the field. I have designed and deployed security infrastructures for governments, enterprises and individuals. I was the security specialist on the team that developed the World Wide Web first at CERN and then at MIT when the Web Consortium was formed there. Understanding how humans interact with the security systems I build is a large part of my work.
The term 'false sense of security' is one that I have heard frequently in my career. While it might seem obvious that providing a security control encourages people to take risks that they would not take otherwise, in security, what is 'obvious' frequently turns out to be wrong.
Humans are not rational actors. In the field of economics, the assumption that humans behave as rational actors can in certain circumstances serve as a modelling approximation that while obviously incorrect may provide valid results. But the fact that an approximation leads to the correct result does not mean that the approximation is truth. I have yet to encounter a proponent of the 'Rational Choice' school of information security. If only humans were rational actors, it would make our work considerably easier.
In the field of information security, it is familiarity rather than the provision of security controls that typically leads to complacency. Consider the recent concern about the lack of 'end-to-end' encryption in a video conferencing service. While the security concerns stated are valid almost every person venting about the lack of end-to-end security in that communications product has been using SMTP email which shares the exact same security weakness for decades and for purposes that are considerably more sensitive.
On occasion, a client will demand that I provide a fax number so that they can send me a document 'securely' rather than trusting it to the Internet. A precaution that makes precisely no sense as the vast bulk of telephone traffic has been carried over the Internet for more than a decade.
While it is possible that people wearing masks will take risks that they would not take otherwise, there is no evidence showing that this is the case and very good reason to expect the opposite.
In the wake of 9/11, many people, myself included wore US flag pins. Not because these would provide any protection against terrorist attack but as a reminder of the present purpose. Environments where everyone is wearing a mask provide constant reminders of the situation and reinforcement of the need to be cautious. Environments where nobody is wearing a mask provide neither.
Anecdote is a poor guide to policy. The best way for governments to encourage compliance with public safety measures is to lead by example and to emphasize the need for constant vigilance. We should not reject security controls out of anecdotal concerns about a false sense of security. Instead make masks a reminder of the need for that vigilance to both the wearer and everyone they meet.
Competing interests: No competing interests
Dear Editor,
In a prescient piece published in BMJ on April 9, 2020, Professor Greenlaugh et al argued for policy recommending masks for the general public to prevent the transmission of COVID-19 [1]. Since that time, the body of literature, and government endorsement within various international jurisdictions, has caught up to this point of view [2]. As we begin to emerge from various states of isolation and physical distancing, with the shadow of second waves ever present, we can anticipate that masks will now remain an integral part of our lives throughout the world. Widespread donning of masks will impact how we function and move through many facets of society, not least of which how healthcare is accessed (as patient) and delivered (as provider). Such protective measures necessary to sustain public safety have specific implications for health professional education.
The OSCE or objective structured clinical exam model is used by health disciplines to test clinical skills, knowledge, and performance [3]. Examinees proceed through a series of stations (usually small physical spaces) interacting with a patient actor or examiner (in relative close proximity) for approximately 10 minutes each. While most stations require direct communication between individuals, some encounters also include a clinical examination. The OSCE is an assessment modality deployed within various health professional curriculum, as well as by professional licensing bodies globally …and these have been summarily suspended in the face of COVID-19. Certainly, a number of programs have pivoted to skills assessment online just as patient care delivery through virtual platforms has escalated in these past months. However, given the advantages of high-fidelity situations for standardized assessment of direct patient care, and practical limitations to simulating aspects of healthcare that must be conducted in person, it is highly likely OSCEs will resume in some form in the future. These conditions will assuredly entail physical distancing and masks to ensure the safety of participants. As our faces are central to both verbal and non-verbal communication in person-centred care–the empathetic tone, a reassuring expression or understanding smile - how will we judge trainees now?
Conducting health professional competency assessment in settings where full facial expressions are obscured is in fact not new. Examples of OSCEs in regions where cultural dress covers partial or full views of the face exist and may provide guidance for assessing communication skills elsewhere. Evidence suggests that examiners from diverse cultural backgrounds can adapt to environments where an individual without full facial exposure engages patients, but the assessment instruments require refinement to accurately rate this performance [4]. Instead of deconstructing communication into individual components, for example, tools should instead target more global constructs such as confidence, development of rapport, and adaptability. Examiners will also need guidance on how to reconcile traditional perspectives of what behaviours constitute competent communication with those now required for practice in the post-COVID era. Moving forward, health professional programs must attend to the development of such expanded skillset among trainees (e.g. greater emphasis on eyes and voice), as well as to the re-orientation of examiners adjusting to altered communication norms between patients and practitioners wearing personal protective equipment. Revising scoring tools to encompass more holistic assessment of competent communication may be a starting point to ensure robust assessment of professional performance [5].
References
1. Greenhalgh T, Schmid MB, Czypionka T, et al. Face masks for the public during the covid-19 crisis. Bmj 2020;369:m1435. doi: 10.1136/bmj.m1435 [published Online First: 2020/04/11]
2. Chu DK, Akl EA, Duda S, Solo K, et al. Physical distancing, face masks, and eye protection to prevent person-to-person transmission of SARS-CoV-2 and COVID-19: a systematic review and meta-analysis. The Lancet 2020; https://doi.org/10.1016/S0140-6736(20)31142-9 [published Online First: 2020/06/01]
3. Harden RT, Stevenson M, Downie WW, Wilson GM. Assessment of clinical competence using objective structured examination. Br Med J 1975;1(5955):447–451.
4. Wilby KJ, Diab M. Key challenges for implementing a Canadian-based objective structured clinical examination (OSCE) in a Middle Eastern context. Can Med Educ J. 2016;7(3):e4-9.
5. Wilby KJ, Govaerts M, Austin Z, Dolmans D. Discriminating features of narrative evaluations of communication skills during an OSCE. Teach Learn Med 2019;31(3):298-306
Competing interests: No competing interests
Dear Editor,
Greenhalgh et al. [1] advised that face masks should be worn in public to prevent some transmission of COVID-19 in the context of a return to normal life and economic activity. Protective masks have thus become everyday objects, reassuring as a prophylactic measure for some while constraining for others. King [2] pointed out that wearing masks may be problematic in altering the role of facial expressions.
Facial expressions are trans-cultural and consist of reactions to seven emotions--anger, contempt, disgust, fear, joy, sadness, and surprise. They are the most powerful, natural, and direct way to communicate emotion in everyday social interactions. We wish to highlight that while reading these expressions has a central role in traditional psychiatric evaluation, we may wonder how wearing faces masks for both patients and doctors may modify psychiatric care, whereas the psychological impact of the crisis (i.e depression, anxiety) has become a public health priority.
Wearing a face mask will complicate psychiatric assessment as it will reduce facial expressivity in reaction to emotional stimuli and during social interactions. The mouth which is one of the most important area for decoding emotions from faces will be hidden. Many subtle facial expressions such as twitches of mouth and wrinkling of nose that also convey a range of emotions, will be erased [3]. Doctors will thus have to focus on the eyes, the eyebrows and the forehead and to be more attentive to verbal and non-verbal symptoms (e.g. more downward gazes but also monotone pitch, reduced articulation rate, lower speaking volumes, fewer gestures, to detect depression).
For patients, face masks will increase impaired identification of doctor’s facial expressions. It will difficult for the doctor to express empathy for the patient’s sufferings without showing his expressions, which will again hinder treatment success. For instance, depressed subjects need greater. Usually avoiding to look at the eyes of their counterparts, they will have no other facial cues to detect another’s emotional state. To allow a perceptible expression of the emotion felt, the doctor will need to overexpress it with the voice, attitudes, gestures.
To summarize, wearing a mask may modify our behaviors by reducing our propensity to communicate or by forcing other aspects. To overstep these difficulties, some solutions deserve to be discussed.
First, it could be interesting to develop transparent protection in order to keep the access to complete facial expressions.
Second, we could mix face to face interviews with masks and telemedicine contacts without masks in order to enlarge our semiology.
Third, we could have resort to artificial intelligence-based and digital tools to augment and complement existing clinical methods [4].
1. Greenhalgh T, Schmid MB, Czypionka T, et al. Face masks for the public during the covid-19 crisis. Bmj 2020;369:m1435. doi: 10.1136/bmj.m1435 [published Online First: 2020/04/11]
2. King FM. Covid-19: face masks could foster distrust and blame. Bmj 2020;369:m2009. doi: 10.1136/bmj.m2009 [published Online First: 2020/05/22]
3. Eisenbarth H, Alpers GW. Happy mouth and sad eyes: scanning emotional facial expressions. Emotion 2011;11(4):860-65. doi: 10.1037/a0022758 [published Online First: 2011/08/24]
4. Haque A, Guo M, Miner AS, et al. Measuring depression symptom severity from spoken language and 3D facial expressions. arXiv preprint arXiv:181108592 2018
Competing interests: No competing interests
Dear Editor
We totally agree with the authors when they appeal to the precautionary principle to recommend the use of face masks “outside the home in situations where meeting others is likely (for example, shopping, public transport)” (1). The story of a choir practice with 60 people, of whom 45 are known to have developed covid-19, as well as the coronavirus disease outbreak in a call center (2), are good examples of the high risk of transmission in closed spaces with many people singing or speaking loudly for a long time.
In Spain, the wearing of hygiene masks by the general healthy population was made compulsory on public transport as from 4 May. Later on, the leader of Spain’s main opposition party issued a nationwide demand for “the compulsory wearing of masks in public places and mass testing”. Finally, on 20 May the use of some kind of mask, preferably hygiene or surgical, was made compulsory in Spain for all persons over the age of six, whether in the street, outdoors or in closed spaces used by or open to the public. Generalised use of masks by the general public to reduce community transmission of COVID-19 was justified on the principle of precaution. The argument put forward by those who initially and most energetically defended this measure is extremely attractive and tempting, i.e., mass testing and the compulsory wearing of masks would serve to avoid future lockdowns. If it were in fact true that the use of masks everywhere at every time could prevent a future lockdown, then we ourselves would be the first not to leave home without wearing one. However, this is not the case.
The wide use of masks by healthy people in the community setting is not supported by current evidence, as the authors themselves recognize, and carries uncertainties and risks (3). The potential risks (self-contamination that can occur by touching and reusing contaminated masks and a false sense of security, leading to potentially less adherence to other preventive measures, such as physical distancing and hand hygiene, among others) are much more likely to happen when people are forced to carry face masks all the time, particularly in open spaces where high temperatures make their use very uncomfortable, as is the case in Spain. In this context, for which there is no clear benefit-risk relationship, the application of the precautionary principle becomes more questionable.
Additionally, the substantial financial resources required to maintain the continued use of masks by the general public could be better allocated to other public health measures of tried and tested efficacy, such as the promotion of the appropriate respiratory etiquette and hand hygiene. What is more, if it were to be shown that the benefit of compulsory use of masks in open spaces in Spain was outweighed by the potential risks associated with their misuse (an apparently common phenomenon, judging by what can be seen daily on any city street), we would be confronted with a prejudicial health intervention which failed to comply with the maxim “primum non nocere” (first, do no harm), a precept that should govern all health actions.
With the degree of uncertainty currently surrounding the balance of potential benefits and risks of using face masks by the general population, especially in open spaces, it would seem more prudent to issue flexible recommendations than a set of compulsory measures aimed at restricting individual freedoms. While the precautionary principle may be appealed to to support advice to wear masks in certain circumstances, such as on public transport and in crowded closed spaces, any such recommendation should be combined with suitable information about how to use them and the potential risks of misuse.
Mandatory use of masks in open spaces by the general healthy population in Spain is an intrusive measure that restricts individual freedoms, and would not appear to be justified on the basis of available scientific evidence regarding the potential benefits and risks associated with this practice. Moreover, the compulsoriness of wearing a mask should be accompanied by measures designed to ensure that the entire population, and the lower-income strata in particular, enjoy unrestricted access to these, while simultaneously preventing the possible risk of a shortage—present or future—of surgical masks and respirators. Taking the precautionary principle too far might produce just the opposite consequences of what is intended.
References
1. Greenhalgh T, Schmid MB, Czypionka T, et al. Face masks for the public during the covid-19 crisis. Bmj 2020;369:m1435. doi: 10.1136/bmj.m1435.
2. Shin YP, Young-Man K, Seonju Y, Sangeun L, Baeg-Ju N, Chang BK, et al. Coronavirus Disease Outbreak in Call Center, South Korea. Emerg Infect Dis. 2020;26. doi: 10.3201/eid2608.201274. Online ahead of print.
3. World Health Organization. Advice on the use of masks in the context of COVID-19: interim guidance, 6 April 2020. https://apps.who.int/iris/handle/10665/331693 (accessed 24 May 2020).
Competing interests: No competing interests
I read the well done and much needed review of face masks for covid-19 as well as all of the 66 rapid responses posted to date. While the discussion is excellent with most of the pertinent issues covered, there is one alternative that was not mentioned: If we don't speak or exhale we don't emit coronavirus-containing respiratory droplets, so why don't we simply stop talking and exhaling within 3m of other individuals when the circumstances support doing so?
A typical situation supporting these maneuvers is cycling. At a moderate cycling speed of 16 km/hr less than a second is needed to traverse the 4m (2m approaching and 2m following) required to preserve the usual social distancing recommendation--and greater social distancing limits are easy to achieve. Yet I have not found any CDC , WHO, or other guidances that recommend this simple, noninvasive, universally available, no cost maneuver.
So, if you happen to be on one of the scenic bike paths in the U.S. and you're about to pass by a gray-haired, helmut-wearing senior on a hybrid bike, wave, nod, or give me a thumbs up, but don't talk or exhale. If you can't hold your tongue and your breath for 1 second, then please wear a mask!
Competing interests: No competing interests
Re: Face masks for the public during the covid-19 crisis
Dear Editor
Reading the article and the responses, I am left with the conclusion that there is no conclusive statistical evidence one way or another. I will follow my gut instinct.
If I am likely to be exposed to infection, I will wear the best available mask using it correctly and dispose of it according to the manufacturer‘s instructions. And if I have reason to suspect that I have the infection, I will get myself tested.
Competing interests: No competing interests