This paper provides a bit of background to the science and politics behind face coverings and their use in the UK.
The paper was prepared by Scientific Pandemic Influenza Group on Behaviours on the evidence about the behavioural impact of recommending mask use, reflecting the potential for both positive and negative outcomes. It was discussed at SAGE 27 (Scientific Advisory Group for Emergencies) on 21 April 2020. It should be viewed in context: the paper was the best assessment of the evidence at the time of writing. The picture is developing rapidly and, as new evidence or data emerges, SAGE updates its advice accordingly.
Therefore, some of the information in this paper may have been superseded and the author’s opinion or conclusion may since have developed.
These documents are released as pre-print publications that have provided the government with rapid evidence during an emergency. These documents have not been peer-reviewed and there is no restriction on authors submitting and publishing this evidence in peer-reviewed journals.
• SPI-B have not conducted a rapid evidence review of behavioural science considerations relating to facemasks. Instead, we considered the Edinburgh rapid evidence review dated 7 April 2020 and previously provided to SAGE, as well as the NERVTAG paper of 17 April 2020 and summary note of ECDC pros and cons presented to SAGE. We note that in terms of evidence around behavioural science, the Edinburgh review found little evidence and cautioned that what evidence does exist relates to “very specific contexts” which limits generalizability.
• We considered that a ‘community setting’ should not be viewed as a single setting or context. There are a number of different settings and situations where there are higher risks of transmission or difficulties in maintaining social distancing, e.g. those working in shops who are interacting with people much more than people who only leave the house to exercise outdoors or buy food or other essentials.
• A number of hypotheses were discussed about the behavioural impact of recommending mask use, reflecting the potential for both positive and negative outcomes. It is important to emphasise that we are unaware of evidence relating to these hypotheses. However, discussing them may allow the Government to reduce any risk of negative behavioural consequences, and promote any positive aspects.
• Wearing facemasks outside of the house could complement existing government messaging of social responsibility if communicated alongside the effectiveness of masks in protecting others who are not infected. Wearing a facemask could demonstrate that an individual is concerned for other peoples’ welfare and is enacting desired social norms around safety and hygiene.
• However, there are also a number of issues, risks and potentially harmful behaviours associated with recommending or mandating use of facemasks which could reduce their effectiveness:
o Misuse of facemasks/people wearing facemasks incorrectly/reusing facemasks in the absence of very clear guidance on use and disposal, leading to them performing less effectively as a barrier to viral transmission
o Touching facemasks when wearing them or taking them off and putting them on surfaces after taking them off, all of which could contaminate hands and fomites and lead to viral transmission
o Availability of adequate commercial or homemade facemasks, leading to ineffective homemade masks or reuse of masks
o People may feel falsely reassured by wearing facemasks and so pay less attention to other behaviours that reduce viral transmission e.g. wash their hands less, do not adhere to social distancing measures.
• Government should also consider wider possible implications of recommending/mandating the use of facemasks on public behaviour: o Inequity of access for those unable to buy/make facemasks who might therefore be unable to go outside or buy essentials o Heightened public awareness, negative evaluation and harassment of people who are not wearing facemasks, leading to division which could undermine collective solidarity which is helpful for managing the pandemic o Policing implications if people are covering their face
• If government is to recommend that the public wear facemasks in the community, there will need to be thorough guidance and communication on the rationale for changing government advice, and education and training in terms of:
o when and how people should wear masks,
o when and how to dispose of masks,
o any risks associated with their use,
o the possible benefits to themselves or others,
o the need for all other personal protective and social distancing behaviours to be maintained,
o and consideration of an ‘exit strategy’ for masks – determining and articulating at what point would they no longer be recommended?