Key considerations in mass masking during the COVID-19 outbreak: a scoping review

Background

Many countries are gradually returning to normalcy after varying periods under lockdown following the coronavirus disease (COVID-19) pandemic. In the transitional period from lockdown to resumption of work and thereafter, hygiene-oriented measuresincluding face mask usagewill need to be continued by the public. Though mass masking has been suggested to block transmission of COVID-19 infection, there are key considerations that need attention when this strategy is adopted by the general public on a mass scale for a considerable period of time. This study aims to review research evidence pertaining to key considerations related to mass maskingby the general public during the COVID-19 outbreak.

Methods

We carried out a scoping review and identified relevant literature until 30^thof September 2020 searching databases and other sources comprehensively. This scoping review was registered under Open Science Framework and is available on osf.io/vj9a6.

Results

A total of 42 articles were included in this scoping review. Consensus statements and guidelines were common. Evidence specific to COVID-19 is limited.

Conclusion

There is no conclusive evidence of benefits from introduction of mass masking as a single interventionin preventing transmission of viral-borne respiratory infections. However, beneficial effects are noted when mass masking is always combined with other non-pharmacological measures and when used by symptomatic patients as a means of source control of the disease. Evidence of mass masking on preventing transmission of viruses from asymptomatic persons is not available. In addition, cloth masks and homemade masks have varying degrees of effectiveness; however, the protection conferred is inferior compared to that of respirators and surgical masks.