Extended use or re-use of single-use surgical masks and filtering facepiece respirators: A rapid evidence review
Toomey E., Conway Y., Burton C., Smith S., Smalle M., Chan XH., Adisesh A., Tanveer S., Ross L., Thomson I., Devane D., Greenhalgh T.
AbstractBackgroundThe COVID-19 pandemic has led to unprecedented demand for personal protective equipment. Shortages of surgical masks and filtering facepiece respirators has led to the extended use or re-use of single-use respirators and surgical masks by frontline healthcare workers. The evidence base underpinning such practices has been questioned.ObjectivesTo summarise guidance and synthesise systematic review evidence on extended use, re-use or reprocessing of single-use surgical masks or filtering facepiece respirators.MethodsA targeted search of the World Health Organization, European Centre for Disease Prevention and Control, the US Centers for Disease Control and Prevention, and Public Health England websites was conducted to identify guidance. Four databases (Medline, Pubmed, Epistemonikos, Cochrane Database of Systematic Reviews) and three preprint repositories (Litcovid, MedRxiv and Open Science Framework) were searched for relevant systematic reviews. Record screening and data extraction was conducted by two reviewers. Quality of included systematic reviews was appraised using the AMSTAR-2 checklist. Findings were integrated and narratively synthesised to highlight the extent to which key claims in guidance documents were supported by research evidence.ResultsSix guidance documents were identified. All note that extended use or re-use of single-use surgical masks and respirators (with or without reprocessing) should be considered only in situations of critical shortage. Extended use was generally favoured over re-use because of reduced risk of contact transmission. Four high-quality systematic reviews were included: three focused on reprocessing (decontamination) of N95 respirators and one focused on reprocessing of surgical masks. There was limited evidence on the impact of extended use on masks and respirators. Vaporised hydrogen peroxide and ultraviolet germicidal irradiation were highlighted as the most promising reprocessing methods, but evidence on the relative efficacy and safety of different methods was limited. We found no well-established methods for reprocessing respirators at scale.ConclusionsThere is limited evidence on the impact of extended use and re-use of surgical masks and respirators. Where extended use or re-use is being practiced, healthcare organisations should ensure that policies and systems are in place to ensure these practices are carried out safely and in line with available guidance.