Facemask use in community settings to prevent respiratory infection transmission: A rapid review and meta-analysis

Abstract

Introduction: Synthesis of the available evidence on the effectiveness of medical and cloth facemask use by the general public in community settings is required to learn lessons for future respiratory epidemics/pandemics.

Method: Search terms relating to facemasks, infection and community settings were used for PubMed, the Cochrane Library Database and Google Scholar. A meta-analysis was conducted using a random-effects model.

Results: The review included 12 primary studies on the effectiveness of medical facemask use to prevent influenza, influenza-like illness, SARS-CoV, and SARS-CoV-2 transmission. The meta-analysis demonstrated that facemask use significantly reduces the risk of transmitting these respiratory infections (pooled OR = 0.66, 95% CI 0.54-0.81). Of the 12 studies, 10 clinical trials suggested that respiratory infection incidence is lower with high medical facemask compliance, early use and use in combination with intensive hand hygiene. One cohort study conducted during the SARS-CoV-2 pandemic demonstrated that facemasks are effective in reducing SARS-CoV-2 transmission when used before those who are infected develop symptoms. One case-control study reported that controls used medical facemasks more often than cases infected with SARS-CoV (p < 0.05). No primary study on cloth facemask effectiveness to prevent respiratory infection transmission was found.

Conclusion: Based on the available evidence, medical facemask use by healthy and sick individuals is recommended for preventing respiratory infection transmission in community settings. Medical facemask effectiveness is dependent on compliance and utilization in combination with preventive measures such as intensive hand hygiene. No direct evidence is currently available in humans supporting the recommendation of cloth facemask use to prevent respiratory infection transmission.

Keywords: Community setting; Facemask; Household.

Figure 1

Meta-analysis on the effectiveness of medical facemasks in preventing respiratory infections in community settings, by type of infection. Meta-analysis conducted based on the random-effects model to compute pooled ORs and their 95% CI. To calculate pooled ORs for all respiratory infections (influenza, influenza-like-illness (ILI), COVID-19, and SARS), all studies eligible for meta-analysis were used. Eligible studies in the meta-analysis are those reporting the number of respiratory infections among the facemask and control groups. To explore the heterogeneity between studies, a sub-group analysis was conducted. Meta-analysis was conducted using only randomized clinical trials assessing the effectiveness of medical facemasks in preventing influenza and in preventing ILI, separately.

Figure 2

Meta-analysis on the effectiveness of medical facemask use in preventing transmission of respiratory infections (a) to apparently healthy individuals having no identified infected close contacts and (b) to close contacts of infected individuals in community settings. The random-effects model was used in this meta-analysis to compute pooled odds ratios (OR) to assess the effectiveness of medical facemask use in preventing primary and secondary transmission of respiratory infections, separately.Meta-analysis on the effectiveness of medical facemask use combined with handwashing in preventing transmission of respiratory infections in community settings.

Figure 3

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