Non-pharmaceutical interventions for COVID-19: a systematic review on environmental control measures

Abstract

The purpose of this review was to identify the effectiveness of environmental control (EC) non-pharmaceutical interventions (NPIs) in reducing transmission of SARS-CoV-2 through conducting a systematic review. EC NPIs considered in this review are room ventilation, air filtration/cleaning, room occupancy, surface disinfection, barrier devices, CO 2 monitoring and one-way-systems. Systematic searches of databases from Web of Science, Medline, EMBASE, preprint servers MedRxiv and BioRxiv were conducted in order to identify studies reported between 1 January 2020 and 1 December 2022. All articles reporting on the effectiveness of ventilation, air filtration/cleaning, room occupancy, surface disinfection, barrier devices, CO 2 monitoring and one-way systems in reducing transmission of SARS-CoV-2 were retrieved and screened. In total, 13 971 articles were identified for screening. The initial title and abstract screening identified 1328 articles for full text review. Overall, 19 references provided evidence for the effectiveness of NPIs: 12 reported on ventilation, 4 on air cleaning devices, 5 on surface disinfection, 6 on room occupancy and 1 on screens/barriers. No studies were found that considered the effectiveness of CO 2 monitoring or the implementation of one-way systems. Many of these studies were assessed to have critical risk of bias in at least one domain, largely due to confounding factors that could have affected the measured outcomes. As a result, there is low confidence in the findings. Evidence suggests that EC NPIs of ventilation, air cleaning devices and reduction in room-occupancy may have a role in reducing transmission in certain settings. However, the evidence was usually of low or very low quality and certainty, and hence the level of confidence ascribed to this conclusion is low. Based on the evidence found, it was not possible to draw any specific conclusions regarding the effectiveness of surface disinfection and the use of barrier devices. From these results, we further conclude that community agreed standards for well-designed epidemiological studies with low risk of bias are needed. Implementation of such standards would enable more confident assessment in the future of the effectiveness of EC NPIs in reducing transmission of SARS-CoV-2 and other pathogens in real-world settings. This article is part of the theme issue ‘The effectiveness of non-pharmaceutical interventions on the COVID-19 pandemic: the evidence’.

COVID-19 Personal Protective Behaviors during Large Social Events: The Value of Behavioral Observations

“…For example, cohorting/batching attendees with managerial and environmental controls appeared to help in managing crowding (and see [28]). More generally, environmental and service restructuring, including seating plans, floor markings, food and beverage delivery (and remote ordering), and physical barriers/pathways, worked well to shape the behaviors of large numbers of individuals.…”

“…The Royal Society recently conducted a series of reviews looking at the efficacy of nonpharmaceutical interventions during COVID-19, which suggested that social distancing measures can be highly effective in mitigating the risk of contagion within a population [18]. Environmental controls may also be advantageous, though more focused research is required in that regard [28]. A separate evaluation on the efficacy of communication strategies to promote personal protective behaviors indicated that government-level communications have generally been effective [46].…”

Estimated relative potential for airborne SARS-CoV-2 transmission in a day care centre

“…Although all the models predict that an increased non-infectious air flow rate will reduce infection transmission, there is a lack of high-quality evidence of the effect of enhanced ventilation and air cleaning on transmission [ 20 ].…”