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Cited by 120Infection Control and VentilationCOVID-19 epidemiological studiesCOVID-19 impact on air quality

The DOI matches its Crossref record; 71 of the 71 references it cites were found in a registry or an index.

Long distance airborne transmission of SARS-CoV-2: rapid systematic review

Open access
Duval, Daphne, Palmer, Jennifer C, Tudge, Isobel, Pearce-Smith, Nicola, O’Connell, Emer, Bennett, Allan, Clark, Rachel·2022·BMJ
DOI 10.1136/bmj-2021-068743PMC PMC9240778

Published version of a preprint

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Abstract

Objectives: To evaluate the potential for long distance airborne transmission of SARS-CoV-2 in indoor community settings and to investigate factors that might influence transmission. Design: Rapid systematic review and narrative synthesis. Data sources: Medline, Embase, medRxiv, Arxiv, and WHO COVID-19 Research Database for studies published from 27 July 2020 to 19 January 2022; existing relevant rapid systematic review for studies published from 1 January 2020 to 27 July 2020; and citation analysis in Web of Science and Cocites. Eligibility criteria for study selection: Observational studies reporting on transmission events in indoor community (non-healthcare) settings in which long distance airborne transmission of SARS-CoV-2 was the most likely route. Studies such as those of household transmission where the main transmission route was likely to be close contact or fomite transmission were excluded. Data extraction and synthesis: Data extraction was done by one reviewer and independently checked by a second reviewer. Primary outcomes were SARS-CoV-2 infections through long distance airborne transmission (>2 m) and any modifying factors. Methodological quality of included studies was rated using the quality criteria checklist, and certainty of primary outcomes was determined using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) framework. Narrative synthesis was themed by setting. Results: 22 reports relating to 18 studies were identified (methodological quality was high in three, medium in five, and low in 10); all the studies were outbreak investigations. Long distance airborne transmission was likely to have occurred for some or all transmission events in 16 studies and was unclear in two studies (GRADE: very low certainty). In the 16 studies, one or more factors plausibly increased the likelihood of long distance airborne transmission, particularly insufficient air replacement (very low certainty), directional air flow (very low certainty), and activities associated with increased emission of aerosols, such as singing or speaking loudly (very low certainty). In 13 studies, the primary cases were reported as being asymptomatic, presymptomatic, or around symptom onset at the time of transmission. Although some of the included studies were well conducted outbreak investigations, they remain at risk of bias owing to study design and do not always provide the level of detail needed to fully assess transmission routes. Conclusion: This rapid systematic review found evidence suggesting that long distance airborne transmission of SARS-CoV-2 might occur in indoor settings such as restaurants, workplaces, and venues for choirs, and identified factors such as insufficient air replacement that probably contributed to transmission. These results strengthen the need for mitigation measures in indoor settings, particularly the use of adequate ventilation. Systematic review registration: PROSPERO CRD42021236762.

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Crossref · 10.1136/bmj-2021-068743

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Fig 1 Flow of articles through the review
Fig 1 Flow of articles through the reviewCC BY-NC · PubMed Central
Fig 2 Quality assessment. *Assessments using quality criteria checklist (QCC) for primary research (see supplementary material 1). †Critical questions: 2 on selection bias, 3 on group comparability, 6 on description of exposure/assessment of transmission routes, and 7 on validity of outcome measurements
Fig 2 Quality assessment. *Assessments using quality criteria checklist (QCC) for primary research (see supplementary material 1). †Critical questions: 2 on selection bias, 3 on group comparability, 6 on description of exposure/assessment of transmission routes, and 7 on validity of outcome measurementsCC BY-NC · PubMed Central

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Research works printed but not linked: 1

  1. Public Health Agency of Canada . Rapid Review on SARS-CoV-2 Aerosol Transmission, Update 2. 2021. www.nccmt.ca/covid-19/covid-19-evidence-reviews/418.

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Metadata

Authors
Duval, D., Palmer, J. C., Tudge, I., Pearce-Smith, N., O’Connell, E., Bennett, A., & Clark, R.
Affiliations
  • University of Bristol (GB)
  • UK Health Security Agency (GB)
  • COVID-19 Rapid Evidence Service, UK Health Security Agency, London, UK
  • COVID-19 Advice and Guidance, UK Health Security Agency, London, UK
Corresponding author
Duval, Daphne
ORCID
Venue
BMJ
Publisher
BMJ
Published
2022-06-29
Volume
377
Pages
e068743
ISSN
1756-1833 (ISSN-L)
DOI
10.1136/bmj-2021-068743
PMC
PMC9240778
OpenAlex
W4283720276
Cited by
120
References
71
Citations by year
2026: 6 · 2025: 22 · 2024: 41 · 2023: 37 · 2022: 14
FWCI
4.93
Type
journal article
Language
en
Open access
Licence
Locations
  • BMJ (publishedVersion, cc-by-nc)
  • medRxiv (acceptedVersion, cc-by-nc-nd)
  • PubMed Central (publishedVersion, cc-by-nc)
  • PubMed (publishedVersion)
  • Explore Bristol Research (submittedVersion, cc-by-nc)
  • Bristol Research (University of Bristol) (submittedVersion, cc-by-nc)
Funders
  • British Heart Foundation (AA/18/7/34219)
  • University of Bristol (MC_UU_00011/6)
  • Medical Research Council (MC_UU_00011/6, COVID-19, MC_UU_00011)
Topics
  • Health Sciences › Medicine › Pulmonary and Respiratory Medicine › Infection Control and Ventilation
  • Physical Sciences › Mathematics › Modeling and Simulation › COVID-19 epidemiological studies
  • Physical Sciences › Environmental Science › Global and Planetary Change › COVID-19 impact on air quality
Keywords
SARS-CoV-2, airborne transmission, long-distance transmission, aerosols, airflow direction, asymptomatic transmission, pre-symptomatic transmission, transmission risk factors, outbreak investigation, COVID-19 pandemic, restaurants, workplace, choir, singing, loud speech, ventilation, indoor air quality, public health recommendations
MeSH terms
COVID-19, SARS-CoV-2, Aerosols, Disease Outbreaks, Humans

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