Evidence map›Paper›PMID 35428628›Full record

ArticleBMJ open2022

Assessing impact of ventilation on airborne transmission of SARS-CoV-2: a cross-sectional analysis of naturally ventilated healthcare settings in Bangladesh.

Ashley Styczynski, Caitlin Hemlock, Kazi Injamamul Hoque, Renu Verma, Chris LeBoa, Md Omar Faruk Bhuiyan, Auddithio Nag, Md Golam Dostogir Harun, Mohammed Badrul Amin, Jason R Andrews

Open access · goldAbstract read
In one paragraph

Article in BMJ open, 2022. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 6 papers.

0numbers the graph read from it
0cells of the map it votes in
6citing papers in PubMed
1.7field-weighted citation impact, top 16% of its field
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

6 citing papers in PubMed, 11 citations in OpenAlex.

  1. Article
  2. Air Change Rate and SARS-CoV-2 Exposure in Hospitals and Residences: A Meta-Analysis.Aerosol science and technology : the journal of the American Association for Aerosol Research · 2024
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4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

10 authors at 3 institutions in 2 countries.

Ashley Styczynski *Division of Infectious Diseases and Geographic Medicine, Stanford University School of Medicine, Stanford, California, USA astyczyn@stanford.edu.ORCID 0000-0002-4682-8087
Caitlin Hemlock *Division of Epidemiology and Biostatistics, University of California Berkeley, Berkeley, California, USA.
Kazi Injamamul Hoque *Laboratory Sciences and Services Division, International Centre for Diarrhoeal Disease Research, Bangladesh, Dhaka, Bangladesh.
Renu Verma *Division of Infectious Diseases and Geographic Medicine, Stanford University School of Medicine, Stanford, California, USA.
Chris LeBoa *Division of Infectious Diseases and Geographic Medicine, Stanford University School of Medicine, Stanford, California, USA.
Md Omar Faruk Bhuiyan *Laboratory Sciences and Services Division, International Centre for Diarrhoeal Disease Research, Bangladesh, Dhaka, Bangladesh.
Auddithio Nag *Division of Infectious Diseases and Geographic Medicine, Stanford University School of Medicine, Stanford, California, USA.
Md Golam Dostogir Harun *Laboratory Sciences and Services Division, International Centre for Diarrhoeal Disease Research, Bangladesh, Dhaka, Bangladesh.
Mohammed Badrul Amin *Laboratory Sciences and Services Division, International Centre for Diarrhoeal Disease Research, Bangladesh, Dhaka, Bangladesh.
Jason R Andrews *Division of Infectious Diseases and Geographic Medicine, Stanford University School of Medicine, Stanford, California, USA.
Stanford University · USInternational Centre for Diarrhoeal Disease Research · BDCancer Research And Biostatistics · US

Funding

Global Epidemiology of Infectious DiseasesT32AI052073 · NIAID · STANFORD UNIVERSITY · PI Angelle Desiree LaBeaud, Stephen Patrick Luby · 2003 to 2026
$4.2M
6 · The paper itself

Abstract

objectivesTo evaluate the risk of exposure to SARS-CoV-2 in naturally ventilated hospital settings by measuring parameters of ventilation and comparing these findings with results of bioaerosol sampling. STUDY

designCross-sectional study. STUDY SETTING AND STUDY SAMPLE: The study sample included nine hospitals in Dhaka, Bangladesh. Ventilation characteristics and air samples were collected from 86 healthcare spaces during October 2020 to February 2021. PRIMARY OUTCOME: Risk of cumulative SARS-CoV-2 infection by type of healthcare area. SECONDARY OUTCOMES: Ventilation rates by healthcare space; risk of airborne detection of SARS-CoV-2 across healthcare spaces; impact of room characteristics on absolute ventilation; SARS-CoV-2 detection by naturally ventilated versus mechanically ventilated spaces.

resultsThe majority (78.7%) of naturally ventilated patient care rooms had ventilation rates that fell short of the recommended ventilation rate of 60 L/s/p. Using a modified Wells-Riley equation and local COVID-19 case numbers, we found that over a 40-hour exposure period, outpatient departments posed the highest median risk for infection (7.7%). SARS-CoV-2 RNA was most frequently detected in air samples from non-COVID wards (50.0%) followed by outpatient departments (42.9%). Naturally ventilated spaces (22.6%) had higher rates of SARS-CoV-2 detection compared with mechanically ventilated spaces (8.3%), though the difference was not statistically significant (p=0.128). In multivariable linear regression with calculated elasticity, open door area and cross-ventilation were found to have a significant impact on ventilation.

conclusionOur findings provide evidence that naturally ventilated healthcare settings may pose a high risk for exposure to SARS-CoV-2, particularly among non-COVID-designated spaces, but improving parameters of ventilation can mitigate this risk.

Indexed as

COVID-19SARS-CoV-2BangladeshCross-Sectional StudiesDelivery of Health CareHumansRNA, ViralVentilationRNA, ViralAirborne transmissionCOVID-19healthcarehospitalnosocomial infectionSARS-CoV-2ventilation

Identifiers

PMID35428628
PMCPMC9013789
OpenAlexW4223895686

What OpenQuestion holds

Textmetadata
LicenceCC BY-NC
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.