Evidence map›Paper›PMID 35645452›Full record

ArticleBuilding and environment2022

Airborne transmission of the Delta variant of SARS-CoV-2 in an auditorium.

Jianxiang Huang, Tongping Hao, Xiao Liu, Phil Jones, Cuiyun Ou, Weihui Liang, Fuqiang Liu

Abstract read
In one paragraph

Article in Building and environment, 2022. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 3 papers.

0numbers the graph read from it
0cells of the map it votes in
3citing papers in PubMed
–field-weighted citation impact
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

3 citing papers in PubMed.

  1. Article
  2. Article
  3. Review
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

7 authors.

Jianxiang HuangDepartment of Urban Planning and Design, The University of Hong Kong, Pokfulam Rd, Hong Kong SAR, China.
Tongping HaoDepartment of Urban Planning and Design, The University of Hong Kong, Pokfulam Rd, Hong Kong SAR, China.
Xiao LiuSchool of Architecture, South China University of Technology, Guangzhou, 510641, China.
Phil JonesWelsh School of Architecture, Cardiff University, King Edward VII Avenue, Cardiff, United Kingdom.
Cuiyun OuSchool of Atmospheric Sciences, Sun Yat-sen University, and Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, China.
Weihui LiangSchool of Architecture and Urban Planning, Nanjing University, Nanjing, 210093, China.
Fuqiang LiuOffice of Emergency Response to Public Health Emergencies, Hunan Provincial Center for Disease Control and Prevention, No. 450, Section 1, Furong Middle Road, Kaifu District, Changsha City, Hunan Province, China.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

The Delta variant of SARS-CoV-2 has inflicted heavy burdens on healthcare systems globally, although direct evidence on the quantity of exhaled viral shedding from Delta cases is lacking. The literature remains inconclusive on whether existing public health guidance, based on earlier evidence of COVID-19, should respond differently to more infectious viral strains. This paper describes a study on an outbreak of the Delta variant of COVID-19 in an auditorium, where one person contracted the virus from three asymptomatic index cases sitting in a different row. Field inspections were conducted on the configuration of seating, building and ventilation systems. Numerical simulation was conducted to retrospectively assess the exhaled viral emission, decay, airborne dispersion, with a modified Wells-Riley equation used to calculate the inhalation exposure and disease infection risks at the seat level. Results support the airborne disease transmission. The viral emission rate for Delta cases was estimated at 31 quanta per hour, 30 times higher than those of the original variant. The high quantity of viral plume exhaled by delta cases can create a high risk zone nearby, which, for a mixing ventilation system, cannot be easily mitigated by raising mixing rates or introducing fresh air supply. Such risks can be reduced by wearing an N95 respirator, less so for social distancing. A displacement ventilation system, through which the air is supplied at the floor and returned from the ceiling, can reduce risks compared with a mixing system. The study has implications for ventilation guidelines and hygiene practices in light of more infectious viral strains of COVID-19.

Indexed as

Airborne transmissionAuditoriumCOVID-19Delta variantNumerical simulation

Identifiers

PMID35645452
PMCPMC9128309

What OpenQuestion holds

Textmetadata
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.