title: Effect of human movement on airborne disease transmission in an airplane cabin: study using numerical modeling and quantitative risk analysis.
abstract: BACKGROUND
  Airborne transmission of respiratory infectious disease in indoor environment (e.g. airplane cabin, conference room, hospital, isolated room and inpatient ward) may cause outbreaks of infectious diseases, which may lead to many infection cases and significantly influences on the public health. This issue has received more and more attentions from academics. This work investigates the influence of human movement on the airborne transmission of respiratory infectious diseases in an airplane cabin by using an accurate human model in numerical simulation and comparing the influences of different human movement behaviors on disease transmission.
  
  
  METHODS
  The Eulerian-Lagrangian approach is adopted to simulate the dispersion and deposition of the expiratory aerosols. The dose-response model is used to assess the infection risks of the occupants. The likelihood analysis is performed as a hypothesis test on the input parameters and different human movement pattern assumptions. An in-flight SARS outbreak case is used for investigation. A moving person with different moving speeds is simulated to represent the movement behaviors. A digital human model was used to represent the detailed profile of the occupants, which was obtained by scanning a real thermal manikin using the 3D laser scanning system.
  
  
  RESULTS
  The analysis results indicate that human movement can strengthen the downward transport of the aerosols, significantly reduce the overall deposition and removal rate of the suspended aerosols and increase the average infection risk in the cabin. The likelihood estimation result shows that the risk assessment results better fit the outcome of the outbreak case when the movements of the seated passengers are considered. The intake fraction of the moving person is significantly higher than most of the seated passengers.
  
  
  CONCLUSIONS
  The infection risk distribution in the airplane cabin highly depends on the movement behaviors of the passengers and the index patient. The walking activities of the crew members and the seated passengers can significantly increase their personal infection risks. Taking the influence of the movement of the seated passengers and the index patient into consideration is necessary and important. For future studies, investigations on the behaviors characteristics of the passengers during flight will be useful and helpful for infection control.
authors.forename: Zhuyang
authors.initials: Z
authors.lastname: Han
authors.forename: Gin Nam Sze
authors.initials: GN
authors.lastname: To
authors.forename: Sau Chung
authors.initials: SC
authors.lastname: Fu
authors.forename: Christopher Yu-Hang
authors.initials: CY
authors.lastname: Chao
authors.affiliation: Institute of Public Safety Research, Department of Engineering Physics, Tsinghua University, Beijing 100084, China. wgweng@tsinghua.edu.cn.
authors.forename: Wenguo
authors.initials: W
authors.lastname: Weng
authors.forename: Quanyi
authors.initials: Q
authors.lastname: Huang
mesh_terms: D000336:Aerosols / Q000032:analysis*; D000401:Aircraft; D003141:Communicable Diseases / Q000453:epidemiology / Q000635:transmission*; D003198:Computer Simulation; D005069:Evaluation Studies as Topic; D006802:Human Activities; D006801:Humans; D016013:Likelihood Functions; D008962:Models, Theoretical; D018570:Risk Assessment; D014195:Travel
chemical_list: D000336:Aerosols
references.citation: J Occup Environ Hyg. 2005 Mar;2(3):143-54
references.pmid: 15764538
references.citation: J Hyg (Lond). 1946 Sep;44(6):471-9
references.pmid: 20475760
references.citation: Indoor Air. 2002 Sep;12(3):147-64
references.pmid: 12244745
references.citation: J Virol. 2004 Apr;78(7):3572-7
references.pmid: 15016880
references.citation: Am Rev Respir Dis. 1962 Jan;85:33-9
references.pmid: 14480798
references.citation: N Engl J Med. 2003 Dec 18;349(25):2416-22
references.pmid: 14681507
references.citation: Lancet. 2005 Mar 12-18;365(9463):989-96
references.pmid: 15767002
references.citation: Annu Rev Public Health. 2003;24:133-51
references.pmid: 12428033
references.citation: Build Environ. 2007 Sep;42(9):3194-3209
references.pmid: 32287999
references.citation: Build Environ. 2006 Sep;41(9):1214-1222
references.pmid: 32287998
references.citation: Indoor Air. 2006 Oct;16(5):356-72
references.pmid: 16948712
references.citation: J Virol. 2005 Dec;79(24):15511-24
references.pmid: 16306622
references.citation: Indoor Air. 2006 Aug;16(4):296-312
references.pmid: 16842610
references.citation: Indoor Air. 2008 Oct;18(5):425-38
references.pmid: 18691266
references.citation: J Aerosol Sci. 2009 Feb;40(2):122-133
references.pmid: 32287373
references.citation: Environ Sci Technol. 2002 May 1;36(9):207A-211A
references.pmid: 12026996
references.citation: Indoor Air. 2012 Feb;22(1):77-87
references.pmid: 21906177
references.citation: Am J Epidemiol. 1979 Jul;110(1):1-6
references.pmid: 463858
references.citation: Med Microbiol Immunol. 2005 Jan;194(1-2):1-6
references.pmid: 15118911
references.citation: Indoor Air. 2008 Jun;18(3):233-49
references.pmid: 18422965
references.citation: Am Rev Respir Dis. 1967 Dec;96(6):1137-43
references.pmid: 6057616
references.citation: Risk Anal. 2011 Mar;31(3):351-69
references.pmid: 21039710
references.citation: PLoS Pathog. 2013 Mar;9(3):e1003205
references.pmid: 23505369
references.citation: N Engl J Med. 1996 Apr 11;334(15):933-8
references.pmid: 8596593
references.citation: Indoor Air. 2010 Feb;20(1):2-16
references.pmid: 19874402
references.citation: J R Soc Interface. 2013 Sep 11;10(88):20130560
references.pmid: 24026469
references.citation: Jpn J Vet Res. 2004 Nov;52(3):105-12
references.pmid: 15631008
references.citation: Indoor Air. 2011 Feb;21(1):3-11
references.pmid: 21208287
references.citation: Virus Res. 2008 Apr;133(1):33-44
references.pmid: 17451829
references.citation: Nature. 2004 Apr 1;428(6982):561-4
references.pmid: 15024391