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Western Cold and Flu (WeCoF) aerosol study--preliminary results.

Savory E, Lin WE, Blackman K, Roberto MC, Cuthbertson LR, Scott JA, Mubareka S - BMC Res Notes (2014)

Bottom Line: The peak value of velocity was also extracted and compared with the average velocity.Preliminary results show that there is significant air motion associated with a cough (on the order of 0.5 m/s) as far away as 1 m from the mouth of the healthy person who coughs.The results from this pilot study provide the framework for a more extensive participant recruitment campaign that will encompass a statistically-significant cohort.

View Article: PubMed Central - PubMed

Affiliation: Department of Mechanical & Materials Engineering, The University of Western Ontario, 1151 Richmond Street North, London N6A 5B9, Canada. wlin26@uwo.ca.

ABSTRACT

Background: Influenza virus is responsible for annual deaths due to seasonal epidemics and is the cause of major pandemics which have claimed millions of human lives over the last century. Knowledge about respiratory virus transmission is advancing. Spread is likely through the air, but much work remains to be done to characterize the aerosols produced by infected individuals, including viral particle survival and infectivity. Although coughs have been characterized, little work has been done to examine coughs from infected individuals. The WeCoF project aims at providing evidence to support prevention measures to mitigate person-to-person influenza transmission in critical locations, such as hospitals, and during pandemics.

Findings: A novel experimental cough chamber facility - the FLUGIE - has been developed to study the far-field aerodynamics and aerosol transport of droplets produced by the coughs from humans naturally-infected with influenza. The flow field of each cough is measured using Particle Image Velocimetry (PIV). A preliminary study involving 12 healthy individuals has been carried out in order to quantify the strengths of their coughs at a distance of 1 m from the mouth. The spatially averaged maximum velocity was determined and the average value was 0.41 m/s across 27 coughs of good data quality. The peak value of velocity was also extracted and compared with the average velocity.

Conclusions: Preliminary results show that there is significant air motion associated with a cough (on the order of 0.5 m/s) as far away as 1 m from the mouth of the healthy person who coughs. The results from this pilot study provide the framework for a more extensive participant recruitment campaign that will encompass a statistically-significant cohort.

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Related in: MedlinePlus

Diagrammatic layout of the 2 m × 2 m × 2 m FLUGIE cough chamber (all dimensions shown in metres).
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Fig1: Diagrammatic layout of the 2 m × 2 m × 2 m FLUGIE cough chamber (all dimensions shown in metres).

Mentions: A novel experimental facility (the FLUGIE cough chamber) has been constructed at Western and protocols developed for its use. Biosafety and research ethics approvals have been obtained for studies involving human participants who are naturally-infected with pathogens such as influenza virus. Figure 1 shows a diagrammatic layout of the facility for PIV measurements, with the subject seated outside the chamber. Since the entrainment of ambient air into the cough jet is important to the development of that jet, a solid barrier with only a small opening for the mouth (such as the 5 × 3 cm hole used by[51]) is inappropriate. In the FLUGIE, the opening is pear-shaped such that the participant’s nose and mouth area are unobstructed whilst a cough is directed into the enclosed test chamber. The major vertical axis of the pear-shaped opening is 15 cm high and the base of the opening, where the participant’s chin rests, is 67 cm above the chamber floor. The minor horizontal axis of the pear-shaped opening is 10.5 cm wide. This chamber inlet has a cover, which is only opened when a cough is introduced into the chamber.Figure 1


Western Cold and Flu (WeCoF) aerosol study--preliminary results.

Savory E, Lin WE, Blackman K, Roberto MC, Cuthbertson LR, Scott JA, Mubareka S - BMC Res Notes (2014)

Diagrammatic layout of the 2 m × 2 m × 2 m FLUGIE cough chamber (all dimensions shown in metres).
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC4150972&req=5

Fig1: Diagrammatic layout of the 2 m × 2 m × 2 m FLUGIE cough chamber (all dimensions shown in metres).
Mentions: A novel experimental facility (the FLUGIE cough chamber) has been constructed at Western and protocols developed for its use. Biosafety and research ethics approvals have been obtained for studies involving human participants who are naturally-infected with pathogens such as influenza virus. Figure 1 shows a diagrammatic layout of the facility for PIV measurements, with the subject seated outside the chamber. Since the entrainment of ambient air into the cough jet is important to the development of that jet, a solid barrier with only a small opening for the mouth (such as the 5 × 3 cm hole used by[51]) is inappropriate. In the FLUGIE, the opening is pear-shaped such that the participant’s nose and mouth area are unobstructed whilst a cough is directed into the enclosed test chamber. The major vertical axis of the pear-shaped opening is 15 cm high and the base of the opening, where the participant’s chin rests, is 67 cm above the chamber floor. The minor horizontal axis of the pear-shaped opening is 10.5 cm wide. This chamber inlet has a cover, which is only opened when a cough is introduced into the chamber.Figure 1

Bottom Line: The peak value of velocity was also extracted and compared with the average velocity.Preliminary results show that there is significant air motion associated with a cough (on the order of 0.5 m/s) as far away as 1 m from the mouth of the healthy person who coughs.The results from this pilot study provide the framework for a more extensive participant recruitment campaign that will encompass a statistically-significant cohort.

View Article: PubMed Central - PubMed

Affiliation: Department of Mechanical & Materials Engineering, The University of Western Ontario, 1151 Richmond Street North, London N6A 5B9, Canada. wlin26@uwo.ca.

ABSTRACT

Background: Influenza virus is responsible for annual deaths due to seasonal epidemics and is the cause of major pandemics which have claimed millions of human lives over the last century. Knowledge about respiratory virus transmission is advancing. Spread is likely through the air, but much work remains to be done to characterize the aerosols produced by infected individuals, including viral particle survival and infectivity. Although coughs have been characterized, little work has been done to examine coughs from infected individuals. The WeCoF project aims at providing evidence to support prevention measures to mitigate person-to-person influenza transmission in critical locations, such as hospitals, and during pandemics.

Findings: A novel experimental cough chamber facility - the FLUGIE - has been developed to study the far-field aerodynamics and aerosol transport of droplets produced by the coughs from humans naturally-infected with influenza. The flow field of each cough is measured using Particle Image Velocimetry (PIV). A preliminary study involving 12 healthy individuals has been carried out in order to quantify the strengths of their coughs at a distance of 1 m from the mouth. The spatially averaged maximum velocity was determined and the average value was 0.41 m/s across 27 coughs of good data quality. The peak value of velocity was also extracted and compared with the average velocity.

Conclusions: Preliminary results show that there is significant air motion associated with a cough (on the order of 0.5 m/s) as far away as 1 m from the mouth of the healthy person who coughs. The results from this pilot study provide the framework for a more extensive participant recruitment campaign that will encompass a statistically-significant cohort.

Show MeSH
Related in: MedlinePlus