title: Cough aerosol in healthy participants: fundamental knowledge to optimize droplet-spread infectious respiratory disease management.
abstract: BACKGROUND
  The Influenza A H1N1 virus can be transmitted via direct, indirect, and airborne route to non-infected subjects when an infected patient coughs, which expels a number of different sized droplets to the surrounding environment as an aerosol. The objective of the current study was to characterize the human cough aerosol pattern with the aim of developing a standard human cough bioaerosol model for Influenza Pandemic control.
  
  
  METHODS
  45 healthy non-smokers participated in the open bench study by giving their best effort cough. A laser diffraction system was used to obtain accurate, time-dependent, quantitative measurements of the size and number of droplets expelled by the cough aerosol.
  
  
  RESULTS
  Voluntary coughs generated droplets ranging from 0.1 - 900 microns in size. Droplets of less than one-micron size represent 97% of the total number of measured droplets contained in the cough aerosol. Age, sex, weight, height and corporal mass have no statistically significant effect on the aerosol composition in terms of size and number of droplets.
  
  
  CONCLUSIONS
  We have developed a standard human cough aerosol model. We have quantitatively characterized the pattern, size, and number of droplets present in the most important mode of person-to-person transmission of IRD: the cough bioaerosol. Small size droplets (< 1 μm) predominated the total number of droplets expelled when coughing. The cough aerosol is the single source of direct, indirect and/or airborne transmission of respiratory infections like the Influenza A H1N1 virus.
  
  
  METHODS
  Open bench, Observational, Cough, Aerosol study.
authors.affiliation: Mucophysiology Laboratory, Department of Medicine, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB, Canada. g.zayas@ualberta.ca
authors.forename: Gustavo
authors.initials: G
authors.lastname: Zayas
authors.forename: Ming C
authors.initials: MC
authors.lastname: Chiang
authors.forename: Eric
authors.initials: E
authors.lastname: Wong
authors.forename: Fred
authors.initials: F
authors.lastname: MacDonald
authors.forename: Carlos F
authors.initials: CF
authors.lastname: Lange
authors.forename: Ambikaipakan
authors.initials: A
authors.lastname: Senthilselvan
authors.forename: Malcolm
authors.initials: M
authors.lastname: King
mesh_terms: D000328:Adult; D000336:Aerosols; D000704:Analysis of Variance; D003140:Communicable Disease Control; D003371:Cough; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D008962:Models, Theoretical; D010316:Particle Size; D012141:Respiratory Tract Infections / Q000517:prevention & control / Q000635:transmission; D055815:Young Adult
chemical_list: D000336:Aerosols