title: Inhaling to mitigate exhaled bioaerosols.
abstract: Humans commonly exhale aerosols comprised of small droplets of airway-lining fluid during normal breathing. These "exhaled bioaerosols" may carry airborne pathogens and thereby magnify the spread of certain infectious diseases, such as influenza, tuberculosis, and severe acute respiratory syndrome. We hypothesize that, by altering lung airway surface properties through an inhaled nontoxic aerosol, we might substantially diminish the number of exhaled bioaerosol droplets and thereby provide a simple means to potentially mitigate the spread of airborne infectious disease independently of the identity of the airborne pathogen or the nature of any specific therapy. We find that some normal human subjects expire many more bioaerosol particles than other individuals during quiet breathing and therefore bear the burden of production of exhaled bioaerosols. Administering nebulized isotonic saline to these "high-producer" individuals diminishes the number of exhaled bioaerosol particles expired by 72.10 +/- 8.19% for up to 6 h. In vitro and in vivo experiments with saline and surfactants suggest that the mechanism of action of the nebulized saline relates to modification of the physical properties of the airway-lining fluid, notably surface tension.
authors.affiliation: Harvard University, 322 Pierce Hall, 29 Oxford Street, Cambridge, MA 02138, USA. dedwards@deas.harvard.edu
authors.forename: David A
authors.initials: DA
authors.lastname: Edwards
authors.forename: Jonathan C
authors.initials: JC
authors.lastname: Man
authors.forename: Peter
authors.initials: P
authors.lastname: Brand
authors.forename: Jeffrey P
authors.initials: JP
authors.lastname: Katstra
authors.forename: K
authors.initials: K
authors.lastname: Sommerer
authors.forename: Howard A
authors.initials: HA
authors.lastname: Stone
authors.forename: Edward
authors.initials: E
authors.lastname: Nardell
authors.forename: Gerhard
authors.initials: G
authors.lastname: Scheuch
mesh_terms: D000280:Administration, Inhalation; D000336:Aerosols / Q000032:analysis* / Q000378:metabolism; D003140:Communicable Disease Control / Q000379:methods; D003141:Communicable Diseases / Q000382:microbiology / Q000635:transmission; D045853:Exhalation / Q000187:drug effects / Q000502:physiology*; D006801:Humans; D007552:Isotonic Solutions / Q000008:administration & dosage / Q000494:pharmacology; D009330:Nebulizers and Vaporizers; D010316:Particle Size; D012965:Sodium Chloride / Q000008:administration & dosage* / Q000494:pharmacology*; D013500:Surface Tension / Q000187:drug effects; D014783:Viscosity / Q000187:drug effects
chemical_list: D000336:Aerosols; D007552:Isotonic Solutions; D012965:Sodium Chloride