title: Staphylococcus aureus dispersal from healthy volunteers.
abstract: BACKGROUND
  Understanding Staphylococcus aureus dispersal from human carriers is vital for preventing transmission and colonization of this organism in health care settings. This study investigated the S aureus supershedder hypothesis in relation to attributes of healthy volunteers.
  
  
  METHODS
  Microbial aerosol generation from volunteers was quantified within a controlled environmental chamber during walking or sitting activities. Biological air samplers were used to determine numbers of total S aureus colony-forming units disseminated during these activities.
  
  
  RESULTS
  A total of 17 volunteers was sampled on 3 occasions. Hairstyle (long hair tied up or a shaved head) was the only significant predictor of dissemination of S aureus (5% significance level). No other significant effects were found at the 5% level. A negative binomial distribution provides the best fit with respect to S aureus.
  
  
  CONCLUSIONS
  We found that, in the context of our small sample size, hairstyle (long hair tied up or a shaved head) statistically affected levels of bacteria shed from volunteers. However, we found no evidence for "supershedders" or "cloud adults," suggesting they are at an extreme end of a continuous distribution.
authors.affiliation: Biosafety Investigation Unit, Public Health England, Porton Down, Wiltshire, United Kingdom. Electronic address: Katy-Anne.Thompson@phe.gov.uk.
authors.forename: Katy-Anne
authors.initials: KA
authors.lastname: Thompson
authors.affiliation: Southampton Health Technology Assessments Centre (SHTAC), University of Southampton, Southampton, United Kingdom.
authors.forename: Vicky R
authors.initials: VR
authors.lastname: Copley
authors.affiliation: Biosafety Investigation Unit, Public Health England, Porton Down, Wiltshire, United Kingdom.
authors.forename: Simon
authors.initials: S
authors.lastname: Parks
authors.affiliation: Biosafety Investigation Unit, Public Health England, Porton Down, Wiltshire, United Kingdom.
authors.forename: James T
authors.initials: JT
authors.lastname: Walker
authors.affiliation: Biosafety Investigation Unit, Public Health England, Porton Down, Wiltshire, United Kingdom.
authors.forename: Allan M
authors.initials: AM
authors.lastname: Bennett
mesh_terms: D000293:Adolescent; D000328:Adult; D000336:Aerosols; D002353:Carrier State / Q000453:epidemiology* / Q000382:microbiology; D005260:Female; D050456:Fomites / Q000382:microbiology*; D064368:Healthy Volunteers; D006801:Humans; D008297:Male; D008875:Middle Aged; D013203:Staphylococcal Infections / Q000453:epidemiology* / Q000382:microbiology; D013211:Staphylococcus aureus / Q000302:isolation & purification*; D055815:Young Adult
chemical_list: D000336:Aerosols
keywords: Andersen; MRSA; Sartorius; Visitor