title: House dust mite allergen levels in carpeted sleeping accommodation are higher in private houses than public places.
abstract: OBJECTIVE
  To compare mite allergen levels in carpeted sleeping accommodation in private dwellings and public places.
  
  
  METHODS
  The concentration of Dermatophagoides pteronyssinus Group 1 allergen in house dust was measured in mat-tresses and bedroom floors in 12 homes, 5 hotels, 11 child care centres and a university hall of residence. Indoor temperature and relative humidity were also measured. A questionnaire clarified details regarding the age of the building, age of the carpet, method and frequency of cleaning, frequency of room use and use of air-conditioning.
  
  
  RESULTS
  Median allergen levels in mattresses and carpets in private homes (21.1 and 20.6 micro g/g dust, respectively) were significantly higher than in public places (2.5 and 3.1 micro g/g, respectively; P < 0.0001). Mean relative humidity was significantly higher in private houses (68.5%; 95% CI 67.2-69.3%) than in public places (56.4%; 95% CI 52.7-60.1%; P < 0.0001).
  
  
  CONCLUSIONS
  Carpeted sleeping accommodation in public places has lower house dust mite allergen levels than private houses. Lower levels of relative humidity may be an important component of the explanation.
authors.affiliation: New South Wales Cervical Screening Program, Westmead Hospital, Australia.
authors.forename: H A
authors.initials: HA
authors.lastname: Mamoon
authors.forename: R L
authors.initials: RL
authors.lastname: Henry
authors.forename: J E
authors.initials: JE
authors.lastname: Stuart
authors.forename: P G
authors.initials: PG
authors.lastname: Gibson
mesh_terms: D000485:Allergens / Q000032:analysis*; D039741:Antigens, Dermatophagoides / Q000032:analysis*; D001513:Beds; D002648:Child; D002656:Child Day Care Centers; D003430:Cross-Sectional Studies; D005430:Floors and Floorcoverings; D006798:Housing; D006801:Humans; D006813:Humidity; D009517:New South Wales; D018709:Statistics, Nonparametric
chemical_list: D000485:Allergens; D039741:Antigens, Dermatophagoides