title: Mattress encasings and mite allergen levels in the Prevention and Incidence of Asthma and Mite Allergy study.
abstract: BACKGROUND
  Reduction of allergen exposure from birth may reduce sensitization and subsequent allergic disease.
  
  
  OBJECTIVE
  To measure the influence of mite allergen-impermeable mattress encasings and cotton placebo encasings on the amount of dust and mite allergen in beds.
  
  
  METHODS
  A total of 810 children with allergic mothers took part in the Prevention and Incidence of Asthma and Mite Allergy (PIAMA) study. Allergen-impermeable and placebo mattress encasings were applied to the childrens' and the parents' beds before birth. Dust samples were taken from the beds of children and their parents before birth and 3 and 12 months after birth. Extracts of dust samples were analysed for mite allergens (Der p 1 and Der f 1).
  
  
  RESULTS
  Active mattress encasings were significantly more effective in reducing dust and mite allergen levels than placebo encasings. Mite allergen levels were low in general and the treatment effect was modest. Twelve months after birth, mattresses with active mattress encasings had about half the amount of Der 1 (Der p 1 + Der f 1)/m2, compared to mattresses with placebo encasings, for the child's and the parental mattress.
  
  
  CONCLUSIONS
  This study shows that mite-impermeable mattress encasings have a significant but modest effect on dust and mite allergen levels of mattresses with low initial mite allergen levels, compared to placebo.
authors.affiliation: Department of Environmental and Occupational Health, Institute for Risk Assessment Sciences, Utrecht, the Netherlands.
authors.forename: R T
authors.initials: RT
authors.lastname: van Strien
authors.forename: L P
authors.initials: LP
authors.lastname: Koopman
authors.forename: M
authors.initials: M
authors.lastname: Kerkhof
authors.forename: M
authors.initials: M
authors.lastname: Oldenwening
authors.forename: J C
authors.initials: JC
authors.lastname: de Jongste
authors.forename: J
authors.initials: J
authors.lastname: Gerritsen
authors.forename: H J
authors.initials: HJ
authors.lastname: Neijens
authors.forename: R C
authors.initials: RC
authors.lastname: Aalberse
authors.forename: H A
authors.initials: HA
authors.lastname: Smit
authors.forename: B
authors.initials: B
authors.lastname: Brunekreef
mesh_terms: D000485:Allergens / Q000276:immunology*; D000818:Animals; D039741:Antigens, Dermatophagoides / Q000032:analysis; D060829:Arthropod Proteins; D001512:Bedding and Linens; D001513:Beds; D003546:Cysteine Endopeptidases; D004781:Environmental Exposure; D006801:Humans; D006967:Hypersensitivity / Q000276:immunology / Q000517:prevention & control*; D007223:Infant; D007231:Infant, Newborn; D008925:Mites; D011446:Prospective Studies; D018709:Statistics, Nonparametric
chemical_list: D000485:Allergens; D039741:Antigens, Dermatophagoides; D060829:Arthropod Proteins; D003546:Cysteine Endopeptidases; C451159:Dermatophagoides farinae antigen f 1; C451162:Dermatophagoides pteronyssinus antigen p 1