Bacterial and fungal agents in house dust and wheeze in children: the PARSIFAL study

Clin Exp Allergy. 2005 Oct;35(10):1272-8. doi: 10.1111/j.1365-2222.2005.02339.x.


Background: Growing up on a farm and an anthroposophic lifestyle are associated with a lower prevalence of allergic diseases in childhood. This might be related to increased inhalatory exposure to microbial agents.

Objective: To assess the association between microbial agents in house dust and atopic wheeze in farm children, Steiner school children and reference children.

Methods: Levels of bacterial endotoxin, fungal beta(1,3)-glucans and fungal extracellular polysaccharides (EPS) in mattress and living room floor dust were measured in a population of 270 atopic (=Phadiatop-positive) children with self-reported wheezing, including 168 current atopic wheezers, and 441 non-atopic, non-symptomatic controls. These children were selected from a cross-sectional study in five European countries.

Results: In the study population as a whole, average levels of mattress dust endotoxin, EPS and glucans were slightly (1.1-1.2-fold; P<0.10) higher in control children than in atopic wheezers. Atopic wheeze was related to mattress levels of endotoxin, EPS and glucans in farm and farm-reference children. However, when adjusting for group (farm vs. farm-reference children), the associations became non-significant whereas the group effect remained. No associations between atopic wheeze and microbial agents were observed in Steiner and Steiner-reference children. For current atopic wheeze, the farm effect became non-significant after adjustment for microbial agent levels.

Conclusion: Not only bacterial endotoxin but also mould components might offer some protection against atopic wheeze in children. However, the protective effect of being raised on a farm was largely unexplained by the mattress microbial agent levels measured in this study.

Publication types

  • Multicenter Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Agriculture*
  • Air Pollution, Indoor / analysis
  • Allergens / analysis*
  • Antigens, Fungal / analysis
  • Beds
  • Child
  • Child, Preschool
  • Cross-Sectional Studies
  • Dust / analysis*
  • Endotoxins / analysis
  • Europe / epidemiology
  • Female
  • Housing
  • Humans
  • Inhalation Exposure / analysis
  • Male
  • Polysaccharides / analysis
  • Respiratory Hypersensitivity / epidemiology
  • Respiratory Hypersensitivity / etiology
  • Respiratory Hypersensitivity / prevention & control*
  • Respiratory Sounds / etiology*
  • Schools
  • beta-Glucans / analysis


  • Allergens
  • Antigens, Fungal
  • Dust
  • Endotoxins
  • Polysaccharides
  • beta-Glucans
  • beta-1,3-glucan