The hygiene hypothesis in allergy and asthma: an update

@article{Brooks2013TheHH,
  title={The hygiene hypothesis in allergy and asthma: an update},
  author={Collin Brooks and Neil Pearce and Jeroen Douwes},
  journal={Current Opinion in Allergy and Clinical Immunology},
  year={2013},
  volume={13},
  pages={70–77}
}
Purpose of reviewIt has been hypothesized that increased cleanliness, reduced family size, and subsequent decreased microbial exposure could explain the increases in global asthma prevalence. This review considers the recent evidence for and against the ‘hygiene hypothesis’. Recent findingsRecent evidence does not provide unequivocal support for the hygiene hypothesis: the hygiene hypothesis specifically relates to atopic asthma, but some of the protective effects (e.g. farm exposures) appear… 
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