The hygiene hypothesis and implications for home hygiene

The “Hygiene Hypothesis” contends that if we are not exposed to infectious agents, the immune system becomes imbalanced, thereby increasing susceptibility to allergic diseases. The report reviews the nature and extent of the link between microbial exposure and the development of the immune system; it also assesses the implications it might have for hygiene, and how the problems presented by the hypothesis might be addressed. This document has been prepared as a special project by the IFH. The document was prepared by Professor Bloomfield and Dr Stanwell Smith. The report was peer reviewed by Professor Stephen Holgate, University of Southampton School of Medicine.