the defence of dirt
BMJ 2004; 328 doi: https://doi.org/10.1136/bmj.38075.565822.55 (Published 20 May 2004) Cite this as: BMJ 2004;328:1226All rapid responses
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I was interested in the conclusion of this paper, which suggests that
vaccination to boost T cell responses should be developed to counteract
the increase in allergies produced by lack of exposure to "old friends" in
the bacterial world.
As I understand the hypothesis, it states that increasing
microbiological sterility in our environment produced by constant routine
dousing of our houses and ourselves with antibacterial chemicals in the
name of hygiene, generates an abnormal set of immunological responses
resulting in allergies.
A better response to all this would be for children to be encouraged
to play in the dirt, for us all to use soap in our homes rather than
antibacterial cleanser, and to confine disinfectant to around the toilet
rather than on all available surfaces. Eating live yoghurt might also
help, as might encouraging frequent and regular physical contact with our
pets, for both psychological and immunological reasons.
I would much prefer to live out this sort of existence than be
forever dependent on medical technology to bolster an immune system
fatally weakened by a life long obsession with hygiene and a preoccupation
with maintaining a sterile barrier with the natural world.
Competing interests:
None declared
Competing interests: No competing interests
I believe that you and your readers who are interested in the hygiene
hypothesis will be interested in the article cited below, published
recently in Clin Rev Allergy Immunol
Clinical Reviews in Allergy & Immunology
> Volume 26, Issue 2, April 2004
> Parasite Allergy, Part II
> Table of Contents:
>
> 1. The Role of Parasites in Genetic Susceptibility to
>Allergy: IgE, Helminthic Infection and Allergy, and the Evolution of
>the Human Immune System
> Hagel, Isabel; Di Prisco, Maria Cristina; Goldblatt,
>Jack; Le Souef, Peter N.
> Click here to visit the article online:
>
>http://www.humanapress.com/ArticleDetail.pasp?issn=1080-
0549&acode=CRIAI:26:2:075
>
Respectfully,
David A. Levy, M.D.
Topic Editor for that issue
Competing interests:
None declared
Competing interests: No competing interests
Natural way of life versus dirt!
Dr Watts' article and the two responses made interesting reading.
However, it is possible that it is not cleanliness, but, the ways of
achieving it, is the problem.
The various chemicals that one uses to keep the immediate environment at
home clean and free of pests are possibly responsible for some of the
disorders mentioned. Not to forget the pesticides used in farms.
Being a paediatrician, I must stress on the protective influence of breast
milk to infants. Probably, a late introduction of animal protein into the
infant's diet may also help in preventing some of these disorders.
It is possible that the factors mentioned in the article "large household
size, a poor standard of living, not using antibiotics, and early exposure
to farm animals", may also be promoting a natural way of life. These
families may resort to breast milk rather than formula for their infants.
These households may also lack the resources to spend on pesticides and
chemicals at home. They may be using a simple soap to wash their hands
rather than one with chemicals!
One needs to look deeper before immunology starts having an affair with
dirt!
Competing interests:
None declared
Competing interests: No competing interests