A few days ago I was asked for an opinion on the thesis, put forward recently, that it is a good idea for children to get themselves mucky from time to time because, by doing so, they stimulate their immune system and are less likely to develop asthma in later life.
The immune system is not underdeveloped in asthmatics. If anything the reverse is true. Asthma occurs because of over-reactivity to many substances, such as pollens, dust mite droppings, noxious gases, virus infections, antibiotics and many other materials that are taken into the tissues in the air we breathe or in the foods we eat.
The initial contact with the substance which provokes an allergic attack (the allergen) often occurs in childhood.
It is usual for there to be a significant amount of allergen in the initial contacts and this stimulates the production of antibodies, notably one called IgE, from the mast cells in the lung and in the blood.
Because the IgE is already there, subsequent exposure to minute amounts of antigen (the substance sparking off the allergic reaction) produces an explosive release of chemicals from the white blood cells.
The antigen acts as the detonator. These chemicals, such as histamine, prostaglandins and leucotrienes, cause the muscles of the airways to go into spasm and the airway is further obstructed by the production of thick viscous mucus. Asthma results.
What better method of supplying the initial sensitising stimulus to dust mite protein is there than by letting children play on the carpet? Wool carpets are difficult to keep clean and synthetics become electrostatically attractive to dust.
Dusty farming environments, such the hay loft, and old damp houses where there is fungal infection of the timber, are also well-known locations for producing allergy.
Once the allergy is established minimal subsequent challenge with the same, or a closely similar antigen, will trigger an attack.
Food allergies and reactions to the perfume and actual proteins of plants and flowers are not uncommon. Reaction to pharmaceuticals, such as aspirin and non specific anti-inflammatory agents occur. These may well be blamed on modern living but where is the proof that letting the children get mucky would have prevented their asthmatic tendency?
Children, and for that matter adults, who get their skin contaminated with soil, are likely to come in contact with Clostridium tetani, an organism which survives as spores in previously manured areas.
Cut the skin and into the tissues goes filth and bacteria. The soil alters the oxygen/reduction potential of the tissues and the Clostridium can then become a vegetative organism which produces a very powerful poison.
The victim gets tetanus and dies a horrid death. This is uncommon nowadays because we have tetanus immunisation which is effective. Nevertheless, I have seen two deaths from tetanus.
Sending the children out to play on ground which has been manured by dog shit is taking a risk with their sight.
There are ?old wives?? sayings such as ? a little bit of dirt never hurt anybody? and ?you?ll eat a peck and a half of muck before you die? are things of the past.
Reading through some of the history returns for the beginning of the last century makes interesting reading.
Death in infancy was common. Only the fittest, the luckiest or those with the optimal genetic make-up survived.
Typhoid fever, cholera, measles, whooping cough, smallpox, rheumatic fever and diphtheria have all been controlled by modern hygiene and immunization – and not by the development of natural immunity.
I would rather immunise my grandchildren than rely on some loony idea that frequent exposure to minor risks of infection by natural exposure will keep them healthy.
The present day increase in the amount of asthma is due to present-day allergens and not to the absence of minimal exposure to multiple immune system challenges some time way back in our childhood.