Biological aspects of the house dust mite (dermataphagoides pteronyssinus) in relation to house dust atopy

To examine the validity of the old idea of the possible significance of mites for house dust atopy it was necessary to study the mite fauna of house dust. The most important findings in this investigation are that mites occur regularly, rather than occasionally, in house dust, and that the mite genus Dermatophagoides is represented by much higher numbers than any of the other genera found in dust.

Furthermore, it appears that there is a seasonal periodicity in the numbers of mites in dust with a maximum from August to October, and also that the numbers of mites in the dust from various houses differ considerably. House dust from high-mountain areas contains very few mites.

These observations fit very well with the knowledge of the seasonal and topographical variations in the allergen content of various dust samples.

Based on laboratory observations on the temperature and humidity requirements of Dermatophagoides, a model is constructed which makes the relation between the degree of dampness of houses and the numbers of mites in the dust understandable.

In this paper only very short mention is made of the many experiments showing the identity between the house dust allergen and the allergen produced by Dermatophagoides.

From the comparison of skin reactions to equivalent extracts of different species of mites it appears that the allergenic products of mites of one family tend to be identical.