A study of the ecology of the house dust mite in dwelling houses.

The habitat of dust mites in dwelling houses in Japan was studied to determine the relation between mites in dust and mite allergy. Dust mites increased in the summer and decreased in the winter. Mite propagation was influenced by the temperature and relative humidity. Mites were found in higher concentrations in dust from concrete houses than that from wooden houses. Carpet dust contained numerous mites and tatami, sofas and bed mattresses were also habitats of mites. Mites existed universally in all samples of dust examined. Sensitization to mite allergen depends mainly on the atopic diathesis of patients and not on the mite count.