House dust mites and skin tests in different Australian localities

Dermatophagoides mite concentrations in household dust have been measured in three Australian towns with contrasting geographical features, climate, and degree of urbanisation. Mite allergen skin tests on school children living in these areas showed that the prevalence of positive reactions varied with mite concentrations. In Belmont, D. farinae as well as D. pteronyssinus were present in some of the dust samples. Skin test weals were larger in Busselton than in either Wagga Wagga or Belmont. The importance and practical implications of these findings are discussed.