ACAROSAN AND THE ACAREX TEST IN THE CONTROL OF HOUSE-DUST MITE ALLERGENS IN THE HOME

House dust mites are believed to be major triggers for allergic diseas e in atopic individuals. As part of a programme controlling dietary an d aero-allergen exposure in high-risk infants, an acaricidal foam and powder (Acarosan) was applied to bedroom and main living room carpets, as well as upholstered furniture, on four occasions in the first year of life. Dust was assayed for mite antigen (Der p1) and these results compared with the semi-quantitative assay of guanine content (Acarex Test). After nine months mean Der p1 levels had decreased by 70% in th e treatment group. Proportionally, the greatest fall occurred in those items that had the highest initial mite antigen content. The Acarex s core does show a correlation with Der p1 levels, but cannot replace an tigen assay when accurate data is required. A chemical acaricide may h elp reduce house dust mite antigen levels, but is not by itself suffic ient to reduce levels below that considered critical for sensitisation .