The prevalence of mouse allergen in inner-city homes.

Mouse allergen has not been studied in detail in the general population. It is common for patients from inner-city environments to report significant mouse infestation in their homes and neighborhoods. The aim of this study was to determine the prevalence of mouse allergen in the homes of inner-city children with asthma in relation to the demographic features of these children and their specific housing characteristics. Seventy-eight dust samples from 39 inner-city homes of Lodz, Poland, were analyzed for mouse allergen. Skin-prick tests (SPTs) to mouse allergen were performed in all patients. In addition, data regarding the demographics and housing of the subjects were related to the mouse allergen levels. Mouse allergen was detected in 22 of 78 dust samples (28%), and in 18 of 39 homes (46%), including 13 kitchen (33%) and nine bedroom (23%) samples. Mouse allergen levels did not correlate between different rooms in the same home. The levels detected ranged from 0.09 to 2.34 micro g/g of dust. The highest levels were found in kitchens, with median levels of 0.2 micro g/g, 95% confidence interval (CI): 0.12-0.85 (range: 0.1-2.34 microg/g); in bedrooms the mean levels were 0.23 microg/g, 95% CI: 0.1-0.97 (range: 0.09-1.62 microg/g). Eleven of 18 children with detectable mouse allergen in house dust, and three of 21 without detectable mouse allergen in house dust, had a positive SPT to mouse allergen. On home inspection, 18% of the homes had evidence of mice in one or two rooms and had higher levels of mouse allergen (p < 0.01). None of the other subject or housing variables evaluated were associated with higher mouse allergen levels. In Polish children, mouse allergen is an important factor of sensitivity and should be recognized in the diagnosis of allergic diseases as well as in allergen-reduction programmes.