Removal of cockroach allergen from inner-city homes

Background: Allergen avoidance has been shown to improve the morbidity and physiology of asthma. Although cockroach allergen has been implicated in chronic asthma, little work has been reported on the feasibility of allergen removal from infested homes. Objective: The objective of this study was to examine the effect of professional pest control and home cleaning on cockroach infestation and allergen concentrations in settled dust samples from the kitchens, bedrooms, and television-living rooms of inner-city homes. Methods: Thirteen homes in inner-city Baltimore, Maryland, received a professional cleaning, with vacuuming and a thorough cleaning in the kitchen. Pest control technicians applied abamectin 0.05% gel to the kitchen and, to a limited extent, to the rest of the home and the cleaning was repeated. Technicians visited monthly from month 2 to month 8 to inspect, collect dust samples, and place passive cockroach traps. Bla g 1 concentrations in dust extract were measured by means of ELISA. Results: The number of cockroaches captured in passive traps decreased rapidly in 11 homes, but complete extermination was achieved in only 7 homes. Bla g 1 concentrations were reduced by 93% in kitchens, 77 % in television-living rooms, and 74% in bedrooms. The relative reduction in cockroach allergen was not related to successful extermination or to signs of poor housecleaning. Conclusion: We concluded that cockroach extermination is feasible in inner-city homes but that standard housecleaning procedures are only partially effective in removing residual allergen over 8 months.