EVALUATION OF GERMAN-COCKROACH (ORTHOPTERA, BLATTELLIDAE) ALLERGEN AND SEASONAL-VARIATION IN LOW-INCOME HOUSING

Six apartments in a low-income housing project were evaluated for Germ an cockroach, Blattella germanica (L.), infestation and concentration of an allergen derived from these cockroaches (Bla g II). Kitchen and living room samples were collected monthly for 1 yr. In addition, airb orne sampling was carried out in 5 kitchens. The kitchen had the highe st allergen concentration in 65% of visits and the highest number of c ockroaches trapped in 69% of visits. In the kitchen, the highest cockr oach levels were seen in June, whereas the values for Bla g II peaked in August. In keeping with this, the closest correlation was between B la g II (mu g/g dust) and the number of cockroaches found 2 mo earlier . Airborne samples were assayed for 2 separate allergens, Bla g II and Bla g I. No allergen was detectable in the absence of disturbance. By contrast, during disturbance with a vacuum cleaner both Bla g II and Bla g I were detectable in the air of each apartment. Results suggest that immunochemical assay of a major allergen in dust samples from the kitchen floor may be used to monitor exposure to German cockroaches, also that cockroach levels may be used as an indicator or predictor of allergen in dust.