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Wise et al.

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IX.A.2. Cockroach— Cockroach infestation and allergen concentrations are often high in multi-occupant dwellings in densely populated inner city areas; although elevated levels of cockroach allergen are also found in homes in warmer, rural regions. 1129-1131 Interventions are targeted at eliminating infestations and abating cockroach allergen in homes. A systematic review by Le Cann et al., 1132 identified 3 key strategies for home environmental interventions: (1) education-based methods that included instruction on house cleaning measures and sealing cracks and crevices in areas where infestation occurs (ie, kitchens); (2) physical methods using insecticides or bait traps; and (3) combination therapy containing both educational-based interventions and physical methods (Table IX.A.2). Most studies included 1 or more interventions aimed at reducing cockroach counts and allergen (Bla g 1 and Bla g 2) levels 1133-1140 ; however, a few focused on eliminating multiple allergens (eg, HDM, cockroach, rodent, cat, dog). 1141,1142 The most effective treatment for eliminating infestation and reducing allergen load was professional pest control. 1135 Sever et al. 1133 found placement of insecticide bait traps to be more effective in reducing cockroach populations with a concomitant reduction in cockroach allergen compared to homes that received applications of insecticide formulations to baseboards, cracks, and crevices monitored over a 12-month period. When cost was considered, the price of bait traps along with labor and monitoring costs were found to be less expensive than multiple commercial applications of insecticide sprays to baseboards and cracks. 1133 As the expense of integrated home management consisting of professional cleaning, education, and pest control is not economically sustainable, investigations are focused on assessing the efficacy of single interventions, such as extermination alone, to assess possible cost benefits. 1135,1143 In addition, family adherence to home-based interventions was generally poor, resulting in elevated cockroach concentrations over time. 1138 Although there are a substantial number of RCTs that evaluated the efficacy of specific environmental control measures to eliminate the number of cockroaches and reduce cockroach allergen level, respiratory health outcomes were rarely measured. Even though cockroach count and Bla g1 and Bla g2 allergen levels were reduced in many studies with home interventions, the level of cockroach allergen following treatment remained higher than acceptable median levels associated with clinical benefits in sensitized individuals. 1134,1137-1140 Although cockroach count could be significantly reduced in single-family homes using bait traps, re-infestation and high allergen levels remained an ongoing problem in multifamily buildings. 1140 Thus it is difficult to dramatically reduce cockroach allergen levels in the home unless a significant reduction in cockroach counts is maintained over time. 1133 Most studies did not include clinical endpoints; however, those that did evaluate clinical outcomes focused on asthma symptoms, hospitalizations or emergency room visits, and medication usage. 1141,1142 No studies included any assessment of symptoms associated with AR or its treatment. • Aggregate Grade of Evidence: B (Level 1a: 1 study; Level 1b: 8 studies; Level 2b: 1 study; Level 3b: 1 study; Table IX.A.2).

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Int Forum Allergy Rhinol . Author manuscript; available in PMC 2020 June 10.