Cockroach Allergens and Testing

One indoor allergen that most do not think about is the cockroach allergen. According to The Asthma and Allergy Foundation of America (AAFA), cockroach allergens were first reported in 1943 and confirmed as a skin allergy in 1959. The cockroach allergen comes from feces and saliva of cockroaches, as well as from pieces of a cockroach’s body.

According to the AAFA, 78-98% of urban homes have cockroaches. A recent study conducted by the National Institute of Environmental Health Sciences (NIEHS) has concluded that cockroach allergens have a direct effect on asthma and allergies of children. The study was conducted with the participation of 900 children who lived in the inner city of seven U.S. cities. The children in this group had suffered some sort of asthma-related hospitalization or emergency room visit in the six months prior to registration for the study, and had been tested positive for any of eleven indoor allergens, including mold, cockroach, dust mite, cat, dog, or rodent allergens. Evaluations and questionnaires were administered to participants to identify any symptoms that they were experiencing, as well as any allergy tests that had been performed on them and medication that they had used. Inspections were conducted to collect dust samples of the participants’ sleeping quarters to test for the specific allergens.

Those children studied that had moderate to severe cockroach allergies had more unscheduled doctor visits and missed more days of school than those that had other types of allergies. It was additionally found that the type of housing and location influenced what types of allergens were found in those locations. For example, more dust mites were found in houses and more cockroaches were found in apartment buildings.

The most common species of cockroaches found in the U.S. are German, American, and Oriental cockroaches. However, the Bla g 1 allergen of the German cockroach is the only test currently available in commercial laboratories and there may be or not be cross reactivity among the different species. Therefore, receiving negative results for the Bla g 1 allergen does not necessarily mean that the environment is free of other cockroach allergens. Investigators should also look for other indicators, such as the actual sighting of cockroaches and the presence of cockroach feces and egg sacs.

Reducing exposure to cockroaches can minimize cockroach allergens. Preventative measures recommended by Dr. Rebecca Gruchalla, chief of allergy and immunology at University of Texas Southwestern, include eating only in the kitchen or eating areas, taking garbage out daily, fixing leaky faucets, cleaning countertops and floors regularly and storing shelf-stable food in sealable bags or plastic containers.

Dust samples can be analyzed for cockroach allergens at American Environmental Labs as an individual analysis or as part of our full allergen screen which could include dog, cat, and dust mite allergens. Please contact AEL at 314-664-2800.