My 4-year old daughter has serious asthma problems that her doctor said could be from cockroaches. Is that possible? We live in an apartment building that has had cockroach problems in the past. We had some roaches when we first moved in a year ago but I haven’t seen any for months. L .P., Southborough, MA

Unfortunately, yes, cockroaches have been implicated in asthma in children, particularly inner-city children. Studies have shown that for inner-city children, German cockroaches are more likely to trigger asthma than pets or dust mites, and the results are more severe. Asthmatic children that are allergic to cockroaches are three times more likely to be hospitalized than are other asthmatic children. Also, a nationwide study found that children living in high-rise apartments in Northeastern U.S. inner cities were the most likely to be affected. It’s not just children, cockroach allergen is the most common cause of asthma in the elderly.

What Causes the Asthmatic Reaction?

The cockroach allergens that produce asthma symptoms in people are proteins that come from cockroach feces, other body secretions, saliva, egg cases, shed cockroach skins, and dead cockroach bodies. These body proteins are left behind in places where cockroaches have traveled or have been hiding. The proteins can become airborne and be inhaled or can settle on new surfaces. Since cockroach feces and egg cases are left in hidden cracks, crevices, and voids where cleaning doesn’t reach, the allergens can remain for years.

Control and Cleaning Are Not a Cure-All

The bad news is that more recent studies have found that even after the roaches are gone from a residence, most of the allergens remain. Getting rid of the cockroaches in the residence will certainly remove some allergens and will prevent the accumulation of future allergens, but cockroach allergens are very resistant to cleaning. Even professional cleaning has been found to leave enough cockroach allergen behind to still affect most people already sensitized to cockroach allergen. See Cockroach Allergen Levels Remain Despite Efforts.

Does this mean you shouldn’t even bother to try to remove cockroaches and their allergens? Of course not. The longer that cockroaches are present in a home, the greater the accumulation of allergen material, so early control is important. While cleaning won’t remove all of the allergens present, it may drop the allergens to a low enough level that some less sensitive asthmatics may no longer be affected.

Photo: Gary Alpert, Harvard University, Bugwood.org

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