2007 – Seven USA cities prove that allergen avoidance benefits asthmatics

Inner city children with asthma demonstrated clinical benefits through an individualized allergen recognition and avoidance programme.
In a large clinical study in seven U.S. cities, 937 asthmatic children (age 5 to 11) were individually clinically tested for allergy triggers and exposure to tobacco smoke. The study then evaluated the effectiveness of multifaceted, home based, environmental interventions designed to improve individual morbidity and decrease their use of health care services. Common allergens detected were from cockroach, cat, mould and house dust mites. The goal of the study was the modification of behavioural change through interventions and education. Interventions included, allergen-impermeable covers on mattress and pillows to reduce mite exposure, vacuum cleaners with a HEPA filter or bare-floor brush for cleaning hard floors, professional pest control visits if cockroach was discovered. In addition, if passive smoke, mould, dog or cat allergens were identified as triggers, a HEPA air purifier was installed in the child’s bedroom.

The study demonstrated sustained reductions in indoor allergen levels and sustained improvements in reported asthma morbidity. A year-long study with one year follow-up.


‘Results of a Home-Based Environmental Intervention among Urban Children with Asthma’, Morgan W J et al, 2004: 351: p 1068-80, New England Journal of Medicine