Early Life Exposure to Dust May Protect Against Asthma

[Angel]

Exposing children early in life to dust and other microbial agents could protect them from developing asthma, according to new research in the Journal of Allergy and Clinical Immunology (JACI).

The title of the study, by Jeroen Dowes, PhD, Utrecht University, the Netherlands, and Massey University, Wellington, New Zealand, and colleagues, is "Does early indoor microbial exposure reduce the risk of asthma? The Prevention and Incidence of Asthma and Mite Allergy birth cohort study".

Researchers initially assessed children's exposure to microbials at 3 months of age and then followed the children, all of whom have atopic mothers and live in the Netherlands, to age 4. Microbials are small, inhalable particles that are, or have been living agents.

Through those 4 years, they monitored the development of atopic sensitization (which can lead to allergies), doctor-diagnosed asthma and wheeze in the children. In addition, the researchers measured dust on living room floors and infants' mattresses at 3 months of age, serum IgE levels for common allergens at one and four years of age and collected yearly information related to whether or not the children had developed asthma. A random group of participants was also given mite-impermeable mattress and pillow covers; the other group was given a placebo of cotton mattress and pillow covers.

While microbial levels in mattresses were low and not associated with allergy, doctor-diagnosed asthma or wheeze, the study showed levels of dust and other microbials on the floor correlated to a lower level of asthma development by age 4. The highest exposure group had a lower level of asthma and wheeze, even when researchers made adjustments for the presence of animals in the home, antibiotic use, dampness, etc.