Indoor Air Cartoon Journal, April 2019, Volume 2, #53

Parents often worry when their child coughs or suffers from other asthma-related symptoms, especially during the time they are supposed to be sleeping or resting. Unknown to most parents, their child may be exposed to dust mites in the dust – fine particles – on the bed mattress, blankets, or pillow casings. Disturbance of the dust particle on these surfaces during sleep movement increases exposure. Dust mites grow by feeding on human skin cells shed in the dust. Dust mites release allergens that irritate respiratory system when inhaled. Unfortunately, the presence of dust mites on the bed is ubiquitous. High concentration of dust particles on bed blanket, bed sheets, mattresses, and pillow casings coupled with high humidity will increase the risks of a child experiencing allergic asthma. Building occupants in a warm and humid climate are more susceptible to dust mites exposure.

Medical treatment can help alleviate the adverse health effects caused by dust mites, but it is not a sustainable solution required to reduce the risk of childhood allergic asthma. It does not address the root cause of the problem. If a child continues to sleep in a dust mite invested bed at home or school, his or her allergic asthma or other respiratory adverse health effects will continue to get worse. Even a child with no asthma condition may suffer from cough when exposed to dust mites. Efforts should be made to reduce outdoor to indoor transport of dust particles and human activities that generate dust in the indoor environment. Indoor humidity level should also be controlled to avoid dampness.

As the presence of dust on indoor surfaces is inevitable, cleaning efforts become essential. The frequency and effectiveness of cleaning efforts depend primarily on human behaviour. Poor house cleaning habits, non-regular changing or inadequate cleaning of bed blankets, bed sheets, mattress, or pillow casings will enhance the breeding ground for dust mites to grow. Poorly ventilated bathroom or poorly controlled pressure difference that allows moisture from the toilet to flow into adjacent bedroom or classroom where a child sleeps will also increase exposure to dust mites not only for the child but for other occupants. It is important to note that exposure to dust mites could also occur on carpets and furniture. It is essential to reduce the amount of settled dust in the indoor environment as much as possible as dust could house other allergy triggers.

Do you want to know more about this topic? Read Halken et al. (2003), Sarsfield (1974), and Zhang et al. (1997) papers.