What Is It?
Asthma is a common respiratory condition which affects people of all ages. It is the most common disease of childhood. In Canada, about 15% of children have asthma. The incidence and mortality rates of asthma are increasing worldwide. At present, there is no known cure for asthma, but understanding how asthma affects the lungs and controlling asthma symptoms can improve the quality of life.
People with asthma have extra sensitive airways. Three things happen to the respiratory system during an asthma attack: the muscles around the bronchi (air tubes) tighten; the inner linings of the bronchi swell; and an excessive amount of mucus is produced. As a result, it is difficult for the child with asthma to breathe.
Many children with asthma have a relatively mild form, which is fairly easily controlled. Other children with moderate or severe asthma may exhibit more symptoms, including dry cough, wheezing and difficulty breathing. On occasion, any asthmatic child may experience severe breathing difficulty. Such episodes should be regarded as emergencies requiring immediate treatment.
Causes
Causes of asthma differ from person to person. Asthma triggers are the things that cause asthma symptoms. Common triggers include:
- allergic reactions
- the most common allergens are house dust, pollen, mold, animal dander, latex, feathers and foods
- respiratory infections and colds
- exercise;‚ air pollution, fumes, chemical odours or other strong odours
- cigarette smoke
- exposure to cold, windy or humid air, or sudden temperature changes
- fatigue, excitement or stress.