Asthma, reports the CDC, is the number one reason for school absenteeism in America. While wheezing is a symptom of asthma, also look for persistent coughing or repeated episodes of bronchitis or pneumonia, advises Karp. The best way you can protect your child from recurrent attacks is to become an educated parent. Since asthmatics have hyperreactive airways, a number of allergens or irritants may cause the lungs' breathing tubes to close, restricting the breathing. Technically an airways irritant rather than an allergen, smoke has a severe effect on asthmatics.
Dust mites .
The excrement of this microscopic mite is a potent allergen. Mites infest bedding, upholstery, draperies and rugs and thrive on moisture and human skin cells. Cockroaches are a primary allergen. Pet danders . Cat, dog and horse danders, and bird feathers can cause severe reactions.