More than 4.1 million children in this country suffer from asthma, and studies show that the number is on the rise and severity has also increased in the past 30 years. Asthma is a chronic inflammatory disease that obstructs airways and makes them overly sensitive to irritants. For 90 percent of children, the disease is allergic in nature. Common allergic triggers are pets, pollens, dust mites, mold and feathers. Attacks may occur after exposure to irritants (cigarette smoke, strong odors, household cleaning products, workplace chemicals), viral respiratory infections (colds, flu), sudden changes in weather or emotional stress, wrote UTMB Drs. Sally Robinson and Keith Bly in their Keeping Kids Healthy column.