Asthma is a chronic inflammation of the body’s bronchial (airway) tissues that afflicts millions of people in the United States. People with asthma experience shortness of breath, chest tightness, coughing and wheezing. These symptoms intensify during an asthma attack, which occurs when exposure to allergens or other stimuli further inflame the airways, leading to an inability to expel trapped air from the lungs. Most asthma attacks are mild, but even people with mild asthma can have a fatal attack, and more than 5,000 deaths a year are attributed to the condition.

The number of Americans with asthma has surged in recent years. According to the National Heart, Lung and Blood Institute, approximately 20 million people have been diagnosed with asthma. Greater numbers of children now have asthma than in the past (nearly 9 million), and poor children in urban environments have been hit particularly hard. On the other end of the spectrum, Americans over age 65 make up the nation’s largest group of asthmatics.

Asthma is diagnosed using a number of breathing–related tests and by ruling out other respiratory conditions, such as chronic obstructive pulmonary disease and emphysema. About 70 percent of people who have asthma also have allergies, according to the American Academy of Allergy, Asthma and Immunology (AAAAI). Like allergies, asthma may be passed down. A person is more likely to develop asthma if one or both parents have the condition.

There is no cure for asthma, but once diagnosed, it is a highly treatable condition. Various asthma medications can help prevent asthma attacks, or treat them once they have begun. Asthmatics can also modify their environment and day-to-day behavior in ways that reduce the likelihood of an asthma attack.

Some children with asthma may eventually see their symptoms subside as they grow older, but asthma is never actually “cured,” and symptoms can reoccur at a later date. Others see their symptoms worsen as they grow older.