What is asthma?

Asthma is a disease of the lungs that causes the airways to:

  • Become swollen or irritated (called inflammation) specifically in the airway linings
  • Produce large amounts of mucus that is thicker than normal
  • Narrow because the muscles around the airways tighten

Asthma is very common; it affects about 22 million Americans which include about 6 million children under the age of 18. It is the most common chronic condition of childhood. Uncontrolled asthma can lead to missed work and school days, interrupted sleep patterns and, ultimately, poor work and school performance.

What are allergies?

Allergies are when the body reacts to something that does not affect most people. . Substances that cause allergies are called "allergens" and include things like pollens, molds, animal dander, and dust mites. Some people are also allergic to medications, foods and latex (rubber) products. Allergy symptoms include sneezing, watery eyes, itchy eyes and nose, coughing, and sometimes a rash or hives. Allergy can be a trigger for people with asthma and can cause shortness of breath, cough and wheezing.

What has been the effect of asthma and allergies on society?

  • Approximately 23.3 million Americans have asthma, including 7 million children. About 70% of people with asthma also have allergies.
  • 13 million school days and 10.1 million work days are missed annually due to asthma.
  • Approximately 3400 deaths occurred in 2005 from asthma.
  • Total costs for treatment of asthma in the US are $20.7 billion annually [direct costs total $15.6 billion, and indirect costs (e.g., lost productivity) total an additional $5.1 billion].
  • Allergies affect 40 to 50 million Americans.
  • Allergies are the sixth leading cause of chronic disease in Americans.
  • Approximately 60 million Americans have hay fever (seasonal allergic rhinitis).
  • Total costs of allergies almost doubled from 2000 to 2005 ($6.1 billion to $11.2 billion).
  • Skin allergies (e.g., dermatitis) occur in 10 to 20% of American children and 1% to 3% of adults.
  • 40 deaths per year occur as a result of anaphylaxis due to insect stings.
  • Food allergy affects 3 to 4% of adults and 6% of young children.

What causes asthma?

The cause of asthma is uncertain. Among those at higher risk for asthma are those who:

  • Have a family history of asthma
  • Have a history of allergies
  • Have smokers living in the household
  • Live in urban areas

Triggers are things that make your asthma symptoms start up or get worse. Asthma triggers include allergens, exercise, irritants (strong odors from cleaning products, perfumes, etc, wood smoke), tobacco smoke, infections (colds, flu), weather changes (changes in temperature and/or humidity), and emotions such as laughing or crying.

What are the symptoms of asthma?

The symptoms of asthma are:

  • Feeling short of breath
  • Frequent coughing, especially at night
  • Wheezing (a whistling noise during breathing)
  • Chest tightness - feels like something is pressing or squeezing the chest

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