UNIT 7: SEASONAL ALLERGIES & ASTHMA SC330 Immunology

Seasonal Allergies Image credit:

Seasonal Allergies Also known as hay fever, it is an immediate hypersensitivity in the nasal passages caused by environmental antigens (allergens). Seasonal allergies usually develop after age 6. The resulting allergic rhinitis & sinusitis is a histamine-triggered inflammation of nasal passages. Allergens are from the pollen of wind-pollinated plants: 1.tree pollen (especially birch) 2.grass pollen (especially rye grass) 3.weed pollen (especially ragweed)

Allergic Asthma Image credit: asthma+mites.jpg

Allergic Asthma 80% of asthma in children & 50% in adults is caused by allergies (American College of Allergy, Asthma, and Immunology). 90% of people with allergic asthma and 10% of the general population are sensitive to dust mites. Seasonal allergies frequently precede the development of allergic asthma.

Causes of Allergies & Allergic Asthma Image credit:

Causes of Allergies & Allergic Asthma Why are allergies & allergic asthma increasing? Possible causes of increased allergies: 1.low parasite infection rates: normal targets of IgE 2.excessive cleanliness & unnecessary vaccinations: low antigen exposure during childhood 3.same foods year-round 4.technology:AC, cars, vacuums, carpeting, etc. 5.pollution 6.stress 7.breast feeding: bottle-fed babies have more allergies than those breast-fed

Causes of Allergies & Allergic Asthma Do we clean our children too much? Early exposure to agents can result in lessened/no symptoms. Continuous stimulation of the immune system by “filth” helps establish a broad, well- developed immune response. Image credit:

Causes of Allergies & Allergic Asthma Cleanliness is next to godliness. Unique to America, we associate cleaning & religion. Americans are obsessive/compulsive about cleaning. Without valid antigenic exposure, a child’s idle immune system begins to attack mild antigens in food & environment. Image credit:

Treating Allergies & Allergic Asthma Treatments include: 1.avoiding allergens (cleaning & filtration) 2.antihistamines (Claritin) 3.decongestants (Zyrtec, Sudafed, & Allegra) 4.corticosteroids (Flonase, Advair, & prednisone) 5.bronchodilators (Ventolin, Proventil, & Pro-Air) 6.mast cell stabilizers (Intal, Tilade, & Crolom) 7.leukotriene modifiers (Accolate, Singulair, Zyflo) 8.anti-IgE antibody injections (Xolair) 9.immunotherapy (allergy shots)