Causes and Risk Factors of Hay
is inflammation of the mucous membranes in the nose. It’s often caused by
common colds and other viral infections. Allergic rhinitis, also known as hay fever,
is the most common form of rhinitis. It causes irritation of the nasal
membranes due to different airborne allergens.
allergy is an immune system response. Your immune system’s job is to protect
you from outside invaders such as viruses, bacteria, and parasites. Sometimes
your immune system mistakes something harmless for an invader. When this
happens, you develop antibodies to fight the harmless substance.
antibodies involved in hay fever are immunoglobulin E (IgE) antibodies, which
are the normal antibodies the body makes to fight parasitic infections. The
first time you are exposed to an allergen like pollen or dust mites, your body
makes IgE antibodies to “defend” against it. This is called sensitization. The
next time you are exposed, those IgE antibodies go to work to destroy the
allergen. They do this by inducing the release of histamines and other
chemicals that cause the inflammation and other symptoms of allergy.
hay fever is usually caused by outdoor allergens. It commonly affects
people from spring through fall, depending on when certain plants and trees
release pollen into the air. Allergens that frequently cause seasonal hay fever
- tree pollen (in
- grass pollen (in
the late spring and summer)
- weed pollen (in
- fungi and mold spores (in the warmer parts of the year)
(perennial) hay fever
is usually caused by allergens other than pollen, most often those found in the
home. These include the following:
- animal dander: Cats
in particular are the cause of allergy symptoms for many people because
they frequently lick their coats. This releases dander and inflammatory
proteins from their saliva into the air. Unlike dogs, cats tend to closely
share living spaces with their owners and houseguests.
- indoor mold: Mold
grows in damp, dark areas of a home. A kitchen can be especially
problematic for perennial rhinitis sufferers, who are more likely to have
both outdoor and indoor allergens affect them.
- dust mites.
These are microscopic bugs that live in house dust. They may be
found in bedding, upholstery, and carpets.
- cockroaches. These usually live in moist, warm
hiding areas, such as near standing water or sweating pipes, under the
sink, and wall or floor cracks. Cockroaches tend to live near food
supplies. They also eat newspapers, book binding, and wallpaper paste.
hay fever may also be caused by extreme sensitivity to plant pollens throughout
triggered by any of these allergens, the allergic reaction is caused by the
release of histamine and other chemicals. These cause the swelling of nasal and
eye tissues, the secretion of mucus, and, possibly, the constriction of
factors that may increase your risk of developing hay fever are described
High IgE Levels
fever usually begins at an early age. Children under 6 years old who are tested
for immunoglobulin E (IgE) levels will be at risk for hay fever if serum IgE is
greater than 100 international units (IU) per milliliter (mL).
family history of hay fever or asthma increases your risk for developing
or working in an environment that consistently exposes you to allergens, such
as dust mites and pollen, can greatly increase your risk of developing hay