WHAT IS HAY FEVER?

Hay fever is the name given to pollen allergy. Other terms for hay fever include "seasonal allergic rhinitis" or "pollinosis." If you have hay fever, you are not alone. An estimated 26.1 million Americans have hay fever symptoms each year. 14.6 million Americans have asthma, which can often accompany hay fever.

HOW HAY FEVER OCCURS

Anyone can develop an allergy to a common substance, but those who do usually have inherited the tendency as a family trait. The sensitivity is developed after exposure to the substance. Hay fever is a good example of this process.

During the seasons when plants are pollinating, everyone in the surrounding area is exposed. People with allergic tendency may develop sensitivity to any one or more of the pollens, although certain pollens are more likely to cause an allergic reaction than others.

Pollens that are light enough to be wind-borne are what cause the problem for most hay-fever sufferers. Heavier pollens that are carried from plant to plant by bees and by other insects can also be allergens, but they cause trouble only when a person comes into direct contact with the plant. Airborne pollens can penetrate anywhere, indoors and out, and are most numerous at the height of the pollinating season for the particular plant.

WHAT ARE THE SYMPTOMS FOR HAY FEVER?

Sneezing that is repeated and prolonged is the most common mark of the hay fever sufferer. A stuffy and watery nose is also a main sign of hay fever. Other symptoms include redness, swelling and itching of the eyes; itching of the nose, throat and mouth and itching of the ears, or other ear problems. Breathing difficulties at night due to obstruction of the nose may interfere with sleep.

These symptoms differ in degree according to the individual, ranging from mild to severe. When severe, they are very uncomfortable, make it difficult to carry out daily tasks, and may cause loss of time from work and school.

Health complications from repeated hay fever attacks, year after year, may be an even more serious problem. Chronic sinusitis -- inflammation of the sinus cavities -- is one of these problems. Another is nasal polyps, or growths. In addition, a significant percentage of people with hay fever have or develop asthma.

THE SEASONS FOR HAY FEVER

The "hay fever season" can be a different time of year for different people. In part, this is because trees, grasses, and weeds produce pollens during different seasons. For example, people in the eastern and Midwestern United States who are sensitive to tree pollen may suffer in the early spring when trees such as elm, maple, birch and poplar are producing pollen. People who are sensitive to pollens produced by grasses may suffer in the late spring, and early summer, the time when most grasses are pollinating. About half of all hay fever sufferers are sensitive to grass pollens.

Weeds flourish in most parts of the country from midsummer to late fall. In the late fall, ragweed is the most common problem. In fact, ragweed is the plant that causes the most hay fever. But an individual may react to one or more pollens in more than one of these groups, so the person's "season" may be from early spring to the first frost.

For that matter, people who are sensitive to dust, to dog or cat dander (tiny scales or particles that fall off hair, feathers, or skin) or to other some other airborne material that they cannot protect themselves from may suffer all year round.

Mold and fungus spores ("seeds"), also airborne during the summer and fall months, cause reactions in many people. Frequently found around hay, straw, and dead leaves, their growth is encouraged by humid weather and by places with poor air circulation--damp basements for instance.

SENSITIVITY AND HOW IT WORKS

"Sensitivity" is the term used to describe the process by which you develop an allergy. Sensitivity is established when the tissues that form antibodies (lymphoid tissues) are stimulated to make specialized antibodies to otherwise harmless pollens, spores, etc. These antibodies fix to other specialized cells throughout the body that contain powerful defensive substances such as histamine. When the individual next is exposed to the pollen (as in the nose, for instance), the antibodies trigger the cells to secrete their defensive substances. This in turn causes the dilation of blood vessels, increased secretions of fluids, swelling of tissues, itching, sneezing, and other reactions that add up to hay fever.

The inflammation and other symptoms -- while real enough -- actually are not of the same destructive nature as those carried by more serious diseases. Removing the cause of the reaction results in immediate relief.

HOW TO CONTROL HAY FEVER

Avoiding the substance that causes a reaction is the best way to control hay fever. Moving to a different part of the country is sometimes suggested, but taking this drastic and expensive step may prove useless if the person has or develops sensitivity to a substance common in the new location.

Using air conditioning and air purifying devices may help cut down on suffering during the hay fever season, so that normal sleep and work are possible. Dust masks should be used during outdoor work if the work cannot be avoided.

Antihistamines - drugs that counteract the histamine released by the allergen-antibody reaction (see "Sensitivity And How It Works," above ) - usually serve to give relief from some symptoms. Decongestants may help, as well. However, they don't affect the underlying sensitivity. Each individual has to depend on his or her doctor to find out what drug or combination of drugs works best.

Over-the-counter nose sprays are usually of limited value and their prolonged use may actually cause symptoms or make them worse. Inhaled steroids are often effective and may be prescribed by a doctor. Specific desensitizing injections are a commonly used treatment.

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