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It's the Season for Sneezin' : Allergies: After a wet winter and a green spring, a bumper crop of pollen awaits O.C.'s estimated 360,000 hay fever and asthma sufferers.

March 30, 1993|STEVE EMMONS | TIMES STAFF WRITER

During five years of drought, the crackly-dry, brown hillsides of Orange County were a beautiful sight to allergy sufferers. They signaled a pause in the usual onslaught of spring pollen.

Now, after the wettest winter and greenest spring in 14 years, a bumper crop of pollen awaits Orange County's estimated 360,000 hay fever and asthma sufferers.

"We're probably going to see the worst of it in April, May and June, and we'll probably have a bad fall, too," says Dr. William E. Berger, an allergist and associate clinical professor at the UC Irvine College of Medicine. Late summer may have more than the usual mold spores as well, he added

So far, tests of Orange County's air have confirmed expectations. According to Dr. Mark H. Ellis, an allergist in Orange, tree pollen has been at times triple the levels of the same times during the last three years. And mold spores rose to 10 times previous concentrations during periods this winter of rain followed by warm weather.

Grass pollen, which usually peaks later in the spring, was already double the three-year norm. Weed pollen, a fall phenomenon, was already showing up in the air.

This means a lot of itchy eyes, runny noses and wheezy lungs in store for Orange County, yet it's all so unnecessary. All this misery results from a misunderstanding. The body is mistakenly trying to protect itself from a threat that does not exist.

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Inhaling pollen and mold spores is harmless to humans, says Dr. Harold Novey, an allergist and clinic professor at UCI. But about 15 in 100 people have bodies genetically programmed to mistake pollen and mold spores for dangerous foreign bodies, and their immune systems pour out antibodies to attack them.

The body produces five kinds of antibodies, but the hay fever sufferer produces a larger-than-usual amount of the type called IgE.

These attach themselves to white blood cells, where they are carried on patrol throughout the bloodstream. But they also attach to cells in the skin and in the linings of the lungs, airways, stomach and intestines. There they wait like sentries at the places where the body has contact with the outside world.

When a microscopic grain of pollen floats by and sticks to an IgE antibody, the antibody sounds the alarm, and the cell to which it's attached fires a volley at the intruder.

The weapon is histamine, a substance ill-suited to the purpose. It seems to have no real function nowadays, Novey says. Researchers guess it evolved early in human history to combat parasites that are no longer common in our environment.

Marshaling such a powerful weapon against a grain of pollen is like attacking a roach with a chain saw. The roach is likely to escape, and the walls are likely to suffer.

In the normal person, there are too few IgE antibodies to provoke a noticeable reaction. But in the allergic person, repeated exposure to pollen or the like builds up a huge store of IgE.

Some babies already have IgE antibodies, developing them in the womb or receiving them through nursing. Others build up their supply over three to five years of exposure.

You can run, but you can't hide. Many people have left the ragweed-infested East for the "clean" air of the Southwest. But in three to five years, they usually built up another set of antibodies that react to whatever is floating in the local air, Novey says.

Eventually there are enough antibodies to create a large outpouring of histamine, and allergy symptoms begin.

The histamine contracts the gut and the airways, in rare cases closing them off entirely. It opens blood vessels, and blood pressure falls. In severe cases, the heart beats irregularly. Some people, such as those allergic to bee or fire ant venom--produce massive amounts of histamine, because the venom enters the bloodstream where the IgE begins firing throughout the body. Shock and death are a real danger in such circumstances.

Histamine does its work by attaching to the body cells it affects. Antihistamines--the common allergy and cold drugs sold over the counter and by prescription--counteract this process by attaching to cells in place of the histamines, thereby crowding them out.

The most common side effect of such drugs is drowsiness, although that has been greatly reduced in newer prescription drugs such as Seldane and Hismanal. Researchers now are concentrating not on counteracting histamine but on preventing it from being discharged.

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Within the past five years, researchers have discovered that T cells, one type of white cell in the blood, provoke the formation of the IgE antibody by secreting a substance called cytokine. The hope is that drugs can interfere with this process without serious side effects. If so, the allergic reaction might be prevented permanently, Novey says.

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