Our pollens exceed rest in U.S., making us sneezy and grumpy.

Byline: THE HEALTH FILES By Tim Christie The Register-Guard

The medical term is seasonal allergic rhininitis. In plain terms, it's hay fever. For sufferers here in the southern Willamette Valley, it's three months of misery.

We're talking, of course, about spring allergy season, now in full bloom as a succession of trees release their pollens into the air. Next up: the dreaded grass pollen season.

This year's allergy season didn't begin any earlier than usual, but it has been more intense. A stretch of unseasonably sunny, warm weather this spring along with heavy loads of tree pollens means more pollen has been hanging around in the air, said Jean Jensen, a research nurse at the Allergy & Asthma Research Group in Eugene, part of a private allergy clinic.

"When it doesn't rain, the pollen stays suspended," she said. "People are more exposed, because they're outside more."

The result is more patients are calling allergy clinics to complain of itchy eyes, sneezing and runny noses.

Part of Jensen's job is to count grass, weed and tree pollens every day. The pollens - along with dirt and mold spores - are collected in a machine mounted on the second floor of a medical clinic on Oak Street in downtown Eugene.

Every morning, Jensen takes out a microscope slide that's been in the machine for 24 hours and replaces it with a clean, greased slide. She takes the dirty slide, stains it with four drops of red dye, then counts and identifies the pollens she finds, looking for telltale shapes, pores and furrows. The counts are posted at the Web site of the American Academy of Allergy Asthma and Immunology (www.aaaai.org).

Trees begin releasing pollen as early as December, "but we might not notice it if it's raining," Jensen said.

Filberts and cedar trees release pollen first, followed by alder and ash, then maple and oak. Walnut caps the tree pollen season in late May or early June.

Ash and birch pollen were prevalent last week, peaking at 397 pollens per cubic meter on Tuesday; the American Academy of Allergy Asthma and Immunology considers any count over 90 to be of high severity.

The grass pollen season peaks between Memorial Day and the Fourth of July.

Grass pollen counts in the southern Willamette Valley are off the charts compared with other regions of the country, allergists say.

Any grass pollen count over 200 pollens per cubic meter is considered "very high" by the national allergy group. We get counts of 400 and 500 per cubic meter routinely, and sometimes they surpass 1,000 pollens per cubic meter. Sometimes the pollen here is so thick that even nonallergy sufferers start feeling allergylike symptoms when the pollen starts clogging their mucous membranes.

The valley's geography and agriculture conspire to create perfect conditions to make life miserable for people allergic to grass pollen. About 80 percent of the world supply of rye grass seed is grown on 200,000 acres in Lane and Linn counties. Mountains on either side create an enclosed air shed, and prevailing winds trap pollens in the valley.

If you're one of those poor souls sickened by grass and tree pollens, you're not alone. As many as 35 million Americans suffer from seasonal allergies, according to the National Institute of Allergy and Infectious Diseases.

While everyone gets exposed to pollens, not everyone gets sick. Allergies develop when the immune system overreacts to a normally benign substance. When antibodies, designed to fight invaders, encounter allergens such as pollens, they trigger the release of little packets of chemicals, including histamines and other compounds that cause common allergic symptoms: sneezing, coughing, postnasal drip, itchy eyes and a runny or clogged nose.

Predicting the severity of the allergy season is difficult, Jensen said.

"Certainly if the weather stays like it has been, we're going to see some miserable folks," she said.

Tim Christie can be reached at 338-2572 or [e-mail].

COMBATTING SEASONAL ALLERGIES

Avoidance: Stay indoors as much as possible with doors and windows closed and air conditioner on. Don't drive with the windows down. Take a day trip to the coast or the mountains.

Medicate: Various antihistamines are sold over the counter; Claritin and its generic equivalent, Alavert, are effective for many allergy sufferers. Prescription drugs include Allegra and Zyrtec. Steroid nasal sprays, sold by prescription only, also provide relief for many.

Immunotherapy: People with symptoms severe enough to disrupt their work or social lives, or who develop asthma, may consider getting a series of allergy shots that get the body's immune system to tone down its attacks on allergens.