Pollen counts so far: Up, down, up, down

Donald Dvorin, allergist and cofounder of the Asthma Clinic, is the region's semiofficial pollen counter.
Donald Dvorin, allergist and cofounder of the Asthma Clinic, is the region's semiofficial pollen counter. (AKIRA SUWA / Staff Photographer)
Posted: April 04, 2013

In some seasons, pollen is up. In others, down. And then there are those - like this one - that are all over the place, with cold following warmth following cold following warmth, nipping the buds every time they start to, well, bud.

Tuesday's tree-pollen counts locally were the highest so far this season, but still less than a sixth of last year's high, and a potentially suppressing rain was predicted for Friday. Counts are rising late this spring.

"Last year was a mild but quite moist winter, and the season started earlier and lasted longer," said S. Michael Phillips, director of clinical allergies and immunology at the University of Pennsylvania. "If the plants are happier, they are going to make more pollen."

He predicted an average or slightly worse than average allergy season overall.

But average is just that - better in some ways, worse in others, and complicated by variations in individual responses to one pollen or another.

Jeanette Bioteau, 46, has never had more than mild seasonal allergies. But for many months now, she has had trouble sleeping and wearing contacts.

"I had an allergy test for the first time today," she said Tuesday. "I'm allergic to trees and grass and also to dogs and cats," which is unpleasant news, since she likes to walk her three dogs in the park.

"My three daughters" - ages 6, 9, and 12 - "started crying, saying 'Please don't tell us we have to get rid of the dogs, Mommy,' and I said 'No, we're not getting rid of the dogs,' " said Bioteau, a registered nurse in University City. Her doctor prescribed Flonase nasal spray and suggested she buy air filters and over-the-counter antihistamines, close windows, and lock pets out of the bedroom.

One thing in the allergy world that has changed for the better over the last 15 years or so is non-sedating antihistamines. "They don't cross the blood-brain barrier, so they don't make you tired," said Joanna Johnson, a pediatric allergist at St. Christopher's Hospital for Children. But some people also complain they are less effective.

Many things have changed for the worse, starting with warmer winters that welcome new plant species and encourage trees to bloom earlier - "in recent years, maybe a week to 10 days earlier than they have in the past," said Paul Meyer, executive director of the Morris Arboretum.

He said that moisture was not a significant factor in when trees bloom, but that rain does wash the pollen out of the air. Wind blows it into your eyes.

Spring freezes can kill buds. Mere coolness simply delays their opening.

Temperatures have moved from warm to cool and back again "at least three times in the last three weeks," said Donald J. Dvorin, an allergist and cofounder of the Asthma Center, with nine locations in Philadelphia and suburbs in both states.

Dvorin is the region's semiofficial pollen counter - a certified pollen and mold spore collector - whose daily reports run on The Inquirer's weather page. They are posted at www.asthmacenter.com and recorded by the American Academy of Allergy, Asthma & Immunology.

Between 7:30 and 8 every morning, he manually checks his Burkard Spore Trap on the roof of his Mount Laurel practice; a manager at the Center City offices gets that one.

Tuesday's tree-pollen counts were 429 in South Jersey and 237 in Philadelphia, both the highest so far this season. They can change quickly, often due to the weather. On April 17 last year, they peaked at a higher-than-usual 2,773 in Jersey and 2,508 in the city.

Physicians say that some people feel allergies at 100 tree pollen grains per cubic meter of air - a few as low as 10 - and most feel symptoms at 300. Anything over 400 is considered very high.

First to bloom, typically around mid-March, are the junipers, elms, cedars, and maples, followed by birches, oaks, and walnuts. "If we don't get into warm-weather-producing pollen soon, we may have a lower season in general," said Dvorin.

Grass-pollen season usually runs from late April through late June. Then there's a reprieve until highly potent ragweed and marsh weeds kick in around early August through the first frost.

Over the last five years or so, presumably because of climate change, a second grass season has appeared for a few weeks in September, Dvorin said.

And more and more people are reporting symptoms, up from less than 5 percent in urban areas 25 years ago to more than 20 percent now, said Phillips, the Penn allergist.

Weather isn't the only reason. But human activity is blamed for the other key explanation, known as the "environmental hypothesis."

As antibiotics and lifestyle changes have cleaned up the environment in developed countries, Phillips said, the "yin-yang relationship" of two key parts of the immune system have been thrown off balance.

With the group of immune cells that targets bacteria having less to do, the counterpart immune cells, which specialize in parasites - and see pollen as parasitic invaders - have gone into overdrive. The chemicals they release to attack invaders cause itching and swelling. Lower in the lungs, they trigger coughing. Lower still, asthma.

Human activity changes things in unexpected ways. "Ragweed plants near roads, with more pollution," Phillips said, "grow bigger than ragweed away from a highway."


Contact Don Sapatkin

at 215-854-2617 or dsapatkin@phillynews.com.

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