Billions of ragweed pollen grains cause most seasonal allergies
(21 July 2005: VIDYYA MEDICAL NEWS SERVICE) -- Ragweed is a prolific pollen producer and the number one cause of seasonal allergy symptoms according to the American College of Asthma, Allergy and Immunology (ACAAI).
“A single ragweed plant can produce up to 1 billion pollen grains, and each grain can travel more than 100 miles from its source,” said Richard W. Weber, M.D., National Jewish Medical and Research Center, Denver, and chair of the ACAAI Aerobiology Committee that specializes in pollen and mold allergens.
“Throughout much of the country, people with pollen allergies already have suffered through high pollen counts from spring pollinating plants. Once the dry weather conditions of late summer and autumn take hold, ragweed’s profuse pollen is released into the air, accounting for 75 percent to 90 percent of all pollen found from August through October in some regions,” Dr. Weber said.
“Peak ragweed pollen counts start first in the North, hitting around Labor Day. Southern states experience peak conditions in late September or mid-October. But if people are prepared and know what to do, they can get through it with a minimum of discomfort,” he said.
Allergists – doctors who specialize in treatment of allergic diseases including asthma – want people to know that increasing amounts of ragweed pollen in the air can also trigger life-threatening asthma symptoms such as wheezing and difficulty breathing.
Children with allergies are particularly at risk of developing asthma during peak pollen seasons. A three-year study of children with seasonal allergies found that 1 in 5 experienced asthma symptoms during pollen season, even though they had no previously reported history of asthma.
"Noted aerobiologists agree that the time of day when pollen is at peak levels will vary from plant to plant," said allergist-immunologist Warren V. Filley, M.D., Oklahoma City, Okla. "Ragweed pollen is released onto the plant leaves at daybreak, then depending upon the dew and wind conditions, it usually is at it highest airborne level between 10:00 a.m. and noon, but this is variable."
The ACAAI recommends the following actions to minimize ragweed pollen allergy symptoms:
-- Begin allergy medications one or two weeks ahead of the ragweed season. The best medications work by inhibiting the immune system’s release of chemicals that can cause allergic reactions and, if taken prior to exposure to pollens, can help stabilize your immune system before you experience symptoms. Talk to your family doctor or an allergist about the best medications for you.
-- If medications don’t provide sufficient relief or if you experience medication side effects, talk to an allergist about allergy shots, or immunotherapy. Allergy shots can provide long-term relief by stimulating the immune system to fight allergies safely, effectively and naturally. Immunity does not occur immediately, but you can expect some relief quickly. You also may be a candidate for “rush” immunotherapy, a type of vaccination process that speeds up the development of immunity.
-- When gardening or mowing the lawn, wear a particle mask.
-- Take your allergy medications before going outdoors.
-- Wear sunglasses to keep pollen from getting into your eyes.
-- After being outdoors, bathe and wash your hair, change your clothes and use a nasal salt water rinse to remove pollens.
-- Check out your local television or newspaper weather reports for pollen counts and forecasts. When counts are high, avoid outdoor activities.
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