Everything seems to be in bloom this June in many parts of the country. That can be nice for outdoors enthusiasts, but not so much for those who suffer from allergies. Along with itchy eyes and a runny nose, people with allergies often complain they catch every cold going around.

One expert, Neil Kao, a fellow of the American Academy of Allergy, Asthma and Immunology, explains when white blood cells get overexcited and how a shower can be an allergy-sufferer’s best defense against the summer cold.

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On the Hunt
The immune system works to distinguish normally functioning cells from sickly ones or external agents such as bacteria or viruses that cause disease. It does that by sending out white blood cells to “sample” the receptors on foreign-seeming cells.

“It’s sort of like touching your own hair and saying, ‘Oh, right, that’s me, move along,’ ” the Greenville, S.C., allergy specialist says.

Another big role the immune system plays is to destroy the cells that are foreign, damaged or cancerous. Pollen, dander, dust and mold comprise part of the normal universe. They should be sampled, deemed neutral, then left alone, Dr. Kao explains. But if you suffer from seasonal allergies, your immune system overreacts.

“Your body thinks the allergens are the front-line, and they attack,” Dr. Kao says. “It’s bad. It can feel like you didn’t get a good night’s sleep every day, all season.” If you don’t have seasonal allergies, he adds, “you can’t appreciate how bad it feels.”

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