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allergy
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allergy
What does hypoallergenic really mean for consumer products?
anaphylaxis skin test
Why do people have allergies in the spring?
Learn about hygiene hypothesis and know-how the immune system recognize and neutralize foreign bacteria from harming the body
Learn about the hygiene hypothesis and understand how exposure to certain germs help develop a child's immunity
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allergy
allergy summary
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allergy: Facts & Related Content

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News •

Spring allergies are in bloom. Here's why and what to do about it : Short Wave • Apr. 15, 2025, 3:16 AM ET (NPR)
Doctor explains why allergy season started early this year • Mar. 26, 2025, 2:49 PM ET (CBS)
Allergy sufferers expected to have worse season than usual: See pollen maps • Mar. 22, 2025, 2:52 AM ET (USA Today)

Facts

Also Known As allergenic disease • hypersensitivity

Photos and Videos

allergy
anaphylaxis
skin test
What does hypoallergenic really mean for consumer products?
Why do people have allergies in the spring?
Learn about hygiene hypothesis and know-how the immune system recognize and neutralize foreign bacteria from harming the body
Learn about the hygiene hypothesis and understand how exposure to certain germs help develop a child's immunity
See All Videos and Images →

Related Topics and References

Topics
Dig Deeper: More Articles That Discuss This Topic

Key People

Charles Richet.
Charles Richet
French physiologist

Related Quizzes and Features

Quiz
Encyclopaedia Britannica thistle graphic to be used with a Mendel/Consumer quiz in place of a photograph.
44 Questions from Britannica’s Most Popular Health and Medicine Quizzes
List
Hand washing. Healthcare worker washing hands in hospital sink under running water. contagious diseases wash hands, handwashing hygiene, virus, human health
17 Questions About Health and Wellness Answered
Demystified
Macro Aedes aegypti Mosquito. Close up a Mosquito sucking human blood,
Why Do Mosquito Bites Itch?