allergy

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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

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allergy

allergy summary

allergy: Facts & Related Content

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Last Updated: Dec 09, 2025

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Early RSV infection turns maternal allergy into a powerful driver of childhood asthma • Dec. 8, 2025, 3:10 PM ET (News-Medical)

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Also Known As	allergenic disease • hypersensitivity

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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

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Topics

food allergy type II hypersensitivity photosensitivity type III hypersensitivity type IV hypersensitivity MSG symptom complex pigeon fancier’s lung malt worker’s lung humidifier fever What Causes Allergies?infectious disease foodborne illness motion sickness necrosis blister cardiovascular disease mental disorder nervous system disease digestive system disease nutritional disease

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Key People

Charles Richet.

Charles Richet

French physiologist

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