Allergies
Overview Allergies occur when your immune system reacts to a foreign substance — such as pollen, bee venom or pet dander — or a food that doesn’t cause a reaction…
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Overview Allergies occur when your immune system reacts to a foreign substance — such as pollen, bee venom or pet dander — or a food that doesn’t cause a reaction…
This is the VOA Special English Health Report. An allergy is an unusually strong reaction to a substance. Many things can cause allergies. The most common cause is pollen. Trees…