Why do we get immunity after being exposed to a pathogen but not an allergen?

Question

I get allergies almost everyday because of dust/pollen. But I will not get chickenpox after being exposed to it once.

In: 15

Answer 1

Because immunity to a virus like chickenpox is your immune system working as it’s supposed to, while an allergic reaction is basically your immune system malfunctioning and overreacting. In the case of dust or pollen, they aren’t attacking your body the way a virus does, so your body reacting to them is usually causing things to go wrong. When you develop immunity to a virus your body kinda saves the information on how to make those antibodies, so that it can react quicker next time. It can’t do that for common allergens, there’s no way for it to “learn” they are not harmful.