TED ED VID: Why do some people have seasonal allergies?

[Ryan Goble]

Why do some people have seasonal allergies? Animation by Lisa LaBracio Ah, spring. Grass growing, flowers blooming, trees budding. For those with allergies, though, this explosion of new life probably inspires more dread than joy. So what’s behind this annual onslaught of mucus? Eleanor Nelsen explains what happens when your immune system goes rogue. View full lesson »