What are vampires alergic to?

Answer 1

Generally it depends on what world of fiction you're asking. However traditionally, they are extremely sensitive to UV rays which causes them to burn to a crisp very easily. This came from the idea that, long ago, people who were thought to be vampires had stayed inside and refused to be exposed to sunlight, however they may have actually suffered an advanced form of photosensitivity.
There is also the idea that vampires are allergic to garlic, however this can be contradicted by the idea that vampires are extremely sensitive to the smell and despise it.
Hope that helps.