Question: Why are some people allergict to certain animals and not others?

Kevin Mahon answered on 11 Jun 2012:

In a nutshell, animals secrete proteins (from their sweat, saliva, urine and even their hair) that cause certain people to react badly to them.

They react badly because their immune system thinks these harmless proteins are in fact dangerous. This is down to genetics – chances are if you’re allergic to a cat/dog your mum or dad are too.!