Ambah - me too. I've had cats in my bed every night since I was about 3! And have also cleaned up some pretty good messes.....
My dr said I could wear gloves and still change the litter trays if I wanted too - I didn't so I never told Shane that bit, and he changed them all through my last pregnancy.
You just have to make sure you wash your hands, as an immunity doesn't mean you still wont get it if you come into contact. Just means you have less liklehood - if that makes sense?