Oh those bunny pics, I love them so......as much as Yorkies
Yes, it is the saliva that folks are allergic to. Does he know if he is allergic to rabbits? Rabbits clean themselves like cats and distribute the saliva over their hair,fur,wool. I would suggest going to a craft store where you can still find a rabbit hide or two =:0 but I guess the saliva would be gone off of those or fur collars on coats..... OH, a pet store, if you have bunnies at the local pet store, ya'll could visit and proceed from there.....?
Our cat brought us a wild baby bunny once and I kept it in a bucket in the laundry room. It had ticks! So out he/she went! Fleas jump pretty high, they can reach a rabbit in an outside hutch and if they can hang on to the nose area or hiney area or the eyes, they can do what they need to do! Cats can have silky hair too!