I have had allergies all my life,,, Severe, with a capital S, to most kinds of animal dander and to a lesser extent, fur. Dogs are strictly off limits to me, to the point of contact causing hives and swelling, asthma, eyes turning red and swelling, etc. Sometimes just being around people who own dogs and leave dog residue on their clothes causes me problems. When I did a lot of coyote hunting, I had to wear a mask, gloves, and goggles when handling them. A sneezing fit ain't nothin'....
Rabbit fur dubbing is strictly a no-go for my flies. Learned that early on. Thank God for the amount of synthetic materials we have today. I use that as another excuse, other than the weight of soaked fur, as to why I don't like rabbit strip flies. Actually the strips aren't too bad, but dubbing? Forget about it.
Stay away from allergy meds? Yeah right, I wish. When I was a kid, I started on the "desensitisation" road with a shots which were supposed to help, dam' near killed me. The meds have come a long way for offering relief without the side effects of the older - but very effective - stuff like benadryl.
To the simpleton, proof does not matter once emotion takes hold of an issue.