Well... I don't think your question if stupid at all.
I am basically allergic to the entire world around me... except for birds. However, I tend to prefer the self-imposed misery of surrounding myself with trees, flowers, grass, dust, cats. dogs, hay, horses, guinea pigs, etc.... If it makes me itch, it usually means it is alive and is something that I love! Sometimes short hairs dogs, even some Labradors, hair causes me to break out into a rash. ALSO- a rash can be your immune system's reaction to MULTIPLE STIMULI and you system becomes OVERWHELMED and 'wiggs out" - causing the rash. Go get yourself some benedryl... or go by Walgreen;s and ask the pharmacist for "WALFINATE." - It is a miracle antihistamine..... better than all the new stuff!!!!!!!!!!!!!!!!
My allergist says that the majority of humans are allergic to feathers... so you just might be in that majority. Just your luck, huh?
Or, you could be allergic to hay, or some other duck-related environmental factor.
Me - I am literally allergic to just about everything EXCEPT birds... so your rash, to me, sounds like to are allergic to the feathers or bedding (shavings, hay, etc.) Shavings especially produce a lot of dust into the air. Don;t worry - get yourself to a Walgreen's and buy some WALFINATE. YOU WILL LOVE IT!!!!!!!!!!!!!!! It's only a 4 hour pill, but it works WONDERS!!!!!!!!!!!!!!!! Plus, it has been around for ages, so it is very very safe to use.
As for preventing.. Make sure that your duck area is well ventilated for your health needs. Also, wear long sleeves/[ants, covering skin areas of contact. ALWAYS wash your hands AND FACE as soon as you enter your home. Try as best possible to to touch any parts of your body with your hands after you have come into contact with the ducks/duck area.
I LOVE, LOVE, LOVE the smell of my horses. I just think that horses have the BEST SMELL IN THE WORLD!!!!!! I love to wrap my arms around my big ole boy, Sydney, and kiss him, and snuggle. And as soon as I get inside, I have to wash my face, eyes, hands, neck, and arm, or I will break out into a rash. Just keep washing and washing and invest in a lot of allergy meds. ANIMALS ARE SOOOOOOOO WORTH ALL THE ALLERGIES IN THE WORLD!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!