I reckon you can only catch a virus if you believe in them. I've never caught one yet!:) I agree with you though. We eat, drink, breath and wear poisons yet attribute our poor health to invisible microbes.
No I wouldn't exile you. I'd just give you a 30 year supply of handkerchiefs. I have one about my person at all times.
I do try to keep a tissue in my pocket for unfortunate events, but now and then, about once every ten years or so, I am caught without.
Ok, exile for you then!