The link below takes you to the cat fanciers site for Feline Infectious Peritonitis (FIP) a horrible, non-curable disease in cats.
If you have a few extra dollars, why not contribute towards research?
Another Feline Bordetella Site note, this can not be passed to humans however, which the article mentions. It is a slightly older article
when breeders and vets were just discovering cats could get Bordetella, and therefore, not all is correct in this website. It is a good website none the less.