SRS - My cat has been spayed. Don't forget I got her at the SPCA.

If the other cats in the neighborhood are immunized, then they should be protected from disease.

As far as being a vector, last time I checked, she wasn't an arthropod. As far as being a carrier ??????? Who knows? If you are paranoid about my healthy, nature loving cat, keep your cat indoors.

Besides that, my cat is so mean, she won't let any other animal into her territory. I don't think you have anything to fear.