Why am I to avoid contact with pets?

I am 6 days post op from having silicone breast implants. My kids brought home a kitten. My aftercare packet provided by my ps says to avoid direct contact with pets, especially cats. I'm curious why this is. The kitten will not stay away from me and its pretty hard not to pet. Is the concern some sort of infection or possible trauma they could cause to the breast? If infection is the issue what can i do to counteract this?