Taking radioactive iodine?

I was just given a dose of Radioactive Iodine, but a very low does just used so I may have a scan done, not a treatment dose. My doctor told me to still follow the general precautions as normal, but my question is how secluded must I be? What kind of effect does this have on other people that is dangerous for them but okay for me? And also I have a 1 year old kitten who is dying for attention. Do I need to neglect her also or may she sit with me? Thanks.