Need advice on cat that was exposed to feline leukemia.

I need some advice. My room mate picked a stray up and after 4 months of the cat living with us was taken to get fixed but the cat came out positive for FeLV. My cat was negitive and had her FeLv shot done in november of last year. Is there still a percentage that a cat still can catch FeLv if they have shot? Also how long does it take for the virus to settle in(a cat to become positive?)? 2 other FeLv negitive cats came in contact with this cat and their shots were not up to date. We did not think anything was wrong with this cat for 4 months is it too late to prevent those 2 cats from getting it? Please any advice.

Asked by Member 957093 on Jun 25th 2010 in FIV (Feline Immunodeficiency Virus)