Feline Parvo-how contagious is it?

my FIL's cat & all her kittens just died of Parvo. I was around all them just before they got sick. could i have brought the virus home to my kitties?? i know there's a couple feline diseases that people can bring home on their clothes, but i can't remember which ones. i'm worried, could my kitties catch it? how would i know if they did or if they're in the clear?