I know the virus can stay in their system for a long time, thankfully her brothers are only cats, so I really don't know. She got hit so severely at first, and her brothers were fine in a matter of days. I can't risk her being around other kitties as she's still shedding that virus from Hell. She's so affectionate, and loves to be held. She'll give me noserubs all day long if I had the time! I can only hope it won't crop up again!