Thank you everyone for your opions, it's very appreciated.

Well, first of all, I don't have a house of my own, only an appartment, so that way it is impossible for me keep a cat 100% isolated from Luna and Lily; it's just not possible. Also, I do not know anyone who lives without a cat and would adopt or foster one. And - I feel very bad to say that - I'm not in the financial position at the moment to pay another kitty's vet bills. Being both unemployed AND too sick to work, my situation is desperated enough anyway. I wish I'd have some money so that I could buy or rent a house and do fostering.

But I think what I can do is bringing some food and water for the kitty - just in case it's still there. I can also ask people (grave yard visitors) if the cat comes regulary or if it belongs to someone.

I think it's another good idea to always carry some of these disinfectant tissues with me, that way I don't have to fear to touch a cat and bring diseases home to my girls...

BTW, if you were not sure if a cat has a home or not, would you take it with you when it's obviously sick? After all, somebody might miss it...

Kirsten