Coccidia
 

My cat recently got treated for coccidia at the humane society. I brought him home and everything seemed fine. I also have a 4 week old puppy who just got dewormed. So I also started my cat on a preventative dewormer. But now I'm seeing Blood and mucus in my cat's stool again. I have no idea how to permanently get rid of this issue and I'm worried for my very young puppy. I need help to be able to completely get rid of this parasite...

You should call your vet back and let them know what is going with your kitty and try to keep your puppy away from the littler box. You don't want him trying to eat the kitty poop.

Coccidia can be a tough nut to get rid of--or at least, that's our experience with our dogs. A dewormer won't help with coccidia, since the organism responsible is a protozoan. If I'm remembering correctly, the drugs given to get rid of the organism just keep it in check until the animal's immune system can control it--and stress or illness or other things that stress the immune system, can cause a flare up. It sounds like your cat needs another round of treatment.

And, yes, keep puppy away from the litter box! Coccidia cysts are shed in the feces.