Both of my cats were strays, rescued from the animal shelter. They both came with it...they didnt have really bad cases. But i do know that my vet said it is hard to get rid of in cats, more so than in dogs. We just did the medicine thing and it eventually went away.

Make sure to clean the litter box often, so the cat cant re-infect himself. Even change the litter maybe once a week completely, as to get rid of all of the "germs" right away. And if you have other cats sharing in the same litter box...they could get it too...so change the litter very often or try to get him to go in another box. If he is an outdoor cat and uses the potty outside...then maybe he is re-infecting himself by being exposed to feces that has the coccidia in it outside...??

Sorry, i'm not much of help.

Anyway, welcome to Pettalk. You came to the right place...you will like it here

Robyn