Cara had coccidia when we got her, but I have read research that it is killed more easily with ammonia than bleach so that's what I used–- pick up, pour ammonia over area. Neither Connor nor Arwen got it. But since you weren't doing it before, do take in stool samples of the other dogs to avoid them continuing to pass it around. A dog can have it with limited effect and still be passing it in stools to recontaminate your pup.
http://www.sheltermedicine.vet.cornell.edu//shelter/coccidia.htm