I am so happy that it was not parvo. The diarrhea may last for a couple more days, so don't worry if it isn't resolved quickly. Keep her on a chicken/rice diet and very slowly reintroduce her normal dog food after her stools firm up and are no longer bloody.
AFAIK, coccidia isn't very contagious so your Yorkies should be in the clear
BIG hugs to you for getting this resolved and helping your pup on the road to recovery
