My poor little Jazz had it when we got her from the shelter. I had to keep her in a room quarantined for almost a month. She also had a URI but the ringworm was what lasted the longest. I had to put some kind of ointment on her and when that didn't improve my vet put her on medication that I had to give her orally once a day for four weeks. I found out later that the medicine has bad side effects and shouldn't have been given to her since she was a kitten.

Make sure you wash your hands good after touching each cat so you don't spread it to another or get it yourself. I kept hand santiizer in the room she was in plus Clorox wipes to open the door. I was also told to vacuum her room daily but I only did it weekly. I also disinfected the room she stayed in from top to bottom once she finally was allowed out in the house.

From things I've read about ringworm and multicat households, I think I was very lucky that no one else caugth it and it only lasted a month. Of course she probably had it for a while in the shelter.

Good luck.