I never used anything but soap and warm water, and a tube of anitiobtic from the first aid kit.
First, I got rid of any excess hair, soaked area with soap and warm water, scrubbed the infected areas with my finger tips until scabs lifted off, and sores were free of pus. From then on, I just kept the area clean and dry as possible. I used little dabs of the anitibotic to cover infected area to keep moisture and dirt off. I never used any grooming items on him that I used on other horses. Went to the dollar store and got a few cheap brushes and just trashed them when I was done. Sounds time consuming, but it really isn't, maybe 10 or 15 minutes is all I spent each time.
I also had him in a smaller pasture away from the other horses.
Good luck.......