While you can kill the fungus that causes ringworm on your dog with a combination of topical and oral medications, the spores of the fungus are quite durable. They survive in the environment for months and are difficult to eradicate. It is difficult to remove all traces of the fungus from places that house numerous dogs, such as kennels. In addition to cleaning all surfaces that may be contaminated, the American Society for the Prevention of Cruelty to Animals recommends using a bleach solution to disinfect everything possible.
Clean, Then Disinfect
It is important to discard all disposable items, launder all fabric items in hot water and clean all of the floors, walls and cage surfaces before attempting to disinfect the kennel. Wash all food and water dishes in a commercial dishwasher if available and allow them to dry thoroughly before replacing them. Use a mop to clean the floors and vacuum carpeted areas regularly as dog hair often carries spores. Unfortunately, many common veterinary disinfectants, such as quaternary ammonium compounds, are ineffective against ringworm. However, a bleach solution made from a half cup of bleach in 1 gallon of water is effective to kill the fungus and the spores. Always be sure to wash your hands frequently when dealing with ringworm-infested dogs and kennels, as humans can contract the fungus as well. Be sure to use hot water and plenty of anti-bacterial soap when washing your hands.