Ringworm, despite the name, is not a worm. It is a fungal skin disease that can infect dogs, cats, human beings, and a variety of other animals. Learn more about ringworm in dogs here.
Your dog may become exposed to many parasites in their environment with warmer weather. One of those parasites is the larva of the Cuterebra fly that may cause a wound or sore on your dog's skin.
Worms, or intestinal parasites, can affect all puppies and dogs. Intestinal parasitism is one of the most common conditions in clinical veterinary practice and is frequently identified in all dogs.