Ringworm in dogs

Overview

Ringworm is a skin condition that is easily transmitted and highly contagious to other pets and humans. It's not actually a worm; ringworm is a fungus. Signs of infection can be difficult to detect there may be only a few broken hairs. Some dogs can carry the fungus and show no symptoms at all.

Symptoms

• Flaky bare patches, often circular, on the head, ears, paws, or tail, sometimes with a red outer rim due to inflammation
• Bumps or blister-like pimples
• Itching
• Hair loss

Cause & prevention

Dogs can get ringworm by contact with an infected animal or from fungal spores in the soil. An exposed dog does not necessarily become infected, but he can carry the disease to other dogs, cats and humans on his fur.

Dogs that have a weak immune system caused by poor nutrition, poor hygiene, illness, or living in situations in which a large number of animals are housed together have an increased risk for ringworm.

If one dog is diagnosed with ringworm, a vet should evaluate all pets in the household, and all bedding and brushes should be washed and disinfected. To prevent the infection from spreading from animal to animal, veterinarians recommend giving baths to all the pets in the household once a week for a number of weeks. Your vet can prescribe an anti-fungal shampoo, or may recommend an over-the-counter formula. Once you've lathered him up, let your dog sit about 5 minutes before rinsing. This will allow the anti-fungal action to take effect.

Wear gloves when handling an infected dog. Remember to wash your hands after you treat or touch your pet. Use a mild bleach solution, followed by plain soap and water.

The bare patches, with treatment, will clear up in one to three weeks, You may want to keep your infected pet separated from other animals in the household in the meantime. And finally, get out the vacuum cleaner! Ringworm can live on the hair that your pet sheds, so regular vacuuming will reduce the risk of recurrence. You will need to change the vacuum bag frequently.

Treatment

Ringworm may resolve itself and go away on its own after several months, but because it is so contagious, this is not a condition you should try to treat yourself. Your veterinarian may examine affected hair under a microscope, use an ultraviolet light or perform a culture to diagnose infection. If your dog has been diagnosed with ringworm, you will need to keep the infected patches clean. Some veterinarians recommend washing the area with an antiseptic soap that contains povidone iodine or chlorhexidine. You should also apply an anti-fungal cream twice a day.

If topical treatment proves unsuccessful, your pet's doctor may prescribe a strong oral medication that will kill the fungus. Your dog should have a blood test performed before oral anti-fungal medications are started due to risks of liver damage with these drugs.  Dogs that don't respond well to treatment should see a veterinary dermatologist.

If you have a long-haired dog, it's a good idea to trim the fur around the flaky patches. An electric trimmer works best. This will make the area easier to treat and will help stop the fungus from gaining more ground.  You may feel more comfortable having a grooming professional clip your dog's hair.  Make sure you tell your groomer that your dog has ringworm so they can protect themselves and dispose of the hair appropriately. 

Resources:

VetCentric.com. Canine and Feline Ringworm.