Red, circular skin lesions: this tell-tale sign of ringworm is unmistakable, whether it appears on you or your dog. But despite its name, ringworm in dogs isn't always a round lesion or a worm— it's a common skin infection that's highly contagious.

In cases of dog ringworm, these lesions typically appear on the face, ears, tail or feet. While these infected areas are pretty easy to spot, ringworm can also spread to other, more hidden, areas of your pet's body, which can make its transmission all too easy.

The good news is that while dog ringworm is pesky, it's also highly preventable and fairly easy to treat.

How Is Ringworm in Dogs Spread?

Dogs often acquire ringworm — or dermatophytosis, as your veterinarian might refer to it — from digging. It's relatively easy to treat and doesn't cause severe disease. However, ringworm in dogs can be difficult to manage, due to the fact that it's highly contagious and can be transmitted via fomites.

A fomite is any object or material that can carry an infection. In short, anything your pet touches can harbor and transmit ringworm to other dogs, cats or people. Any brushes, bedding, food, water bowls or toys — anything your dog comes in contact with — should be disinfected if ringworm enters the picture.

Additionally, any infected dog is considered highly contagious to other animals and humans. Wear gloves or wash your hands and clothes after handling your pet, and keep them quarantined until your vet declares that they're free of infection.

Does Ringworm in Dogs Affect All Breeds?

Not all dogs that come in contact with ringworm will show signs of an infection. Ringworm infections depend on the type of fungus, as well as the dog's age, relative health, nutrition and grooming.

Any dog can develop a ringworm infection, however, certain age ranges and breeds are more at risk. In an article for DVM360, veterinary dermatologist Anthea Schick says Boston terriers, Yorkies and Jack Russell terriers are all prone to contracting ringworm. Very old dogs, puppies and dogs who have a suppressed immune system, she continues, are at an increased risk for developing ringworm.

Dogs with ringworm are contagious to humans. If your dog has been diagnosed, or if you suspect they may have ringworm, do not handle them and then directly touch your skin. Wash your hands after every touch, and if you notice any red, circular itchy spots on your own skin, call your doctor.

How Is Dog Ringworm Diagnosed and Treated?

Your vet will usually diagnose ringworm via physical examination and one or more simple lab tests. The Wood's Lamp, fungal culture and direct examination of hairs under a microscope are the most common ways of diagnosing ringworm. Occasionally, ringworm in dogs is diagnosed via skin biopsy or polymerase chain reaction (PCR) from samples sent to a reference lab.

Ringworm is treated with antifungal medication, either topical, oral or a combination of both. There are several lotions, creams and shampoos available by prescription from your vet as well. Ringworm can also be treated with prescription-only oral antifungal medication.

Dogs are often shaved in the area of infection to help prevent the spread of disease through contaminated hair. In some cases, ringworm infections can return; however, treatment in these dogs can still speed healing and reduce the likelihood of the disease being transmitted to other animals or humans.

Beagle lays on carpet while woman vacuums.

How to Decontaminate Your Home After a Ringworm Diagnosis

Remember, ringworm loves to travel and infect new hosts via fomites, which is why a key part of treating it is to disinfect your home. If your dog has ringworm, vets recommend:

  • Confining them to a single area that can be cleaned easily. If that area is carpeted, vacuum it once a day.
  • Using diluted bleach (1:10 mixture in water) or an all-purpose cleaner to clean all nonporous surfaces twice a week (i.e. counters, tabletops, etc.).
  • Wiping all floors and walls with dry cloths once a week.
  • Washing all pet bedding on the hottest setting weekly, and throwing away any bedding or toys that are hard to clean.
  • Changing your clothes immediately after handling them, and putting potentially infected clothing in the washer as soon as possible.

In severe cases in which you have children at home or more than one pup, you may also want to clean your home's air ducts and replace any air filters.

Is Ringworm in Dogs Preventable?

One way to prevent ringworm is to not let your dog dig in rodent holes, as this is how infection often occurs. The likelihood of a ringworm infection can also be reduced by making sure your dog is in otherwise good health.

If you take your dog in once or twice a year for vet wellness visits, follow all their recommendations and practice preventative nutrition by feeding them a complete and balanced diet, you'll be well on your way to keeping ringworm away.

Dr. Sarah Wooten Dr. Sarah Wooten

Dr. Sarah Wooten graduated from UC Davis School of Veterinary Medicine in 2002. A member of the American Society of Veterinary Journalists, Dr. Wooten divides her professional time between small animal practice in Greeley, Colorado, public speaking on associate issues, leadership, and client communication, and writing. She enjoys camping with her family, skiing, SCUBA, and participating in triathlons.

Related articles

How Long Are Dogs Pregnant?

Learn about the pregnancy cycle in dogs, including how long they are usually pregnant and details about each trimester.

How to Find an Amazing Vet for Dogs You Love

Choosing a veterinarian for your dog is extremely important to your dog's health. Consider these things when choosing a vet for your canine friend.

Pyloric Stenosis in Dogs: Causes, Symptoms, & Treatment

Learn details about pyloric stenosis in dogs, including how serious of a health concern it is, common signs, how it's diagnosed and treatment options.

Safety Tips for Walking Dogs at Night

Learn helpful safety tips for walking your dog at night, including how to stay visible and special considerations to keep in mind when walking after dark.

Important Information About Spaying & Neutering Your Puppy

Learn about the benefits to spaying or neutering your puppy, including questions about the surgery and what to expect after he's done.

Strokes in Dogs: Signs, Risk Factors & What You Should Do

Strokes in Dogs: Signs, Risk Factors & What You Should Do

Dog Park Rules: Do's and Don'ts

Learn about the dog park rules that make for a fun time at the park. Park outings are a fun way to socialize with your dog, but safety comes first.

Why Does My Dog Eat So Fast?

It's common for dogs to eat faster than humans, but learn why exactly some dogs might eat too fast and any health issues that can come up because of it.

How to Spot & Treat Dog Bug Bites

Dog bitten by pesky insect? Learn how to identify common bug bites on your dog, including ticks, mites, fleas & mosquitoes, and how they can be treated.

Facial Paralysis in Dogs: Is Your Pup Looking Droopy?

Learn how to recognize the signs of facial paralysis in dogs, understand its causes and how the condition can be managed with the help of your vet.

How to Celebrate Your Dog's Birthday in Style

Thinking about hosting a dog birthday party? Read on to discover how to celebrate your dog's birthday with festivities that'll be the talk of the dog park.

Best Dog Breeds for Hot Weather

If you live in a warm area and are thinking of adopting a dog, you might be wondering "what are the best dog breeds for hot weather?"

Gastrointestinal & Digestive Disorders in Dogs: Types & Causes

Learn about the warning signs, symptoms, and treatments of Gastrointestinal (GI) disorders and diseases that affect a dog.

Treating Your Dog with and without Food

Learn how to treat your dog without compromising its health. Get tips on how to spoil your pup without too much snacking on dog treats.

Why Fiber is Important for Your Dog's Health

Learn why fiber is an important part of a dog's diet, including the best sources of fiber, why solubility is key, how fiber can help manage disease & more.

What Causes a Heart Murmur in Dogs?

Concerned about a heart murmur in dogs? Learn more about what might be causing it and what you can do to help your dog.

Learn About the Best Dog Breeds for Children

Learn tips for choosing the best dog breed for your children and family, considering things like breed size, energy level, temperament and age.

Treating a Torn ACL/CCL in Dogs: TPLO Surgery & More

Learn about torn CCL injuries in dogs (equivalent to a torn ACL in humans), including risk factors, how they are diagnosed and how TPLO surgery can help.

Does My Dog Need A Winter Coat?

You pile on layers when it's cold out, but do dogs need winter coats, too? Learn how breed size & your dog's age can help you decide if it's a good idea.

Reducing Holiday Party Stress for Your Dog

Learn the best way to keep your dog comfortable & stress-free during a holiday party, including introducing him to guests & giving him a quiet place to res