Are All Canine Ringworm Infections Contagious to Humans?

Ringworm becomes more serious if bacteria infect the skin lesions.
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Ringworm is a skin infection caused by dermatophytes, or fungi found in the soil and carried by pets into your home. Ringworm is highly contagious to humans and other pets exposed to dermatophytes. Children are the most susceptible humans, as they play on the floor where their canine companions roam. Humans can contract all canine ringworm infections. It is best to take your furry friend to your veterinarian for a diagnosis and treatments, and to disinfect his environment to protect your family.

Ringworm Symptoms

Ringworm lesions on humans are round, red, scaly rings. Since our canine friends generally are quite hairy, they appear on them as round patches of missing hair. It is most prominent on dogs on the head, ears, forelimbs and paws, with a crusty center on a bald patch of skin where the hair has fallen out. Pets most susceptible to ringworm are puppies under a year old and dogs with compromised immune systems and excessive stress. Cats and dogs can interchange ringworms between each other if they are in contact with the ringworm spores.

Veterinarian Diagnosis

If you notice any of the symptoms of ringworm on your dog, visit your veterinarian for confirmation of ringworm before it spreads to other pets or human family members. A vet may use a Wood's lamp, an ultraviolet light, to examine the hair, remove some hairs at the sight and examine them under a microscope, or take a skin scraping to examine it and make a diagnosis.

Ringworm Treatment

Treatment of ringworm usually involves a topical antifungal cream or lotion to apply to the infected areas. It cures the ringworm and relieves your pet from scratching the area, which would spread the fungus further. The vet may suggest an antifungal shampoo; some dogs with long hair may need shaving for the treatments to reach affected areas. Your dog's hair will grow back, often even thicker than before. Difficult, extreme cases of ringworm may warrant the use of oral antifungal drugs. Treatment of ringworm on humans is the same as for canine companions; it's best if treatment starts as soon as ringworm is discovered on humans, especially children, to prevent scratching the lesions and becoming infected, leading to a more serious condition.

Disinfection Practices

Along with veterinarian intervention and treatment of ringworm, you will need to sanitize your home. Sterilize all dog grooming brushes and combs in a solution of 1 part household bleach and 10 parts water to prevent spreading the spores. Vacuum all carpets and rugs, and clean all hard surfaces such as floor and countertops in the same dilution of bleach and water as for the grooming tools. Wash all bedding and pet clothing with bleach. The colors may lighten, but it's better than getting your entire family infected with ringworm.