Ringworm in Dogs: Symptoms, Treatment & Is It Contagious?

Ringworm, despite its name, isn’t caused by a worm. It’s a fungal infection that affects the skin, hair, and nails of dogs, as well as other animals and humans. Understanding ringworm is crucial for pet owners to ensure proper diagnosis, treatment, and prevention of its spread.

Symptoms of Ringworm in Dogs

The clinical signs of ringworm can vary greatly from dog to dog. Some dogs may show no symptoms at all, acting as carriers of the fungus. Common symptoms include:

• Circular lesions: The classic sign is a circular patch of hair loss, often with redness and scaling around the edges. These lesions aren’t always perfectly circular, and they can be itchy, though not always intensely so.
• Hair loss: Patches of hair loss, often patchy and irregular, are frequently seen. The hair may appear broken off near the skin.
• Scaling and crusting: The affected skin may be dry, flaky, and scaly. Crusts may also form on the lesions.
• Inflammation: The skin may be red, swollen, and inflamed.
• Nail infections (onychomycosis): In some cases, ringworm can infect the nails, causing them to become brittle, deformed, and discolored.
• Puppies are more susceptible: Younger dogs, particularly puppies, are more likely to develop ringworm infections, as their immune systems are still developing.

Diagnosing Ringworm

Diagnosing ringworm requires a visit to the veterinarian. Several diagnostic methods can be used:

• Wood’s lamp examination: A Wood’s lamp emits ultraviolet light. Some species of ringworm fungi will fluoresce (glow) under this light, but not all. A negative result doesn’t rule out ringworm.
• Microscopic examination of hair and skin: The veterinarian may pluck hairs and scrape skin cells from the affected area and examine them under a microscope to identify fungal spores.
• Fungal culture: This is the most accurate method. A sample of hair and skin is placed on a special culture medium, and if ringworm is present, the fungus will grow. This process can take several days to a few weeks.

Treatment Options

Treatment for ringworm depends on the severity of the infection and the number of lesions. Common treatments include:

• Topical antifungal medications: Antifungal creams, ointments, or shampoos are often used to treat localized infections. The affected area should be clipped of hair before applying the medication.
• Oral antifungal medications: For more severe or widespread infections, oral antifungal medications may be prescribed. These medications can have potential side effects, so regular monitoring by a veterinarian is necessary.
• Lime sulfur dips: These dips involve bathing the dog in a diluted lime sulfur solution. They are effective but can have a strong odor and stain light-colored fur.
• Environmental decontamination: Ringworm spores can survive in the environment for a long time. Thorough cleaning and disinfection of the dog’s environment (bedding, toys, carpets, etc.) is crucial to prevent reinfection. Bleach solutions (diluted appropriately), antifungal sprays, or steam cleaning can be used.

Is Ringworm Contagious?

Yes, ringworm is highly contagious. It can spread to other animals, including cats, and to humans. Transmission occurs through direct contact with an infected animal or contaminated objects (e.g., bedding, grooming tools). Children and individuals with weakened immune systems are particularly susceptible. It is important to:

• Wear gloves when handling an infected dog.
• Wash your hands thoroughly after contact.
• Disinfect surfaces and objects that the dog has come into contact with.
• Isolate the infected dog from other pets and people until cleared by a veterinarian.

With prompt diagnosis and appropriate treatment, ringworm infections in dogs can be successfully managed. Consulting with your veterinarian is essential for developing the best treatment plan for your pet and preventing the spread of the infection.