Ringworm in Dogs: Causes, Symptoms & Treatment Guide

It may surprise many dog owners to learn that ringworm is not actually a worm. Instead, ringworm in dogs is a fungal infection affecting the skin, hair, and sometimes claws. This condition, medically known as dermatophytosis, is contagious and can spread between dogs, cats, and humans, making responsible management essential.

Understanding Ringworm: What Is It?

Ringworm results from fungi such as Microsporum canis, Microsporum gypseum, and Trichophyton mentagrophytes. These fungi invade the upper layers of the skin, hair follicles, and nails, causing circular patches of hair loss with scaly, red borders. Unlike internal worms, this fungal infection thrives on the skin's surface.

How Do Dogs Catch Ringworm?

Dogs become infected primarily through direct contact with infected animals or people. They can also catch it from contaminated environments—bedding, grooming tools, bowls, carpets, or soil harbouring fungal spores. These spores can remain viable for up to 18 months, making eradication challenging without thorough cleaning.

Recognising Ringworm in Dogs

The typical sign is a circular patch of hair loss with a raised, red, and scaly edge, often called a "ringworm lesion." These patches may appear on the face, ears, feet, tail, or nails. Infected nails may look dry, brittle, or cracked. Usually, ringworm isn’t painful but can cause itchiness, especially if secondary skin infections develop.

Treating Ringworm in Your Dog

If you suspect your dog has ringworm, it is important to seek a veterinary diagnosis. Ringworm can resemble other skin conditions like mange or dermatitis, so accurate diagnosis guides effective treatment. Treatment often involves:

• Topical antifungal creams or ointments for limited lesions
• Medicated antifungal shampoos to wash the coat thoroughly
• Clipping long or thick fur to aid medication penetration
• Systemic antifungal medication prescribed by your vet for widespread or persistent infections

Treatment courses typically last several weeks to ensure complete clearance and prevent reinfection. Do not use over-the-counter or human antifungals without veterinary advice, as these may be ineffective or harmful.

Preventing Spread and Protecting Your Family

Ringworm is zoonotic; it can pass between your dog and family members. To minimise risk:

• Wear gloves when handling infected pets and wash hands thoroughly after contact
• Wash and disinfect bedding, toys, bowls, and grooming tools regularly
• Vacuum carpets and clean floors often to remove fungal spores
• Prevent infected dogs from sleeping on beds or furniture during infection
• Avoid sharing towels, bedding, or clothing with infected animals

How Serious Is Ringworm?

Ringworm in dogs is generally not life-threatening but requires prompt treatment due to its contagious nature. Persistent infection can cause discomfort, secondary infections, and claw deformities, potentially affecting mobility. Young, elderly, or immunocompromised dogs may experience more severe cases. Moreover, the risk to humans, especially children, elderly, or immunosuppressed individuals, makes responsible treatment and hygiene vital.

Summary and Next Steps

Ringworm in dogs is a contagious fungal infection affecting skin, hair, and nails. Understanding its transmission, recognition, and treatment helps you protect your dog and family. Early veterinary diagnosis and diligent care support a full recovery. Maintain good hygiene and environmental cleaning to prevent spread. If you notice any suspicious skin areas on your dog, consult your vet without delay for appropriate diagnosis and treatment.