Ringworm on Dogs: Appearance

Despite its misleading name, ringworm is not caused by a worm. It is a common fungal infection, scientifically known as dermatophytosis, that affects the skin, hair follicles, and sometimes the nails of dogs (Source 1, 3, 5). This infection is prevalent globally and can affect nearly all domestic animal species, including dogs (Source 1).

Classic Appearance in Humans vs. Dogs

In humans, ringworm typically presents as a distinct, circular red rash with raised edges (Source 2). This classic "ring" appearance is what gives the infection its common name (Source 1). However, in dogs, the presentation can be more varied. While it can sometimes manifest as a classic ring, it often takes on other forms (Source 2).

Common Signs & Lesions

Recognizing the early signs of ringworm in dogs is crucial for effective treatment (Source 4, 5). The infection primarily affects the outermost layer of skin and hair follicles (Source 1).

Common signs and lesions to watch for include:

• Circular or irregularly shaped bald patches (alopecia): These are distinct areas where hair has fallen out (Source 4).
• Dandruff-like scales: These scales can be present within or around the bald patches (Source 2).
• Reddened or darkened skin: The affected skin may appear inflamed or discolored (Source 2, 5).
• Scabs or crusty areas: These can form on the lesions (Source 2).
• Inflamed skin: The skin may look irritated and red (Source 5).
• Dry, brittle hair: Hair in affected areas may become fragile and break easily (Source 5).
• Itchiness (pruritus): While not always present, some dogs may experience itching (Source 5).

Here is an example of what ringworm might look like on a dog's skin.