The nail gradually thickens, and becomes discoloured and brittle. Caseous-looking material forms beneath the nail, or the nail becomes chalky and disintegrates. M.canis is usually contracted from infected kittens or puppies. The highly contagious Microsporum audouinii , which spreads from person to person, does not occur in Australia. Tinea capitis may extend to tinea corporis.
Occurrence is worldwide.
Males are infected more than females. Infection can occur from direct or indirect contact with skin and scalp lesions of infected persons or animals. The infectious agents are Microsporum trichophyton and Epidermophyton floccosum . Infection is more frequent and severe in hot weather. The infectious agents are Trichophyton rubrum , T. mentagrophytes var. interdigitale, Epidermophyton floccosum .