What should you know about dog ringworm contagious?

Ringworm is caused by dermatophyte fungi, not a worm. Fungal material can pass between people and animals through skin contact or shared bedding, towels, clothing, grooming tools, and other surfaces. The rash may be circular, itchy, scaly, or more subtly irritated; its shape is not always a perfect ring. [Skin Rash](/symptoms/skin-rash/) and [Scaly Skin](/symptoms/skin-scaling/) can have many causes, so testing may be needed when the diagnosis is uncertain.

Avoid sharing towels, clothing, brushes, and bedding until treatment advice is given. Wash hands after touching an affected area or pet, keep skin clean and dry, and clean frequently handled surfaces. Do not share steroid cream or use a combination product without advice, because it can alter the appearance and allow fungus to persist. Depending on location and extent, a clinician may recommend [Topical Antifungal Treatment](/treatments/medical-dermatology/topical-antifungal-therapy/) or [Oral Antifungal Treatment](/treatments/medical-dermatology/oral-antifungal-therapy/).

Seek medical advice for a spreading rash, scalp involvement, broken skin, marked swelling, pus, fever, or symptoms in a child or someone with reduced immune defence. Arrange review if the rash is not improving as expected or returns after treatment. A household pet with hair loss or scaly patches should be assessed by a veterinarian so the source can be managed.

Ask whether the rash needs a scraping or culture, how long treatment should continue, which household items need cleaning, whether close contacts need assessment, and when it is reasonable to resume shared activities.