Long as rash lasts. Ringworm is a fungus infection. It is common and spreads fairly easily. It is contagious for as long as you have the rash on your skin.
Ringworm. Ringworm is a highly contagious fungal infection that lives off of a host and that passes from person to person either through direct contact, through contact with an infected object, or through contact with an infected pet or infected soil. It may take few weeks before it completely resolves with treatment.
Until treated. This superficial dermatitis is produced by a fungus which will remain present and communicable until treated and cured.
A day or two.... ..After starting a good topical antifungal agent, there is little if any chance of spreading the infection to others - assuming, of course, that the antifungal cream is being applied diligently, twice a day.
How long is someone with ringworm contagious for? (# days prior and after skin rash symptoms) What need to do to prevent transfer to others
Good hygiene. And use of antifungal creams will keep you from being contagious I think 2 to 3 days of twice daily applications of cream will get you "non contagious" but continue treatment for 7 to 10 days.