Ringworm is a fungal infection that is somewhat contagious, but not very contagious, and the likelihood of mutual transmission from occasional household contact is low. Both mycelium and spores of the fungus are somewhat contagious, but the contagiousness is weak, and it tends to occur in dark, damp, and airless areas, such as the groin and perineum, and is closely related to the host’s own resistance. Generally, people who are healthy and have strong resistance and have good hygiene habits will not be infected, but the elderly, or people with diabetes, immune diseases such as lupus, dermatomyositis, and other long-term applications of hormones, or People with long-term application of immunosuppressants after organ transplantation should be on high alert. In addition to direct contact, shared use of household items is a common route of transmission, as sporulating bacteria are resistant to adverse environments and can survive for months in general environments, except for high-pressure steam sterilization. For patients with ringworm, care should be taken not to share clothing, shoes and socks, bath tubs, etc. with others, and underwear should be loose and breathable, and cotton is preferred. Avoid mutual infection. If ringworm is combined with tinea capitis, you should actively treat it to avoid spreading it to yourself. Because the pathogen of ringworm can survive in the environment for a long time, the treatment of ringworm must be long-term, thorough and according to the course of treatment. In addition to extending the course of topical medication appropriately (usually 2 weeks after the symptoms have disappeared), it is also important to pay attention to the disinfection of intimate products.