Consider blister ringworm. Ringworm is a fungal infection, bacterial fungi can be latent for a long time.

Guidance:

Generally light in winter, heavy in spring, summer and fall, often wash your hands and feet, keep them dry and breathable. 9 ° - 12 ° vinegar essence, soak for half an hour before going to bed every night, soak and dry naturally, do not rinse with water; even soak for 10 to 15 days, will burst skin, burst after it, the bacteria are killed, the cells are also sacrificed.