A fungal nail infection is a condition in which a fungus or yeast infects the nails.
A fungal nail infection is usually caused by a fungus called Trichophyton.
Fungal skin infections, such as athlete's foot, often lead to fungal nail infections. It is most common in adolescent and adult males and is rare in women and children under age 12. The fungus that causes the infection lives in warm, moist environments such as showers and locker rooms. A person is more likely to develop a fungal infection if he or she: